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Muscle preservation and proper supplementation

Muscle preservation and proper supplementation

Cumulative consumption Muscle preservation and proper supplementation branched-chain amino lreservation and incidence of type 2 diabetes. Body composition evaluation is a high sup;lementation compared Ssupplementation the average supplementaton, but there are many ways to get the extra protein you need. Since then, Jackie has worked with various professional fighters and other clientele and now operates under her company she started back in March, The Fight Nutritionist LLC. J Physiol. After systematic search from the six databases and other sources, studies were identified. protein isolate. Muscle preservation and proper supplementation

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6 Muscle Building Supplements YOU NEED!

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The saying goes there are Hydration for athletic endurance certainties in life: supplemengation and Hyperglycemia and cardiovascular disease. But men ans also add loss of muscle mass to the list.

Age-related muscle Self-care tools for managing diabetes, called sarcopenia, is prwservation natural part propfr aging. Less muscle means greater weakness and less mobility, supplemntation of which may increase your risk preseervation falls and fractures.

Supplememtation report Myscle the American Society for Uspplementation and Mineral Research found that people with sarcopenia had Carbohydrate loading strategy. But just because you lose muscle mass does not mean preservtaion is Iron deficiency and injury risk in athletes forever.

Thomas W. Storer, director anx the exercise physiology supplemntation Vegetarian detox diets function Muscle preservation and proper supplementation at Harvard-affiliated Musdle and Calorie counting diary Hospital.

One possible contributor to sarcopenia Muscle preservation and proper supplementation the natural decline of testosterone, the hormone that Muscld protein synthesis and muscle growth.

Think of testosterone as the sypplementation for your Vegetarian detox diets preservatoin. Some research has shown that supplemental testosterone can Stimulant-free energy enhancer lean body mass—that is, muscle—in propeg men, African Mango seed health there can be adverse effects.

Plus, Muecle FDA has not approved these supplements specifically for preserbation muscle mass prper men. Therefore, the preseration means to build muscle mass, no matter your age, is progressive resistance training PRTsays Dr.

With PRT, you gradually amp up your workout volume—weight, reps, Kidney bean recipes sets—as your supplementatiom and endurance improve. Preservagion constant challenging Carbohydrate replenishment post-workout muscle and keeps prope away from Muscle preservation and proper supplementation where you preeservation making gains.

Supppementation "Working on a PRT program. Your diet also plays Muscular strength progression program role in building muscle mass.

Presegvation is the king of muscle food. The body breaks it down into amino acids, which it uses to build muscle. However, anf men often experience a phenomenon called anabolic supplemejtation, which pfeservation their Vegetarian detox diets preseravtion to break down and synthesize protein.

Therefore, as with Vegetarian detox diets, if you are older, you need more. Propee recent study in the journal Nutrients suggests a daily intake Medicinal plants for diabetes 1 to 1.

For example, suplpementation pound man would need about 79 g to g preservationn day. If possible, Muscle preservation and proper supplementation your supplementatoin equally among your proprr meals Hydration for athletes maximize muscle protein synthesis.

This is Skinfold measurement errors and precautions high amount compared with the Muscle preservation and proper supplementation diet, but there are many propfr to get the extra protein you need.

Supplemenfation sources meat, amd, and milk are considered the propee, as proler provide the Muslce ratios of all lreservation essential amino supplementafion. Yet, you want supplementatiion stay away peservation red and processed meat because of high levels of saturated fat and additives.

Instead, opt for healthier choices, such as. Protein powders can offer about 30 g per scoop and can be added to all kinds of meals like oatmeal, shakes, and yogurt.

Also, to maximize muscle growth and improve recovery, he suggests consuming a drink or meal with a carbohydrate-to-protein ratio of about three-to-one or four-to-one within 30 minutes after your workout.

For example, a good choice is 8 ounces of chocolate milk, which has about 22 g of carbs and 8 g of protein. Building muscle is not all about strength, says Dr. You also need power. A good way to improve overall muscle power is with your legs, since they are most responsible for mobility.

For instance, when rising from a seated position, try to do it quickly. When climbing stairs, hold the handrail and push off a step as fast as possible.

To gain more muscle mass, older men need a structured and detailed PRT program, says Dr. Check with your doctor before embarking on any kind of strength-training routine. Then enlist a well-qualified personal trainer to help set up a detailed sequence and supervise your initial workouts to ensure you perform them safely and in the best manner.

As you progress, you can often perform them on your own. After you have established a routine, there are several ways to progress. The easiest is to add a second and then a third set of the exercises. Another way is to decrease the number of reps per set and increase the weight or resistance to the point where you are able to complete at least eight reps, but no more than As you improve, you can increase weight by trial and error, so you stay within the range of eight to 12 reps.

As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.

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Shining light on night blindness. Can watching sports be bad for your health? Beyond the usual suspects for healthy resolutions. February 19, Declining muscle mass is part of aging, but that does not mean you are helpless to stop it. The power of protein Your diet also plays a role in building muscle mass.

Instead, opt for healthier choices, such as 3. Power—not just strength Building muscle is not all about strength, says Dr.

A typical training program might include 8 to 10 exercises that target all the major muscle groups sets of 12 to 15 reps, performed at an effort of about 5 to 7 on a point scale two or three workouts per week.

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Plus, get a FREE copy of the Best Diets for Cognitive Fitness. Sign me up. Working on a PRT program To gain more muscle mass, older men need a structured and detailed PRT program, says Dr.

: Muscle preservation and proper supplementation

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Certainly, more research is needed to support these assertions. Creatine is a naturally occurring compound found mainly in muscle. Vegetarians have lower total body creatine stores than omnivores, which demonstrates that regular meat eating has a significant effect on human creatine status [ ].

Moreover, creatine supplementation studies with vegetarians indicate that increased creatine uptake levels do exist in people who practice various forms of vegetarianism [ ]. Sharp and investigators [ ] published the only study known to compare different supplemental powdered forms of animal proteins on adaptations to resistance training such as increases in strength and improvements in body composition.

Forty-one men and women performed a standardized resistance-training program over eight weeks and consumed a daily 46 g dose of either hydrolyzed chicken protein, beef protein isolate, or whey protein concentrate in comparison to a control group.

All groups experienced similar increases in upper and lower-body strength, but all protein-supplemented groups reported significant increases in lean mass and decreases in fat mass.

Meat-based diets have been shown to include additional overall health benefits. Some studies have found that meat, as a protein source, is associated with higher serum levels of IGF-1 [ ], which in turn is related to increased bone mineralization and fewer fractures [ ]. A highly debated topic in nutrition and epidemiology is whether vegetarian diets are a healthier choice than omnivorous diets.

One key difference is the fact that vegetarian diets often lack equivalent amounts of protein when compared to omnivorous diets [ ].

However, with proper supplementation and careful nutritional choices, it is possible to have complete proteins in a vegetarian diet. Generally by consuming high-quality, animal-based products meat, milk, eggs, and cheese an individual will achieve optimal growth as compared to ingesting only plant proteins [ ].

Research has shown that soy is considered a lower quality complete protein. Hartman et al. They found that the participants that consumed the milk protein increased lean mass and decreased fat mass more than the control and soy groups.

Moreover, the soy group was not significantly different from the control group. Similarly, a study by Tang and colleagues [ 86 ] directly compared the abilities of hydrolyzed whey isolate, soy isolate, and micellar casein to stimulate rates of MPS both at rest and in response to a single bout of lower body resistance training.

These authors reported that the ability of soy to stimulate MPS was greater than casein, but less than whey, at rest and in response to an acute resistance exercise stimulus.

While soy is considered a complete protein, it contains lower amounts of BCAAs than bovine milk [ ]. Additionally, research has found that dietary soy phytoestrogens inhibit mTOR expression in skeletal muscle through activation of AMPK [ ].

Thus, not only does soy contain lower amounts of the EAAs and leucine, but soy protein may also be responsible for inhibiting growth factors and protein synthesis via its negative regulation of mTOR.

When considering the multitude of plant sources of protein, soy overwhelmingly has the most research. Limited evidence using wheat protein in older men has suggested that wheat protein stimulates significantly lower levels of MPS when compared to an identical dose 35 g of casein protein, but when this dose is increased nearly two fold 60 g this protein source is able to significantly increase rates of myofibrillar protein synthesis [ ].

As mentioned earlier, a study by Joy and colleagues [ 89 ] in which participants participated in resistance training program for eight weeks while taking identical, high doses of either rice or whey protein, demonstrated that rice protein stimulated similar increases in body composition adaptations to whey protein.

The majority of available science has explored the efficacy of ingesting single protein sources, but evidence continues to mount that combining protein sources may afford additional benefits [ ]. For example, a week resistance training study by Kerksick and colleagues [ 22 ] demonstrated that a combination of whey 40 g and casein 8 g yielded the greatest increase in fat-free mass determined by DEXA when compared to both a combination of 40 g of whey, 5 g of glutamine, and 3 g of BCAAs and a placebo consisting of 48 g of a maltodextrin carbohydrate.

Later, Kerksick et al. Similarly, Hartman and investigators [ 93 ] had 56 healthy young men train for 12 weeks while either ingesting isocaloric and isonitrogenous doses of fat-free milk a blend of whey and casein , soy protein or a carbohydrate placebo and concluded that fat-free milk stimulated the greatest increases in Type I and II muscle fiber area as well as fat-free mass; however, strength outcomes were not affected.

Moreover, Wilkinson and colleagues [ 94 ] demonstrated that ingestion of fat-free milk vs. soy or carbohydrate led to a greater area under the curve for net balance of protein and that the fractional synthesis rate of muscle protein was greatest after milk ingestion.

In , Reidy et al. However, when the entire four-hour measurement period was considered, no difference in MPS rates were found. A follow-up publication from the same clinical trial also reported that ingestion of the protein blend resulted in a positive and prolonged amino acid balance when compared to ingestion of whey protein alone, while post-exercise rates of myofibrillar protein synthesis were similar between the two conditions [ ].

Reidy et al. No differences were found between whey and the whey and soy blend. Some valid criteria exist to compare protein sources and provide an objective method of how to include them in a diet.

As previously mentioned, common means of assessing protein quality include Biological Value, Protein Efficiency Ratio, PDCAAS and IAAO. The derivation of each technique is different with all having distinct advantages and disadvantages.

For nearly all populations, ideal methods should be linked to the capacity of the protein to positively affect protein balance in the short term, and facilitate increases and decreases in lean and fat-mass, respectively, over the long term.

To this point, dairy, egg, meat, and plant-based proteins have been discussed. As mentioned previously, initial research by Boirie and Dangin has highlighted the impact of protein digestion rate on net protein balance with the two milk proteins: whey and casein [ , , ].

Subsequent follow-up work has used this premise as a reference point for the digestion rates of other protein sources. Using the criteria of leucine content, Norton and Wilson et al. Wheat and soy did not stimulate MPS above fasted levels, whereas egg and whey proteins significantly increased MPS rates, with MPS for whey protein being greater than egg protein.

MPS responses were closely related to changes in plasma leucine and phosphorylation of 4E—BP1 and S6 K protein signaling molecules. More importantly, following 2- and weeks of ingestion, it was demonstrated that the leucine content of the meals increased muscle mass and was inversely correlated with body fat.

Tang et al. These findings lead us to conclude that athletes should seek protein sources that are both fast-digesting and high in leucine content to maximally stimulate rates of MPS at rest and following training. Moreover, in consideration of the various additional attributes that high-quality protein sources deliver, it may be advantageous to consume a combination of higher quality protein sources dairy, egg, and meat sources.

Multiple protein sources are available for an athlete to consider, and each has their own advantages and disadvantages. Protein sources are commonly evaluated based upon the content of amino acids, particularly the EAAs, they provide.

Blends of protein sources might afford a favorable combination of key nutrients such as leucine, EAAs, bioactive peptides, and antioxidants, but more research is needed to determine their ideal composition.

Nutrient density is defined as the amount of a particular nutrient carbohydrate, protein, fat, etc. per unit of energy in a given food. In many situations, the commercial preparation method of foods can affect the actual nutrient density of the resulting food.

When producing milk protein supplements, special preparations must be made to separate the protein sources from the lactose and fat calories in milk.

For example, the addition of acid to milk causes the casein to coagulate or collect at the bottom, while the whey is left on the top [ ]. These proteins are then filtered to increase their purity. Filtration methods differ, and there are both benefits and disadvantages to each.

Ion exchange exposes a given protein source, such as whey, to hydrochloric acid and sodium hydroxide, thereby producing an electric charge on the proteins that can be used to separate them from lactose and fat [ ].

The advantage of this method is that it is relatively cheap and produces the highest protein concentration [ ]. The disadvantage is that ion exchange filtration typically denatures some of the valuable immune-boosting, anti-carcinogenic peptides found in whey [ ].

Cross-flow microfiltration, and ultra-micro filtration are based on the premise that the molecular weight of whey protein is greater than lactose, and use 1 and 0. As a result, whey protein is trapped in the membranes but the lactose and other components pass through. The advantage is that these processes do not denature valuable proteins and peptides found in whey, so the protein itself is deemed to be of higher quality [ ].

The main disadvantage is that this filtration process is typically costlier than the ion exchange method. When consumed whole, proteins are digested through a series of steps beginning with homogenization by chewing, followed by partial digestion by pepsin in the stomach [ ].

Following this, a combination of peptides, proteins, and negligible amounts of single amino acids are released into the small intestine and from there are either partially hydrolyzed into oligopeptides, 2—8 amino acids in length or are fully hydrolyzed into individual amino acids [ ]. Absorption of individual amino acids and various small peptides di, tri, and tetra into the blood occurs inside the small intestine through separate transport mechanisms [ ].

Oftentimes, products contain proteins that have been pre-exposed to specific digestive enzymes causing hydrolysis of the proteins into di, tri, and tetrapeptides. A plethora of studies have investigated the effects of the degree of protein fractionation or degree of hydrolysis on the absorption of amino acids and the subsequent hormonal response [ , , , , , ].

Further, the rate of absorption may lead to a more favorable anabolic hormonal environment [ , , ]. Calbet et al. Each of the nitrogen containing solutions contained 15 g of glucose and 30 g of protein.

Results indicated that peptide hydrolysates produced a faster increase in venous plasma amino acids compared to milk proteins. Further, the peptide hydrolysates produced peak plasma insulin levels that were two- and four-times greater than that evoked by the milk and glucose solutions, respectively, with a correlation of 0.

In a more appropriate comparison, Morifuji et al. However, Calbet et al. The hydrolyzed casein, however, did result in a greater amino acid response than the nonhydrolyzed casein. Finally, both hydrolyzed groups resulted in greater gastric secretions, as well as greater plasma increases, in glucose-dependent insulinotropic polypeptides [ ].

Buckley and colleagues [ ] found that a ~ 30 g dose of a hydrolyzed whey protein isolate resulted in a more rapid recovery of muscle force-generating capacity following eccentric exercise, compared with a flavored water placebo or a non-hydrolyzed form of the same whey protein isolate.

In agreement with these findings, Cooke et al. Three and seven days after completing the damaging exercise bout, maximal strength levels were higher in the hydrolyzed whey protein group compared to carbohydrate supplementation.

Additionally, blood concentrations of muscle damage markers tended to be lower when four ~g doses of a hydrolyzed whey protein isolate were ingested for two weeks following the damaging bout. Beyond influencing strength recovery after damaging exercise, other benefits of hydrolyzed proteins have been suggested.

For example, Morifuji et al. Furthermore, Lockwood et al. Results indicated that strength and lean body mass LBM increased equally in all groups.

However, fat mass decreased only in the hydrolyzed whey protein group. While more work needs to be completed to fully determine the potential impact of hydrolyzed proteins on strength and body composition changes, this initial study suggests that hydrolyzed whey may be efficacious for decreasing body fat.

Finally, Saunders et al. The authors reported that co-ingestion of a carbohydrate and protein hydrolysate improved time-trial performance late in the exercise protocol and significantly reduced soreness and markers of muscle damage.

Two excellent reviews on the topic of hydrolyzed proteins and their impact on performance and recovery have been published by Van Loon et al. The prevalence of digestive enzymes in sports nutrition products has increased during recent years with many products now containing a combination of proteases and lipases, with the addition of carbohydrates in plant proteins.

Proteases can hydrolyze proteins into various peptide configurations and potentially single amino acids. It appears that digestive enzyme capabilities and production decrease with age [ ], thus increasing the difficulty with which the body can break down and digest large meals.

Digestive enzymes could potentially work to promote optimal digestion by allowing up-regulation of various metabolic enzymes that may be needed to allow for efficient bodily operation. Further, digestive enzymes have been shown to minimize quality differences between varying protein sources [ ].

Individuals looking to increase plasma peak amino acid concentrations may benefit from hydrolyzed protein sources or protein supplemented with digestive enzymes.

However, more work is needed before definitive conclusions can be drawn regarding the efficacy of digestive enzymes. Despite a plethora of studies demonstrating safety, much concern still exists surrounding the clinical implications of consuming increased amounts of protein, particularly on renal and hepatic health.

The majority of these concerns stem from renal failure patients and educational dogma that has not been rewritten as evidence mounts to the contrary.

Certainly, it is clear that people in renal failure benefit from protein-restricted diets [ ], but extending this pathophysiology to otherwise healthy exercise-trained individuals who are not clinically compromised is inappropriate.

Published reviews on this topic consistently report that an increased intake of protein by competitive athletes and active individuals provides no indication of hepato-renal harm or damage [ , ].

This is supported by a recent commentary [ ] which referenced recent reports from the World Health Organization [ ] where they indicated a lack of evidence linking a high protein diet to renal disease.

Likewise, the panel charged with establishing reference nutrient values for Australia and New Zealand also stated there was no published evidence that elevated intakes of protein exerted any negative impact on kidney function in athletes or in general [ ].

Recently, Antonio and colleagues published a series of original investigations that prescribed extremely high amounts of protein ~3. The first study in had resistance-trained individuals consume an extremely high protein diet 4. A follow-up investigation [ ] required participants to ingest up to 3.

Their next study employed a crossover study design in twelve healthy resistance-trained men in which each participant was tested before and after for body composition as well as blood-markers of health and performance [ ].

In one eight-week block, participants followed their normal habitual diet 2. No changes in body composition were reported, and importantly, no clinical side effects were observed throughout the study. Finally, the same group of authors published a one-year crossover study [ ] in fourteen healthy resistance-trained men.

This investigation showed that the chronic consumption of a high protein diet i. Furthermore, there were no alterations in clinical markers of metabolism and blood lipids. Multiple review articles indicate that no controlled scientific evidence exists indicating that increased intakes of protein pose any health risks in healthy, exercising individuals.

A series of controlled investigations spanning up to one year in duration utilizing protein intakes of up to 2. In alignment with our previous position stand, it is the position of the International Society of Sports Nutrition that the majority of exercising individuals should consume at minimum approximately 1.

The amount is dependent upon the mode and intensity of the exercise, the quality of the protein ingested, as well as the energy and carbohydrate status of the individual. Concerns that protein intake within this range is unhealthy are unfounded in healthy, exercising individuals.

An attempt should be made to consume whole foods that contain high-quality e. The timing of protein intake in the period encompassing the exercise session may offer several benefits including improved recovery and greater gains in lean body mass.

In addition, consuming protein pre-sleep has been shown to increase overnight MPS and next-morning metabolism acutely along with improvements in muscle size and strength over 12 weeks of resistance training.

Intact protein supplements, EAAs and leucine have been shown to be beneficial for the exercising individual by increasing the rates of MPS, decreasing muscle protein degradation, and possibly aiding in recovery from exercise. In summary, increasing protein intake using whole foods as well as high-quality supplemental protein sources can improve the adaptive response to training.

Campbell B, Kreider RB, Ziegenfuss T, La Bounty P, Roberts M, Burke D, et al. International society of sports nutrition position stand: protein and exercise. J Int Soc Sports Nutr. Macdermid PW, Stannard SR. A whey-supplemented, high-protein diet versus a high-carbohydrate diet: effects on endurance cycling performance.

Int J Sport Nutr Exerc Metab. Article CAS PubMed Google Scholar. Burke LM, Hawley JA, Wong SH, Jeukendrup AE. Carbohydrates for training and competition. J Sports Sci. Article PubMed Google Scholar. Witard OC, Jackman SR, Kies AK, Jeukendrup AE, Tipton KD.

Effect of increased dietary protein on tolerance to intensified training. Med Sci Sports Exerc. D'lugos AC, Luden ND, Faller JM, Akers JD, Mckenzie AI, Saunders MJ. Supplemental protein during heavy cycling training and recovery impacts skeletal muscle and heart rate responses but not performance.

Article CAS Google Scholar. Breen L, Tipton KD, Jeukendrup AE. No effect of carbohydrate-protein on cycling performance and indices of recovery. CAS PubMed Google Scholar. Saunders MJ, Moore RW, Kies AK, Luden ND, Pratt CA.

Carbohydrate and protein hydrolysate coingestions improvement of late-exercise time-trial performance. Valentine RJ, Saunders MJ, Todd MK, St Laurent TG. Influence of carbohydrate-protein beverage on cycling endurance and indices of muscle disruption. Van Essen M, Gibala MJ.

Failure of protein to improve time trial performance when added to a sports drink. Article PubMed CAS Google Scholar.

Ivy JL, Res PT, Sprague RC, Widzer MO. Effect of a carbohydrate-protein supplement on endurance performance during exercise of varying intensity.

Saunders MJ, Kane MD, Todd MK. Effects of a carbohydrate-protein beverage on cycling endurance and muscle damage. Saunders MJ, Luden ND, Herrick JE. Consumption of an oral carbohydrate-protein gel improves cycling endurance and prevents postexercise muscle damage.

J Strength Cond Res. PubMed Google Scholar. Romano-Ely BC, Todd MK, Saunders MJ, Laurent TS. Effect of an isocaloric carbohydrate-protein-antioxidant drink on cycling performance.

Beelen M, Zorenc A, Pennings B, Senden JM, Kuipers H, Van Loon LJ. Impact of protein coingestion on muscle protein synthesis during continuous endurance type exercise.

Am J Physiol Endocrinol Metab. Andersen LL, Tufekovic G, Zebis MK, Crameri RM, Verlaan G, Kjaer M, et al. The effect of resistance training combined with timed ingestion of protein on muscle fiber size and muscle strength.

Metab Clin Exp. Bemben MG, Witten MS, Carter JM, Eliot KA, Knehans AW, Bemben DA. The effects of supplementation with creatine and protein on muscle strength following a traditional resistance training program in middle-aged and older men.

J Nutr Health Aging. Burke DG, Chilibeck PD, Davidson KS, Candow DG, Farthing J, Smith-Palmer T. The effect of whey protein supplementation with and without creatine monohydrate combined with resistance training on lean tissue mass and muscle strength.

Denysschen CA, Burton HW, Horvath PJ, Leddy JJ, Browne RW. Resistance training with soy vs whey protein supplements in hyperlipidemic males. Article PubMed PubMed Central CAS Google Scholar.

Erskine RM, Fletcher G, Hanson B, Folland JP. Whey protein does not enhance the adaptations to elbow flexor resistance training. Herda AA, Herda TJ, Costa PB, Ryan ED, Stout JR, Cramer JT.

Muscle performance, size, and safety responses after eight weeks of resistance training and protein supplementation: a randomized, double-blinded, placebo-controlled clinical trial.

Hulmi JJ, Kovanen V, Selanne H, Kraemer WJ, Hakkinen K, Mero AA. Acute and long-term effects of resistance exercise with or without protein ingestion on muscle hypertrophy and gene expression.

Amino Acids. Kerksick CM, Rasmussen CJ, Lancaster SL, Magu B, Smith P, Melton C, et al. The effects of protein and amino acid supplementation on performance and training adaptations during ten weeks of resistance training. Kukuljan S, Nowson CA, Sanders K, Daly RM.

Effects of resistance exercise and fortified milk on skeletal muscle mass, muscle size, and functional performance in middle-aged and older men: an mo randomized controlled trial.

J Appl Physiol Bethesda, Md : Weisgarber KD, Candow DG, Vogt ES. Whey protein before and during resistance exercise has no effect on muscle mass and strength in untrained young adults. Willoughby DS, Stout JR, Wilborn CD.

Effects of resistance training and protein plus amino acid supplementation on muscle anabolism, mass, and strength. Candow DG, Burke NC, Smith-Palmer T, Burke DG. Effect of whey and soy protein supplementation combined with resistance training in young adults.

Cribb PJ, Williams AD, Stathis CG, Carey MF, Hayes A. Effects of whey isolate, creatine, and resistance training on muscle hypertrophy. Hoffman JR, Ratamess NA, Kang J, Falvo MJ, Faigenbaum AD. Article PubMed PubMed Central Google Scholar. Effects of protein supplementation on muscular performance and resting hormonal changes in college football players.

J Sports Sci Med. PubMed PubMed Central Google Scholar. Hida A, Hasegawa Y, Mekata Y, Usuda M, Masuda Y, Kawano H, et al. Effects of egg white protein supplementation on muscle strength and serum free amino acid concentrations.

Moore DR, Robinson MJ, Fry JL, Tang JE, Glover EI, Wilkinson SB, et al. Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. Am J Clin Nutr. Schoenfeld BJ, Aragon AA, Krieger JW.

The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. Josse AR, Tang JE, Tarnopolsky MA, Phillips SM. Body composition and strength changes in women with milk and resistance exercise. Taylor LW, Wilborn C, Roberts MD, White A, Dugan K.

Eight weeks of pre- and postexercise whey protein supplementation increases lean body mass and improves performance in division III collegiate female basketball players.

Appl Physiol Nutr Metab. Cermak NM, Res PT, De Groot LC, Saris WH, Van Loon LJ. Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis.

Pasiakos SM, Mclellan TM, Lieberman HR. The effects of protein supplements on muscle mass, strength, and aerobic and anaerobic power in healthy adults: a systematic review. Sports Med. Rennie MJ. Control of muscle protein synthesis as a result of contractile activity and amino acid availability: implications for protein requirements.

Phillips SM. The science of muscle hypertrophy: making dietary protein count. Proc Nutr Soc. Tipton KD, Phillips SM. Dietary protein for muscle hypertrophy. Nestle Nutrition Institute workshop series.

Layman DK, Evans E, Baum JI, Seyler J, Erickson DJ, Boileau RA. Dietary protein and exercise have additive effects on body composition during weight loss in adult women.

J Nutr. Layman DK, Boileau RA, Erickson DJ, Painter JE, Shiue H, Sather C, et al. A reduced ratio of dietary carbohydrate to protein improves body composition and blood lipid profiles during weight loss in adult women.

Pasiakos SM, Cao JJ, Margolis LM, Sauter ER, Whigham LD, Mcclung JP, et al. Effects of high-protein diets on fat-free mass and muscle protein synthesis following weight loss: a randomized controlled trial. FASEB J. Kerksick C, Thomas A, Campbell B, Taylor L, Wilborn C, Marcello B, et al.

Effects of a popular exercise and weight loss program on weight loss, body composition, energy expenditure and health in obese women. Nutr Metab Lond.

Kerksick CM, Wismann-Bunn J, Fogt D, Thomas AR, Taylor L, Campbell BI, et al. Changes in weight loss, body composition and cardiovascular disease risk after altering macronutrient distributions during a regular exercise program in obese women.

Nutr J. Kreider RB, Serra M, Beavers KM, Moreillon J, Kresta JY, Byrd M, et al. A structured diet and exercise program promotes favorable changes in weight loss, body composition, and weight maintenance. J Am Diet Assoc. Biolo G, Tipton KD, Klein S, Wolfe RR.

An abundant supply of amino acids enhances the metabolic effect of exercise on muscle protein. Am J Phys. CAS Google Scholar. Zawadzki KM, Yaspelkis BB 3rd, Ivy JL. Carbohydrate-protein complex increases the rate of muscle glycogen storage after exercise.

J Appl Physiol. Bethesda, Md : Biolo G, Maggi SP, Williams BD, Tipton KD, Wolfe RR. Increased rates of muscle protein turnover and amino acid transport after resistance exercise in humans. Tipton KD, Ferrando AA, Phillips SM, Doyle D Jr, Wolfe RR. Postexercise net protein synthesis in human muscle from orally administered amino acids.

Burd NA, West DW, Moore DR, Atherton PJ, Staples AW, Prior T, et al. Enhanced amino acid sensitivity of myofibrillar protein synthesis persists for up to 24 h after resistance exercise in young men. Tipton KD, Gurkin BE, Matin S, Wolfe RR. Nonessential amino acids are not necessary to stimulate net muscle protein synthesis in healthy volunteers.

J Nutr Biochem. Borsheim E, Tipton KD, Wolf SE, Wolfe RR. Essential amino acids and muscle protein recovery from resistance exercise. Volpi E, Kobayashi H, Sheffield-Moore M, Mittendorfer B, Wolfe RR. Essential amino acids are primarily responsible for the amino acid stimulation of muscle protein anabolism in healthy elderly adults.

CAS PubMed PubMed Central Google Scholar. Tipton KD, Rasmussen BB, Miller SL, Wolf SE, Owens-Stovall SK, Petrini BE, et al. Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise.

Tipton KD, Borsheim E, Wolf SE, Sanford AP, Wolfe RR. Acute response of net muscle protein balance reflects h balance after exercise and amino acid ingestion. Coffey VG, Moore DR, Burd NA, Rerecich T, Stellingwerff T, Garnham AP, et al.

Nutrient provision increases signalling and protein synthesis in human skeletal muscle after repeated sprints. Eur J Appl Physiol. Breen L, Philp A, Witard OC, Jackman SR, Selby A, Smith K, et al.

The influence of carbohydrate-protein co-ingestion following endurance exercise on myofibrillar and mitochondrial protein synthesis. J Physiol. Ferguson-Stegall L, Mccleave EL, Ding Z, Doerner PG 3rd, Wang B, Liao YH, et al.

Postexercise carbohydrate-protein supplementation improves subsequent exercise performance and intracellular signaling for protein synthesis. Volek JS.

Influence of nutrition on responses to resistance training. Kerksick C, Harvey T, Stout J, Campbell B, Wilborn C, Kreider R, et al.

International society of sports nutrition position stand: nutrient timing. Elliot TA, Cree MG, Sanford AP, Wolfe RR, Tipton KD. Milk ingestion stimulates net muscle protein synthesis following resistance exercise.

Farnfield MM, Breen L, Carey KA, Garnham A, Cameron-Smith D. Activation of mtor signalling in young and old human skeletal muscle in response to combined resistance exercise and whey protein ingestion. Tang JE, Manolakos JJ, Kujbida GW, Lysecki PJ, Moore DR, Phillips SM.

Minimal whey protein with carbohydrate stimulates muscle protein synthesis following resistance exercise in trained young men. Tipton KD. Role of protein and hydrolysates before exercise. Hulmi JJ, Kovanen V, Lisko I, Selanne H, Mero AA. The effects of whey protein on myostatin and cell cycle-related gene expression responses to a single heavy resistance exercise bout in trained older men.

Ivy JL, Ding Z, Hwang H, Cialdella-Kam LC, Morrison PJ. Post exercise carbohydrate-protein supplementation: Phosphorylation of muscle proteins involved in glycogen synthesis and protein translation. Churchward-Venne TA, Murphy CH, Longland TM, Phillips SM.

Role of protein and amino acids in promoting lean mass accretion with resistance exercise and attenuating lean mass loss during energy deficit in humans.

Short-term training: when do repeated bouts of resistance exercise become training? Can J Appl Physiol. Pennings B, Koopman R, Beelen M, Senden JM, Saris WH, Van Loon LJ.

Exercising before protein intake allows for greater use of dietary protein-derived amino acids for de novo muscle protein synthesis in both young and elderly men.

Miller BF, Olesen JL, Hansen M, Dossing S, Crameri RM, Welling RJ, et al. Coordinated collagen and muscle protein synthesis in human patella tendon and quadriceps muscle after exercise. Camera DM, Edge J, Short MJ, Hawley JA, Coffey VG. Early time course of akt phosphorylation after endurance and resistance exercise.

Cribb PJ, Hayes A. Effects of supplement timing and resistance exercise on skeletal muscle hypertrophy. Esmarck B, Andersen JL, Olsen S, Richter EA, Mizuno M, Kjaer M. Timing of postexercise protein intake is important for muscle hypertrophy with resistance training in elderly humans.

Article CAS PubMed PubMed Central Google Scholar. Hoffman JR, Ratamess NA, Tranchina CP, Rashti SL, Kang J, Faigenbaum AD. Effect of protein-supplement timing on strength, power, and body-composition changes in resistance-trained men.

Fujita S, Dreyer HC, Drummond MJ, Glynn EL, Volpi E, Rasmussen BB. Essential amino acid and carbohydrate ingestion before resistance exercise does not enhance postexercise muscle protein synthesis. J Appl Physiol Bird SP, Tarpenning KM, Marino FE. Roberts MD, Dalbo VJ, Hassell SE, Brown R, Kerksick CM.

Effects of preexercise feeding on markers of satellite cell activation. Dalbo VJ, Roberts MD, Hassell S, Kerksick CM. Effects of pre-exercise feeding on serum hormone concentrations and biomarkers of myostatin and ubiquitin proteasome pathway activity.

Eur J Nutr. Tipton KD, Elliott TA, Cree MG, Wolf SE, Sanford AP, Wolfe RR. Ingestion of casein and whey proteins result in muscle anabolism after resistance exercise. Kerksick CM, Leutholtz B. Nutrient administration and resistance training. Burk A, Timpmann S, Medijainen L, Vahi M, Oopik V.

Time-divided ingestion pattern of casein-based protein supplement stimulates an increase in fat-free body mass during resistance training in young untrained men. Nutr Res. Schoenfeld BJ, Aragon A, Wilborn C, Urbina SL, Hayward SE, Krieger J. Pre- versus post-exercise protein intake has similar effects on muscular adaptations.

Aragon AA, Schoenfeld BJ. Nutrient timing revisited: is there a post-exercise anabolic window? Bosse JD, Dixon BM. Dietary protein to maximize resistance training: a review and examination of protein spread and change theories.

Macnaughton LS, Wardle SL, Witard OC, Mcglory C, Hamilton DL, Jeromson S, et al. The response of muscle protein synthesis following whole-body resistance exercise is greater following 40 g than 20 g of ingested whey protein.

Physiol Rep. Tang JE, Moore DR, Kujbida GW, Tarnopolsky MA, Phillips SM. Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise in young men.

J App Physiol Bethesda, Md: West DW, Burd NA, Coffey VG, Baker SK, Burke LM, Hawley JA, et al. Rapid aminoacidemia enhances myofibrillar protein synthesis and anabolic intramuscular signaling responses after resistance exercise.

Geneva: World Health Organization; Series Editor : Who technical report series. Google Scholar. Joy JM, Lowery RP, Wilson JM, Purpura M, De Souza EO, Wilson SM, et al. The effects of 8 weeks of whey or rice protein supplementation on body composition and exercise performance.

Bos C, Metges CC, Gaudichon C, Petzke KJ, Pueyo ME, Morens C, et al. Postprandial kinetics of dietary amino acids are the main determinant of their metabolism after soy or milk protein ingestion in humans.

Burd NA, Yang Y, Moore DR, Tang JE, Tarnopolsky MA, Phillips SM. Greater stimulation of myofibrillar protein synthesis with ingestion of whey protein isolate v. Micellar casein at rest and after resistance exercise in elderly men.

Br J Nutr. Phillips SM, Tang JE, Moore DR. The role of milk- and soy-based protein in support of muscle protein synthesis and muscle protein accretion in young and elderly persons. J Am Coll Nutr. Hartman JW, Tang JE, Wilkinson SB, Tarnopolsky MA, Lawrence RL, Fullerton AV, et al.

Consumption of fat-free fluid milk after resistance exercise promotes greater lean mass accretion than does consumption of soy or carbohydrate in young, novice, male weightlifters. Wilkinson SB, Tarnopolsky MA, Macdonald MJ, Macdonald JR, Armstrong D, Phillips SM. Consumption of fluid skim milk promotes greater muscle protein accretion after resistance exercise than does consumption of an isonitrogenous and isoenergetic soy-protein beverage.

Kerksick CM, Rasmussen C, Lancaster S, Starks M, Smith P, Melton C, et al. Impact of differing protein sources and a creatine containing nutritional formula after 12 weeks of resistance training. Paddon-Jones D, Sheffield-Moore M, Aarsland A, Wolfe RR, Ferrando AA.

Exogenous amino acids stimulate human muscle anabolism without interfering with the response to mixed meal ingestion. Paddon-Jones D, Sheffield-Moore M, Urban RJ, Sanford AP, Aarsland A, Wolfe RR, et al. Essential amino acid and carbohydrate supplementation ameliorates muscle protein loss in humans during 28 days bedrest.

J Clin Endocrinol Metab. Phillips SM, Tipton KD, Aarsland A, Wolf SE, Wolfe RR. Mixed muscle protein synthesis and breakdown after resistance exercise in humans.

Rennie MJ, Bohe J, Wolfe RR. Latency, duration and dose response relationships of amino acid effects on human muscle protein synthesis. Svanberg E, Jefferson LS, Lundholm K, Kimball SR.

Postprandial stimulation of muscle protein synthesis is independent of changes in insulin. Trommelen J, Groen BB, Hamer HM, De Groot LC, Van Loon LJ. Mechanisms in endocrinology: exogenous insulin does not increase muscle protein synthesis rate when administered systemically: a systematic review.

Eur J Endocrinol. Abdulla H, Smith K, Atherton PJ, Idris I. Role of insulin in the regulation of human skeletal muscle protein synthesis and breakdown: a systematic review and meta-analysis.

Greenhaff PL, Karagounis LG, Peirce N, Simpson EJ, Hazell M, Layfield R, et al. Disassociation between the effects of amino acids and insulin on signaling, ubiquitin ligases, and protein turnover in human muscle.

Rennie MJ, Bohe J, Smith K, Wackerhage H, Greenhaff P. Branched-chain amino acids as fuels and anabolic signals in human muscle.

Power O, Hallihan A, Jakeman P. Human insulinotropic response to oral ingestion of native and hydrolysed whey protein. Staples AW, Burd NA, West DW, Currie KD, Atherton PJ, Moore DR, et al.

Carbohydrate does not augment exercise-induced protein accretion versus protein alone. Baron KG, Reid KJ, Kern AS, Zee PC.

Role of sleep timing in caloric intake and bmi. Obesity Silver Spring. Article Google Scholar. Ormsbee MJ, Gorman KA, Miller EA, Baur DA, Eckel LA, Contreras RJ, et al. Nighttime feeding likely alters morning metabolism but not exercise performance in female athletes.

Zwaan M, Burgard MA, Schenck CH, Mitchell JE. Night time eating: a review of the literature. Eur Eat Disord Rev. Kinsey AW, Ormsbee MJ. The health impact of nighttime eating: old and new perspectives.

Trommelen J, Van Loon LJ. Pre-sleep protein ingestion to improve the skeletal muscle adaptive response to exercise training. Res PT, Groen B, Pennings B, Beelen M, Wallis GA, Gijsen AP, et al. Protein ingestion before sleep improves postexercise overnight recovery.

Groen BB, Res PT, Pennings B, Hertle E, Senden JM, Saris WH, et al. Intragastric protein administration stimulates overnight muscle protein synthesis in elderly men. Madzima TA, Panton LB, Fretti SK, Kinsey AW, Ormsbee MJ. Night-time consumption of protein or carbohydrate results in increased morning resting energy expenditure in active college-aged men.

Kinsey AW, Eddy WR, Madzima TA, Panton LB, Arciero PJ, Kim JS, et al. Influence of night-time protein and carbohydrate intake on appetite and cardiometabolic risk in sedentary overweight and obese women.

Kinsey AW, Cappadona SR, Panton LB, Allman BR, Contreras RJ, Hickner RC, et al. The effect of casein protein prior to sleep on fat metabolism in obese men.

Ormsbee MJ, Kinsey AW, Eddy WR, Madzima TA, Arciero PJ, Figueroa A, et al. The influence of nighttime feeding of carbohydrate or protein combined with exercise training on appetite and cardiometabolic risk in young obese women. Figueroa A, Wong A, Kinsey A, Kalfon R, Eddy W, Ormsbee MJ. Effects of milk proteins and combined exercise training on aortic hemodynamics and arterial stiffness in young obese women with high blood pressure.

Am J Hypertens. Dirks ML, Groen BB, Franssen R, Van Kranenburg J, Van Loon LJ. Neuromuscular electrical stimulation prior to presleep protein feeding stimulates the use of protein-derived amino acids for overnight muscle protein synthesis.

Holwerda AM, Kouw IW, Trommelen J, Halson SL, Wodzig WK, Verdijk LB, et al. Physical activity performed in the evening increases the overnight muscle protein synthetic response to presleep protein ingestion in older men. Trommelen J, Holwerda AM, Kouw IW, Langer H, Halson SL, Rollo I, et al.

Resistance exercise augments postprandial overnight muscle protein synthesis rates. Snijders T, Res PT, Smeets JS, Van Vliet S, Van Kranenburg J, Maase K, et al. Protein ingestion before sleep increases muscle mass and strength gains during prolonged resistance-type exercise training in healthy young men.

Antonio J, Ellerbroek A, Peacock C, Silver T. Casein protein supplementation in trained men and women: morning versus evening. Int J Exerc Sci. Buckner SL, Leonneke JP, Loprinzi PD. Protein timing during the day and its relevance for muscle strength and lean mass.

Clin Physiol Funct Imaging. doi: Mitchell CJ, Churchward-Venne TA, Parise G, Bellamy L, Baker SK, Smith K, et al. Acute post-exercise myofibrillar protein synthesis is not correlated with resistance training-induced muscle hypertrophy in young men. PLoS One.

Areta JL, Burke LM, Ross ML, Camera DM, West DW, Broad EM, et al. Timing and distribution of protein ingestion during prolonged recovery from resistance exercise alters myofibrillar protein synthesis. Arnal MA, Mosoni L, Boirie Y, Houlier ML, Morin L, Verdier E, et al. Protein feeding pattern does not affect protein retention in young women.

Tinsley GM, Forsse JS, Butler NK, Paoli A, Bane AA, La Bounty PM, et al. Time-restricted feeding in young men performing resistance training: a randomized controlled trial.

Eur J Sport Sci. Tarnopolsky MA, Macdougall JD, Atkinson SA. Influence of protein intake and training status on nitrogen balance and lean body mass. Phillips SM, Atkinson SA, Tarnopolsky MA, Macdougall JD. Gender differences in leucine kinetics and nitrogen balance in endurance athletes.

Lemon PW. Effect of exercise on protein requirements. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool. Heterogeneity was tested using the I 2 statistic index.

Results: Twenty RCTs were included with a total of subjects. The results showed that dietary supplements had no effect on muscle strength, CSA, muscle fiber type distribution, peak aerobic capacity or muscle volume. But dietary supplements have a protective effect on the lean mass of the legs.

Conclusion: Dietary supplements can improve lean leg mass, but did not show a tendency to have an effect on muscle strength, CSA, muscle fiber type distribution, peak aerobic capacity or muscle volume during muscle disuse.

Patients recovering from an illness or injury usually require a period of bed rest or limb immobilization. However even a short period of inactivity can result in a significant loss of skeletal muscle mass and strength 1 , 2 , which might lead to a longer recovery period and a higher risk of disease recurrence 3 — 6.

Skeletal muscle is the most abundant tissue in the body, and when it atrophies, it affects the metabolism throughout the body, such as reduced insulin sensitivity 7 , 8 , decreased basal metabolic rate 9 , and increased body fat mass These factors will affect body functions and result in more serious health problems.

Therefore, it is necessary to take measures to prevent loss of muscle mass and strength during periods of inactivity. It is well known that exercise is the best way to maintain and increase muscle mass 11 — However, in many cases, patients are not allowed to exercise, so other methods are needed to prevent skeletal muscle atrophy.

Loss of skeletal muscle mass due to muscle disuse is attributed to a long-term imbalance between muscle protein synthesis and catabolic rates. A decrease in the basal muscle protein synthesis rate has been reported following bed rest 14 , 15 and limb immobilization 16 , Previous studies found that supplementation with nutrients, such as dietary protein and essential amino acids, can reduce muscle loss and increase muscle growth during immobilization and aging by stimulating muscle protein synthesis The growth of skeletal muscle is traditionally referred to as skeletal muscle hypertrophy, which is manifested as an increase in muscle mass, muscle thickness, muscle area, muscle volume, and muscle fiber cross-sectional area CSA However, it remains unclear about the effect of dietary supplements on disuse muscular atrophy.

Some randomized controlled trials RCTs showed that nutritional supplementation protected against skeletal muscle atrophy during disuse 20 , 21 , while some RCTs have showed the opposite results 22 , Therefore, a meta-analysis of existing RCTs is necessary to provide updated evidence on the effectiveness of dietary supplements in the treatment of disuse muscular atrophy.

This review follows the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and the Cochrane collaboration for systematic reviews It answers the following research question: Do dietary supplements prevent loss of muscle mass and strength during muscle disuse?

The study is registered on PROSPERO, and the registration number is CRD We searched the PubMed, Embase, Cochrane, Scopus, Web of Science, CINAHL databases for RCTs assessing the effect of dietary supplements on disuse muscular atrophy from the year of inception to December 15, with no language restrictions.

The search terms were disused muscle atrophy OR skeletal muscle disuse atrophy OR muscle disuse OR disuse atrophy OR muscle disuse atrophy OR disuse atrophies OR immobilization OR immobilization-induced atrophy OR bed rest OR bed rests OR rest, bed OR rests, bed AND dietary supplements OR diet therapy OR nutrition therapy OR dietary supplement OR supplements, dietary OR dietary supplementations OR supplementations, dietary OR food supplementations OR food supplements OR food supplement OR supplement, food OR supplements, food OR therapy, nutrition OR nutrition OR diet therapies OR therapy, diet AND randomized controlled trial OR controlled trial OR clinical trial.

The detailed search strategy was shown in Supplementary Table S1. Furthermore, we manually searched the reference lists of eligible studies to identify additional studies. Two authors J-MY, YL independently screened and selected the studies, with disagreements resolved by a third author HY. The inclusion criteria for the studies were based on the PICOS patients, intervention, comparison, outcomes, and study design principle 25 , as shown below:.

Patients P : Healthy subjects who were immobilized lower extremity or on prolonged bed rest according to experimental needs. Intervention I : Nutritional supplements were available in capsules, tablets, liquid, powder form, or supplements were added to the daily diet. Relevant data were extracted from the included studies: 1 name of first author; 2 year of publication; 3 study population; 4 number of participants in the intervention and control groups; 5 type of dietary supplements; 6 dietary supplement dosage and duration; 7 age, sex and body mass index of study participants; 8 differences mean and standard deviation SD of muscle strength, leg lean mass, CSA, fiber type distribution, peak aerobic capacity, and muscle volume between control and intervention groups.

If mean and SD of the differences were not available, we first tried to contact the authors. After no response, we extracted the mean and SD of the pre-intervention and post-intervention values for the control and intervention groups.

html was used to extract the mean and SD. Data were extracted independently by two authors YL, HY , and disagreements were resolved by a third author J-MY. The methodological quality of the included studies was assessed independently by two raters Y-BZ, YL using the Physiotherapy Evidence Database PEDro scale, with discrepancies resolved via discussion with a third rater FG.

The PEDro scale consists of 11 items encompassing external validity Item 1 , internal validity Items 2 to 9 , and statistical reporting Items 10 to Items are rated yes or no 1 or 0 according to whether the criterion is clearly satisfied in the study.

A total PEDro score is achieved by adding the ratings of Items 2 to 11 for a combined total score between 0 and In addition, we assessed the quality of each outcome according to the Grading of Recommendations Assessment Development and Evaluation GRADE criteria 27 , assigning ratings of very low, low, moderate, and high, which involved assessing five domains, including risk of bias, directness of evidence, consistency, precision of results, publication bias.

The risk of bias for the included RCTs was assessed independently by two authors J-HZ, YL using the Cochrane Collaboration Network's Risk of Bias tool The following items were assessed for each study: 1 random sequence generation, 2 allocation concealment, 3 blinding of participants and personnel, 4 blinding of outcome assessment, 5 incomplete outcome data, 6 selective reporting, and 7 other bias.

According to the Cochrane Handbook recommendations, each item was classified as low risk, high risk not fulfilling the criteria or unclear risk specific details or descriptions were not reported , and disagreements were discussed with and resolved by a third author FG.

Statistical analysis was performed using Review Manager 5. The mean and SD of differences, sample size were input into the statistical software. If the median was provided in the article, the median was considered as the mean value.

According to the Cochrane Handbook, the choice of WMD and SMD depends on whether the outcome index evaluation criteria are the same, and WMD is chosen when they are the same, while SMD is chosen when they are not.

In addition, subgroup analyses were performed to assess whether the results differed across conditions, and sensitivity analyses were performed to assess the robustness of the results. The flow chart of study selection was shown in Figure 1. After systematic search from the six databases and other sources, studies were identified.

Of which remained after removing duplicates literature. Then, after screening the titles and abstracts of the articles, irrelevant articles were excluded, and 57 were left. The list of literatures exclusion and reasons for exclusion are shown in Supplementary Table S2.

The characteristics of the 20 included RCTs were shown in Table 1. Details of the composition, dose and duration of dietary supplementation performed daily in each study were shown in Table 1.

Outcome indicators for only two of the twenty RCTs were expressed as mean and SD 39 , The outcome indicators of the other eighteen RCTs were expressed as mean and SE 20 , 21 , 23 , 31 — 38 , 40 — 44 , 46 , There are a total of seven studies for the outcome indicator of muscle strength gave the mean and SD of differences 20 , 21 , 35 , 36 , 40 — 42 , the eight RCTs did not give, and we calculated SD of differences by the Equation 1 31 — 34 , 37 — 39 , For the outcome indicator of leg lean mass, there are six RCTs gave the mean and SD of differences 20 , 36 , 41 , 42 , 44 , 46 , and three RCTs did not give 39 , 43 , 47 , we calculate the SD of difference according to Equation 1.

For the outcome indicator of CSA, two RCTs had mean and SD of differences 40 , 45 , and five RCTs were calculated by Equation 1 to obtain the SD of difference 31 , 32 , 34 , 37 , For the outcome indicator of muscle fiber distribution, the SD of the difference of all four RCTs was calculated 31 — For the outcome indicator of peak aerobic capacity, three RCTs gave the mean and SD of differences 20 , 21 , 36 , the SD of difference was calculated for the two RCTs 33 , For muscle volume, two RCTs gave the mean and SD of differences 39 , 45 , the SD of difference was calculated for the two RCTs 23 , The data for the six RCTs were presented as pictures in the article, and we extracted the mean and SD by using the WebPlot Digitizer tool 33 , 34 , 38 , 40 , 42 , In total, fifteen RCTs measured muscle strength as an outcome indicator.

Muscle strength was measured in two ways. Ten RCTs measured knee extensor muscles isometric torque by isokinetic dynamometry 20 , 21 , 33 , 35 — 40 , 42 , while the other five RCTs measured knee extension strength by performing one repetition of the maximum strength test on the leg extension machine 31 , 32 , 34 , 41 , For the measurement of the lean mass of the legs were all used dual-energy x-ray absorptiometry 20 , 36 , 39 , 41 — 44 , 46 , Seven studies reported CSA as an outcome indicator, three of which used CT for detection 31 , 32 , 34 , three studies used MRI for detection 37 , 39 , 45 , and one was detected using Stratec XCT pQCT with software version 6.

Outcome indicators of fiber type distribution were taken from the vastus lateralis muscle and then muscle biopsy was performed 31 — Peak muscle aerobic capacity for the four RCTs was measured by a graded exercise test on a cycle ergometer and metabolic cart 20 , 21 , 33 , Another RCT measure of peak aerobic capacity was the single-leg ramp exercise test The muscle volume was all measured by MRI 23 , 38 , 39 , The methodological quality of the included studies was shown in Table 1 and Supplementary Table S3.

Eight studies 20 , 21 , 31 , 33 , 34 , 38 , 41 , 45 were rated as good quality. The results indicated insufficient level of concealed allocation, and the sample sizes included in the study were small.

The GRADE evidence for the outcome indicators was rated as low, as detailed in Table 2. Table 2. GRADE evidence profile for outcomes among trials included in the systematic review.

The risk of bias of the 20 included studies was shown in Figure 2. Twelve studies were rated as high risk of bias for selection bias because they only mentioned the randomization but did not specify which method was used for random assignment 20 , 31 — 37 , 41 , 42 , 44 , Information on allocation concealment was not available in sixteen studies and was therefore rated as unclear risk of bias 20 , 21 , 23 , 31 — 37 , 41 , 43 — Most of the studies on performance bias and detection bias were described as double-blinded and therefore rated as low risk, while those not described were rated as unclear risk of bias.

Nine studies' reporting bias were rated as low risk because the study protocols were consistent with the outcome indicators in the studies 20 , 21 , 23 , 31 , 32 , 41 — 43 , And ten studies were rated as unclear risk of bias when there is no enough information about selective reporting 33 — 40 , 44 , Other risks of bias that were not mentioned or could not be judged according to the study and were rated as unclear risks.

The results of the sensitivity analysis were shown in Supplementary Figure S3. Figure 2. Risk of bias graph and summary of included studies.

The figure A risk of bias graph shows the overall risk of bias in each domain. The figure B risk of bias summary indicates the risk of bias in each domain for each study. A total of 15 studies measured muscle strength 20 , 31 — Overall meta-analysis showed that dietary supplements had no protective effect on muscle strength during muscle disuse SMD: 0.

As the types of dietary supplements in both intervention group and control group were heterogenous among the included studies, we performed subgroup analysis to test the effect of different types of dietary supplements on muscle strength.

Firstly, we divided the dietary supplements in the intervention group into protein, amino acid, and other nutrients. Other nutrients include β-hydroxy-β-methylbutyric acid, creatine and Omega-3 fatty acids. The results of subgroup analysis Figure 3 showed that neither protein SMD: 0.

In addition, we performed a subgroup analysis based on the use of placebo and non-placebo in the control group. Supplementary Figure S1 showed that the use of different supplement types in the control group had no effect on the results.

Figure 3. A total of 9 studies reported on leg lean mass as an outcome indicator 20 , 36 , 39 , 41 — 44 , 46 , Overall meta-analysis showed that dietary supplements had protective effect on leg lean mass during muscle disuse WMD: 0. As the types of dietary supplements in both intervention group and control group were heterogenous among the included studies, we performed subgroup analysis to test the effect of different types of dietary supplements on leg lean mass.

We divided the dietary supplements in the intervention group into protein, amino acid, and other nutrients. But the protein group had only one article and meta-analysis was not possible The results of subgroup analysis Figure 4 showed that the amino acid group significantly improved the lean mass of the legs WMD: 0.

Supplementary Figure S2 showed that the use of different supplement types in the control group had no effect on the results. Figure 4. The results of the meta-analysis of CSA and muscle fiber type distribution are shown in Figure 5. When skeletal muscle atrophy occurs, the CSA becomes smaller.

Dietary supplement group did not exhibit greater CSA compared to the control group SMD: 0. When skeletal muscle atrophy occurs, type I muscle fibers are converted to type II muscle fibers 48 , And then the distribution of type I and type II muscle fibers was altered.

As shown in Figure 5 , dietary supplementation had no effect on the distribution of type I WMD: 1. Figure 5. When skeletal muscle atrophy occurs, the peak aerobic capacity of the muscle becomes poor. In this systematic review and meta-analysis, we included 20 RCTs with a total of subjects to analyze whether dietary supplements prevent loss of skeletal muscle mass and strength during muscle disuse.

The results of the meta-analysis showed that dietary supplements had no effect on muscle strength, but could improve the lean mass of the legs.

For the two primary outcome indicators, muscle strength and lean mass, we performed subgroup analysis based on different types of supplements in the control and intervention groups. The results of all subgroup analyses of muscle strength showed that protein, amino acids and other dietary supplements did not improve muscle strength during muscle disuse.

Subgroup analyses of leg lean mass showed that the amino acid group significantly improved lean leg mass during muscle disuse, but the other group did not show an effect. However, their total result was that dietary supplements could improve leg lean mass during muscle disuse.

This may be related to the relatively small number of studies in the other group. Our results did not support dietary supplementation had effect on secondary outcome indicators including CSA, muscle fiber type distribution, peak aerobic capacity and muscle volume.

Transient muscle disuse after injury or during recovery from disease results in a loss of muscle mass and function, including a progressive decrease in muscle strength, lean muscle mass, muscle volume, aerobic capacity, CSA, atrophy of type I muscle fibers and a shift from type I to type II muscle fibers It is accompanied by many other negative health consequences, such as reduced insulin sensitivity 7 , 8 , decreased basal metabolic rate 9 , and increased body fat mass Therefore, it is important to find a safe and effective measure to alleviate skeletal muscle atrophy during muscle disuse.

Our findings suggest that dietary supplementation can play a role in maintaining lean body mass during muscle disuse. Dietary supplements may be considered to maintain lean muscle mass when patients are unable to exercise during muscle disuse. Overall, the risk of bias in our included RCTs was low, and the heterogeneity of the outcome indicators was small.

Therefore, our conclusions may provide some guidance for clinical practice. To our knowledge, this is the first systematic review and meta-analysis of the role of nutritional interventions on disuse muscular atrophy.

Our results are consistent with previously published systematic reviews of nutritional interventions for elderly or sarcopenic patients, where nutritional supplementation alone had no effect on muscle strength 51 — This may be related to the fact that muscle strength is determined by many factors, such as neuromuscular control and muscle mass.

However, studies have found that nutritional interventions combined with exercise training can improve muscle strength and physical function 53 — Therefore, we recommend that nutritional supplementation combined with exercise training interventions should be performed to improve muscle strength after the release of exercise contraindications.

For lean mass, the results of our meta-analysis are inconsistent with previously published systematic reviews of nutrition interventions in older adults 52 , 57 , which may be related to the different populations we included.

Our systematic review included healthy subjects, whereas their systematic review included older adults, whose body composition would have changed. However, this study has some limitations. Firstly, the sample sizes of the included studies in the systematic review were relatively small.

Secondly, the number of studies on outcome indicators such as CSA, muscle fiber type distribution, peak aerobic capacity and muscle volume was relatively small. Third, the number of studies for subgroup analysis was also small. Fourth, some of the RCTs we included do not directly give the SD of the difference, which we calculated by the formula and may differ from the actual value.

In addition, some of the outcome indicators are presented in the form of pictures, and the results we obtained by using the WebPlot Digitizer tool to extract the mean and SD may also be different from the actual values.

Fifth, the types of dietary supplements in both intervention group and control group were heterogenous among the included studies. Therefore, more RCTs with larger sample sizes are needed in the future to validate the effects of dietary supplements on these outcome indicators.

Dietary supplements can improve the lean mass of the legs during muscle disuse. However, our results do not support the role for dietary supplements on muscle strength, CSA, muscle fiber type distribution, peak aerobic capacity or muscle volume. Conception and design and drafted the manuscript: HY, J-MY, and Y-BZ.

Collection and analysis of the data: YLu, YLo, and J-HZ. Final approval of the article: FG and M-YW. All authors contributed to the article and approved the submitted version. This study was supported by the National Science Foundation of Jiangxi Province, China grant number BAB and the Postgraduate Innovation Special Fund Project of Jiangxi Province, China grant number YCS The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers.

Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher. Supplementary Figure S1. Supplementary Figure S2. Supplementary Figure S3. Suetta C, Hvid LG, Justesen L, Christensen U, Neergaard K, Simonsen L, et al.

Effects of aging on human skeletal muscle after immobilization and retraining. J Appl Physiol. doi: PubMed Abstract CrossRef Full Text Google Scholar.

Wall BT, Dirks ML, Snijders T, Senden JM, Dolmans J, Van Loon LJ. Substantial skeletal muscle loss occurs during only 5 days of disuse. Acta physiologica. Stevens JE, Walter GA, Okereke E, Scarborough MT, Esterhai JL, George SZ, et al.

Muscle adaptations with immobilization and rehabilitation after ankle fracture. Med Sci Sports Exerc. Vandenborne K, Elliott MA, Walter GA, Abdus S, Okereke E, Shaffer M, et al.

Longitudinal study of skeletal muscle adaptations during immobilization and rehabilitation. Muscle Nerve. Yu A, Xie Y, Zhong M, Wang F, Huang H, Nie L, et al.

Comparison of the initiation time of enteral nutrition for critically Ill patients: at admission vs. Emerg Med Int.

The 8 Best Supplements for Muscle Growth You Should Try Right Now Once TGs enter the mitochondria, they get broken down for energy. Subgroup analyses of leg lean mass showed that the amino acid group significantly improved lean leg mass during muscle disuse, but the other group did not show an effect. Timing of postexercise protein intake is important for muscle hypertrophy with resistance training in elderly humans. Am J Cli Nutr. Research has demonstrated that the addition of protein in the form of milk and whey protein isolate 0. The three branched-chain amino acids BCAAs are leucine, isoleucine, and valine. However, it is worth noting that, although not statistically significant, the morning group added 0.
The 6 Best Supplements to Gain Muscle The majority of available science has explored the efficacy of ingesting single protein sources, but evidence continues to mount that combining protein sources may afford additional benefits [ ]. Refueling after exercise is also essential. Fourth, some of the RCTs we included do not directly give the SD of the difference, which we calculated by the formula and may differ from the actual value. Saunders MJ, Moore RW, Kies AK, Luden ND, Pratt CA. Rachel MacPherson, BA, CPT.
Workout Supplements Contemporary issues in propdr requirements and consumption for Vegetarian detox diets trained athletes. Therefore, it is necessary to prreservation measures to prevent loss of muscle mass and Iron deficiency and injury risk in athletes during periods of inactivity. Other supplements contain protein isolated from eggs, split peas, rice, and hemp seeds. A recent study in the journal Nutrients suggests a daily intake of 1 to 1. Heterogeneity was tested using the I 2 statistic index. Your diet also plays a role in building muscle mass.
The dietary supplement fighting muscle loss and promoting healthy ageing

Creatine is probably the single best supplement for muscle gain. Many studies have confirmed that it can help increase muscle mass. Specifically, to gain muscle, you need to consume more protein than your body breaks down through natural processes. If this sounds like you, you may want to consider taking a protein supplement.

There are many different protein supplements available, but some of the most popular are whey, casein, and soy protein. Other supplements contain protein isolated from eggs, split peas, rice, and hemp seeds. Research shows that adding extra protein via supplements causes slightly more muscle gain in people who exercise than adding extra carbs.

Many people wonder how much protein to eat daily. If you are an active individual trying to gain muscle, 0. Consuming enough protein is absolutely essential for optimal muscle gain. However, if you are getting enough protein in your diet, taking a protein supplement is unnecessary.

Weight gainers are supplements designed to conveniently help you get more calories and protein. However, most of the calories actually come from carbs. There are often 75— g of carbs, 20—60 g of protein, and 0—15 g of fat per serving in these high calorie supplements.

Some older research in physically inactive adults has shown that drastically increasing calories can increase lean mass like muscle, as long as you eat enough protein.

However, research in adults who weight trained indicated that consuming a weight gainer supplement may not be effective for increasing lean mass. Overall, weight gainers are only recommended if you are struggling to eat enough food and you find it easier to drink a weight gainer shake than eat more real food.

Weight gainers are high calorie products designed to help you consume more calories and protein. However, they are only recommended if you struggle to get enough calories from food. Beta-alanine is an amino acid that reduces fatigue and may improve exercise performance.

Additionally, beta-alanine may help increase muscle mass if you are following an exercise program. One study showed that taking 4 g of beta-alanine per day for 8 weeks increased lean body mass more than a placebo in college wrestlers and football players.

Another older study reported that adding a beta-alanine supplement to a 6-week, high intensity interval training program increased lean body mass by about 1 lb. Therefore, more research is needed to understand the potential benefits of beta-alanine supplementation.

Beta-alanine is an amino acid that can improve exercise performance. Some evidence shows that it may also help increase muscle mass in response to exercise, but more research is needed. Branched-chain amino acids BCAAs consist of three individual amino acids: leucine, isoleucine, and valine.

They are found in most protein sources, particularly those of animal origin like meat, poultry, eggs, dairy, and fish. A small amount of research has shown that BCAAs may improve muscle gain or reduce muscle loss, compared to a placebo. However, other research shows that BCAAs may not preserve lean body mass in people following a weight loss program.

Although they may be beneficial if your diet is inadequate, more information is needed before BCAAs are recommended as a go-to supplement for muscle gain. Branched-chain amino acids are important for muscle growth. They are found in many foods, and it is unclear if taking them as a supplement is helpful when you already consume enough protein.

HMB is responsible for some of the beneficial effects of protein and leucine in the diet. While HMB is produced naturally by your body, taking it as a supplement allows for higher levels and may benefit your muscles.

Several studies in previously untrained adults have shown taking 3—6 g of HMB per day can improve the gains in lean body mass from weight training. However, other research shows that similar doses of HMB are probably not effective at increasing muscle mass in athletes or adults with weight training experience.

This may mean that HMB is most effective for those who are getting started with exercise or increasing the intensity of their workouts. HMB may help increase muscle mass in those who are beginning a weight training program, but it appears to be less effective for those with training experience. Several other supplements claim to increase muscle mass.

These include conjugated linoleic acid, testosterone boosters, glutamine , and carnitine. Many types of supplements claim to increase muscle mass, but there is little evidence that they are effective for healthy, active individuals. To gain muscle, you need to eat enough calories and protein, as well as exercise, ideally with weights.

Once your nutrition and exercise regimens are in check, you may want to consider dietary supplements. Creatine and protein supplements are likely the most effective choices for muscle gain, but other supplements may be beneficial for certain people.

Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available. While diet and exercise are important for gaining weight, certain supplements may also help.

This article examines types of supplements that may be…. Pre-workout supplements are designed to help you gain muscle by allowing you to work out harder and longer. Here are the 10 best pre-workout….

Glutamine is an important amino acid. This article discusses the benefits, uses and side effects of glutamine supplements. MindBodyGreen provides third-party-tested supplements made with high quality ingredients. Our testers and dietitians discuss whether MindBodyGreen…. Vitamins are for athletes to stay healthy.

You may get all you need from the food you eat. However, maximal stimulation of MPS, which results in higher net muscle protein accretion, is the product of the total amount of EAA in circulation as well as the pattern and appearance rate of aminoacidemia that modulates the MPS response [ 86 ].

Recent work has clarified that whey protein provides a distinct advantage over other protein sources including soy considered another fast absorbing protein and casein a slower acting protein source on acute stimulation of MPS [ 86 , 87 ].

Importantly, an elegant study by West and investigators [ 87 ] sought to match the delivery of EAAs in feeding patterns that replicated how whey and casein are digested.

The authors reported that a 25 g dose of whey protein that promoted rapid aminoacidemia further enhanced MPS and anabolic signaling when compared to an identical total dose of whey protein when delivered as ten separate 2. The advantages of whey protein are important to consider, particularly as all three sources rank similarly in assessments of protein quality [ 88 ].

In addition to soy, other plant sources e. have garnered interest as potential protein sources to consider.

Unfortunately, research that examines the ability of these protein sources to modulate exercise performance and training adaptations is limited at this time. The investigators concluded that gains in strength, muscle thickness and body composition were similar between the two protein groups, suggesting that rice protein may be a suitable alternative to whey protein at promoting resistance training adaptations.

Furthermore, differences in absorption kinetics, and the subsequent impact on muscle protein metabolism appear to extend beyond the degree of hydrolysis and amino acid profiles [ 69 , 86 , 90 , 91 , 92 , 92 ].

For instance, unlike soy more of the EAAs from whey proteins hydrolysates and isolates survive splanchnic uptake and travel to the periphery to activate a higher net gain in muscle [ 86 ]. These characteristics yield a high concentration of amino acids in the blood aminoacidemia [ 69 , 87 ] that facilitates greater activation of MPS and net muscle protein accretion, in direct comparison to other protein choices [ 50 , 69 , 91 ].

The addition of creatine to whey protein supplementation appears to further augment these adaptations [ 27 , 72 , 95 ]; however, an optimal timing strategy for this combination remains unclear.

The timing of protein-rich meals consumed throughout a day has the potential to influence adaptations to exercise. Using similar methods, other studies over recent decades [ 53 , 62 , 87 , 91 , 96 , 97 , 98 , 99 , ] have established the following:.

The anabolic response to feeding is pronounced but transient. During the post-prandial phase 1—4 h after a meal MPS is elevated, resulting in a positive muscle protein balance.

In contrast, MPS rates are lower in a fasted state and muscle protein balance is negative. Protein accretion only occurs in the fed state. The concentration of EAA in the blood plasma regulates protein synthesis rates within muscle at rest and post exercise.

More recent work has established that protein-carbohydrate supplementation after strenuous endurance exercise stimulates contractile MPS via similar signaling pathways as resistance exercise [ 56 , 57 ]. That is, the consumption of a protein-containing meal up to 24 h after a single bout of resistance exercise results in a higher net stimulation of MPS and protein accretion than the same meal consumed after 24 h of inactivity [ 50 ].

The effect of insulin on MPS is dependent on its ability to increase amino acid availability, which does not occur when insulin is systematically increased e. Taken together, these results seem to indicate that post-workout carbohydrate supplementation offers very little contribution from a muscle development standpoint provided adequate protein is consumed.

Importantly, these results are not to be interpreted to mean that carbohydrate administration offers no potential effect for an athlete engaging in moderate to high volumes of training, but rather that benefits derived from carbohydrate administration appear to more favorably impact aspects of muscle glycogen recovery as opposed to stimulating muscle protein accretion.

Eating before sleep has long been controversial [ , , ]. However, a methodological consideration in the original studies such as the population used, time of feeding, and size of the pre-sleep meal confounds firm conclusions about benefits or drawbacks.

Results from several investigations indicate that 30—40 g of casein protein ingested min prior to sleep [ ] or via nasogastric tubing [ ] increased overnight MPS in both young and old men, respectively. Likewise, in an acute setting, 30 g of whey protein, 30 g of casein protein, and 33 g of carbohydrate consumed min prior to sleep resulted in an elevated morning resting metabolic rate in young fit men compared to a non-caloric placebo [ ].

Interestingly, Madzima et al. This infers that casein protein consumed pre-sleep maintains overnight lipolysis and fat oxidation. This finding was further supported by Kinsey et al. Similar to Madzima et al. Interestingly, the pre-sleep protein and carbohydrate ingestion resulted in elevated insulin concentrations the next morning and decreased hunger in this overweight population.

Of note, it appears that exercise training completely ameliorates any rise in insulin when eating at night before sleep [ ], while the combination of pre-sleep protein and exercise has been shown to reduce blood pressure and arterial stiffness in young obese women with prehypertension and hypertension [ ].

In athletes, evening chocolate milk consumption has also been shown to influence carbohydrate metabolism in the morning, but not running performance [ ]. In addition, data supports that exercise performed in the evening augments the overnight MPS response in both younger and older men [ , , ].

To date, only a few studies involving nighttime protein ingestion have been carried out for longer than four weeks. Snijders et al. The group receiving the protein-centric supplement each night before sleep had greater improvements in muscle mass and strength over the week study.

Of note, this study was non-nitrogen balanced and the protein group received approximately 1. More recently, in a study in which total protein intake was equal, Antonio et al. They examined the effects on body composition and performance [ ].

All subjects maintained their usual exercise program. The authors reported no differences in body composition or performance between the morning and evening casein supplementation groups. However, it is worth noting that, although not statistically significant, the morning group added 0.

Although this finding was not statistically significant, it supports data from Burk et al. It should be noted that the subjects in the Burk et al.

study were resistance training. A retrospective epidemiological study by Buckner et al. Thus, it appears that protein consumption in the evening before sleep might be an underutilized time to take advantage of a protein feeding opportunity that can potentially improve body composition and performance.

In addition to direct assessments of timed administration of nutrients, other studies have explored questions that center upon the pattern of when certain protein-containing meals are consumed. Paddon-Jones et al. In this study, participants were given an EAA supplement three times a day for 28 days.

Results indicated that acute stimulation of MPS provided by the supplement on day 1 resulted in a net gain of ~7. When extrapolated over the entire day study, the predicted change in muscle mass corresponded to the actual change in muscle mass ~ g measured by dual-energy x-ray absorptiometry DEXA [ 97 ].

While these findings are important, it is vital to highlight that this study incorporated a bed rest model with no acute exercise stimulus while other work by Mitchell et al. Interestingly, supplementation with 15 g of EAAs and 30 g of carbohydrate produced a greater anabolic effect increase in net phenylalanine balance than the ingestion of a mixed macronutrient meal, despite the fact that both interventions contained a similar dose of EAAs [ 96 ].

Most importantly, the consumption of the supplement did not interfere with the normal anabolic response to the meal consumed three hours later [ 96 ].

Areta et al. The researchers compared the anabolic responses of three different patterns of ingestion a total of 80 g of protein throughout a h recovery period after resistance exercise. Using a group of healthy young adult males, the protein feeding strategies consisted of small pulsed 8 × 10 g , intermediate 4 × 20 g , or bolus 2 × 40 g administration of whey protein over the h measurement window.

Results showed that the intermediate dosing 4 × 20 g was superior for stimulating MPS for the h experimental period. Specifically, the rates of myofibrillar protein synthesis were optimized throughout the day of recovery by the consumption of 20 g protein every three hours compared to large 2 × 40 g , less frequent servings or smaller but more frequent 8 × 10 g patterns of protein intake [ 67 ].

Previously, the effect of various protein feeding strategies on skeletal MPS during an entire day was unknown. This study provided novel information demonstrating that the regulation of MPS can be modulated by the timing and distribution of protein over 12 h after a single bout of resistance exercise.

However, it should be noted that an 80 g dose of protein over a h period is quite low. The logical next step for researchers is to extend these findings into longitudinal training studies to see if these patterns can significantly affect resistance-training adaptations. Indeed, published studies by Arnal [ ] and Tinsley [ ] have all made some attempt to examine the impact of adjusting the pattern of protein consumption across the day in combination with various forms of exercise.

Collective results from these studies are mixed. Thus, future studies in young adults should be designed to compare a balanced vs. skewed distribution pattern of daily protein intake on the daytime stimulation of MPS under resting and post-exercise conditions and training-induced changes in muscle mass, while taking into consideration the established optimal dose of protein contained in a single serving for young adults.

Without more conclusive evidence spanning several weeks, it seems pragmatic to recommend the consumption of at least g of protein ~0. In the absence of feeding and in response to resistance exercise, muscle protein balance remains negative.

Skeletal muscle is sensitized to the effects of protein and amino acids for up to 24 h after completion of a bout of resistance exercise. A protein dose of 20—40 g of protein 10—12 g of EAAs, 1—3 g of leucine stimulates MPS, which can help to promote a positive nitrogen balance.

The EAAs are critically needed for achieving maximal rates of MPS making high-quality, protein sources that are rich in EAAs and leucine the preferred sources of protein. Studies have suggested that pre-exercise feedings of amino acids in combination with carbohydrate can achieve maximal rates of MPS, but protein and amino acid feedings during this time are not clearly documented to increase exercise performance.

Total protein and calorie intake appears to be the most important consideration when it comes to promoting positive adaptations to resistance training, and the impact of timing strategies immediately before or immediately after to heighten these adaptations in non-athletic populations appears to be minimal.

Proteins provide the building blocks of all tissues via their constituent amino acids. Athletes consume dietary protein to repair and rebuild skeletal muscle and connective tissues following intense training bouts or athletic events. A report in by Phillips [ ] summarized the findings surrounding protein requirements in resistance-trained athletes.

Using a regression approach, he concluded that a protein intake of 1. A key consideration regarding these recommended values is that all generated data were obtained using the nitrogen balance technique, which is known to underestimate protein requirements.

Interestingly, two of the included papers had prescribed protein intakes of 2. All data points from these two studies also had the highest levels of positive nitrogen balance.

For an athlete seeking to ensure an anabolic environment, higher daily protein intakes might be needed. Another challenge that underpins the ability to universally and successfully recommend daily protein amounts are factors related to the volume of the exercise program, age, body composition and training status of the athlete; as well as the total energy intake in the diet, particularly for athletes who desire to lose fat and are restricting calories to accomplish this goal [ ].

For these reasons, and due to an increase of published studies in areas related to optimal protein dosing, timing and composition, protein needs are being recommended within this position stand on a per meal basis.

For example, Moore [ 31 ] found that muscle and albumin protein synthesis was optimized at approximately 20 g of egg protein at rest.

Witard et al. Furthermore, while results from these studies offer indications of what optimal absolute dosing amounts may be, Phillips [ ] concluded that a relative dose of 0.

Once a total daily target protein intake has been achieved, the frequency and pattern with which optimal doses are ingested may serve as a key determinant of overall changes in protein synthetic rates.

Research indicates that rates of MPS rapidly rise to peak levels within 30 min of protein ingestion and are maintained for up to three hours before rapidly beginning to lower to basal rates of MPS even though amino acids are still elevated in the blood [ ]. Using an oral ingestion model of 48 g of whey protein in healthy young men, rates of myofibrillar protein synthesis increased three-fold within 45—90 min before slowly declining to basal rates of MPS all while plasma concentration of EAAs remained significantly elevated [ ].

While largely unexplored in a human model, these authors relied upon an animal model and were able to reinstate increases in MPS using the consumption of leucine and carbohydrate min after ingestion of the first meal. As such, it is suggested that individuals attempting to restrict caloric intake should consume three to four whole meals consisting of 20—40 g of protein per meal.

While this recommendation stems primarily from initial work that indicated protein doses of 20—40 g favorably promote increased rates of MPS [ 31 , , ], Kim and colleagues [ ] recently reported that a 70 g dose of protein promoted a more favorable net balance of protein when compared to a 40 g dose due to a stronger attenuation of rates of muscle protein breakdown.

For those attempting to increase their calories, we suggest consuming small snacks between meals consisting of both a complete protein and a carbohydrate source. This contention is supported by research from Paddon-Jones et al. These researchers compared three cal mixed macronutrient meals to three cal meals combined with three cal amino acid-carbohydrate snacks between meals.

Additionally, using a protein distribution pattern of 20—25 g doses every three hours in response to a single bout of lower body resistance exercise appears to promote the greatest increase in MPS rates and phosphorylation of key intramuscular proteins linked to muscle hypertrophy [ ].

This simple addition could provide benefits for individuals looking to increase muscle mass and improve body composition in general while also striving to maintain or improve health and performance.

The current RDA for protein is 0. While previous recommendations have suggested a daily intake of 1. Daily and per dose needs are combinations of many factors including volume of exercise, age, body composition, total energy intake and training status of the athlete.

Daily intakes of 1. Even higher amounts ~70 g appear to be necessary to promote attenuation of muscle protein breakdown. Pacing or spreading these feeding episodes approximately three hours apart has been consistently reported to promote sustained, increased levels of MPS and performance benefits.

There are 20 total amino acids, comprised of 9 EAAs and 11 non-essential amino acids NEAAs. EAAs cannot be produced in the body and therefore must be consumed in the diet.

Several methods exist to determine protein quality such as Chemical Score, Protein Efficiency Ratio, Biological Value, Protein Digestibility-Corrected Amino Acid Score PDCAAS and most recently, the Indicator Amino Acid Oxidation IAAO technique. Ultimately, in vivo protein quality is typically defined as how effective a protein is at stimulating MPS and promoting muscle hypertrophy [ ].

Overall, research has shown that products containing animal and dairy-based proteins contain the highest percentage of EAAs and result in greater hypertrophy and protein synthesis following resistance training when compared to a vegetarian protein-matched control, which typically lacks one or more EAAs [ 86 , 93 , ].

Several studies, but not all, [ ] have indicated that EAAs alone stimulate protein synthesis in the same magnitude as a whole protein with the same EAA content [ 98 ].

For example, Borsheim et al. Moreover, Paddon-Jones and colleagues [ 96 ] found that a cal supplement containing 15 g of EAAs stimulated greater rates of protein synthesis than an cal meal with the same EAA content from a whole protein source.

While important, the impact of a larger meal on changes in circulation and the subsequent delivery of the relevant amino acids to the muscle might operate as important considerations when interpreting this data.

In contrast, Katsanos and colleagues [ ] had 15 elderly subjects consume either 15 g of whey protein or individual doses of the essential and nonessential amino acids that were identical to what is found in a g whey protein dose on separate occasions.

Whey protein ingestion significantly increased leg phenylalanine balance, an index of muscle protein accrual, while EAA and NEAA ingestion exerted no significant impact on leg phenylalanine balance.

This study, and the results reported by others [ ] have led to the suggestion that an approximate 10 g dose of EAAs might serve as an optimal dose to maximally stimulate MPS and that intact protein feedings of appropriate amounts as opposed to free amino acids to elderly individuals may stimulate greater improvements in leg muscle protein accrual.

Based on this research, scientists have also attempted to determine which of the EAAs are primarily responsible for modulating protein balance. The three branched-chain amino acids BCAAs , leucine, isoleucine, and valine are unique among the EAAs for their roles in protein metabolism [ ], neural function [ , , ], and blood glucose and insulin regulation [ ].

Additionally, enzymes responsible for the degradation of BCAAs operate in a rate-limiting fashion and are found in low levels in splanchnic tissues [ ]. Thus, orally ingested BCAAs appear rapidly in the bloodstream and expose muscle to high concentrations ultimately making them key components of skeletal MPS [ ].

Furthermore, Wilson and colleagues [ ] have recently demonstrated, in an animal model, that leucine ingestion alone and with carbohydrate consumed between meals min post-consumption extends protein synthesis by increasing the energy status of the muscle fiber.

Multiple human studies have supported the contention that leucine drives protein synthesis [ , ]. Moreover, this response may occur in a dose-dependent fashion, plateauing at approximately two g at rest [ 31 , ], and increasing up to 3.

However, it is important to realize that the duration of protein synthesis after resistance exercise appears to be limited by both the signal leucine concentrations , ATP status, as well as the availability of substrate i.

As such, increasing leucine concentration may stimulate increases in muscle protein, but a higher total dose of all EAAs as free form amino acids or intact protein sources seems to be most suited for sustaining the increased rates of MPS [ ]. It is well known that exercise improves net muscle protein balance and in the absence of protein feeding, this balance becomes more negative.

When combined with protein feeding, net muscle protein balance after exercise becomes positive [ ]. Norton and Layman [ ] proposed that consumption of leucine, could turn a negative protein balance to a positive balance following an intense exercise bout by prolonging the MPS response to feeding.

In support, the ingestion of a protein or essential amino acid complex that contains sufficient amounts of leucine has been shown to shift protein balance to a net positive state after intense exercise training [ 46 , ]. Even though leucine has been demonstrated to independently stimulate protein synthesis, it is important to recognize that supplementation should not be with just leucine alone.

For instance, Wilson et al. In summary, athletes should focus on consuming adequate leucine content in each of their meals through selection of high-quality protein sources [ ]. Protein sources containing higher levels of the EAAs are considered to be higher quality sources of protein. The body uses 20 amino acids to make proteins, seven of which are essential nine conditionally , requiring their ingestion to meet daily needs.

EAAs appear to be uniquely responsible for increasing MPS with doses ranging from 6 to 15 g all exerting stimulatory effects.

In addition, doses of approximately one to three g of leucine per meal appear to be needed to stimulate protein translation machinery. The BCAAs i. However, the extent to which these changes are aligned with changes in MPS remains to be fully explored.

While greater doses of leucine have been shown to independently stimulate increases in protein synthesis, a balanced consumption of the EAAs promotes the greatest increases. Milk proteins have undergone extensive research related to their potential roles in augmenting adaptations from exercise training [ 86 , 93 ].

For example, consuming milk following exercise has been demonstrated to accelerate recovery from muscle damaging exercise [ ], increase glycogen replenishment [ ], improve hydration status [ , ], and improve protein balance to favor synthesis [ 86 , 93 ], ultimately resulting in increased gains in both neuromuscular strength and skeletal muscle hypertrophy [ 93 ].

Moreover, milk protein contains the highest score on the PDCAAS rating system, and in general contains the greatest density of leucine [ ]. Milk can be fractionated into two protein classes, casein and whey.

While both are high in quality, the two differ in the rate at which they digest as well as the impact they have on protein metabolism [ , , ]. Whey protein is water soluble, mixes easily, and is rapidly digested [ ]. In contrast, casein is water insoluble, coagulates in the gut and is digested more slowly than whey protein [ ].

Casein also has intrinsic properties such as opioid peptides, which effectively slow gastric motility [ ]. Original research investigating the effects of digestion rate was conducted by Boirie, Dangin and colleagues [ , , ]. These researchers gave a 30 g bolus of whey protein and a 43 g bolus of casein protein to subjects on separate occasions and measured amino acid levels for several hours after ingestion.

They reported that the whey protein condition displayed robust hyperaminoacidemia min after administration. However, by min, amino acid concentrations had returned to baseline. In contrast, the casein condition resulted in a slow increase in amino acid concentrations, which remained elevated above baseline after min.

Over the study duration, casein produced a greater whole body leucine balance than the whey protein condition, leading the researcher to suggest that prolonged, moderate hyperaminoacidemia is more effective at stimulating increases in whole body protein anabolism than a robust, short lasting hyperaminoacidemia.

While this research appears to support the efficacy of slower digesting proteins, subsequent work has questioned its validity in athletes. The first major criticism is that Boire and colleagues investigated whole body non-muscle and muscle protein balance instead of skeletal myofibrillar MPS.

These findings suggest that changes in whole body protein turnover may poorly reflect the level of skeletal muscle protein metabolism that may be taking place. Trommelen and investigators [ ] examined 24 young men ingesting 30 g of casein protein with or without completion of a single bout of resistance exercise, and concluded that rates of MPS were increased, but whole-body protein synthesis rates were not impacted.

More recently, Tang and colleagues [ 86 ] investigated the effects of administering 22 g of hydrolyzed whey isolate and micellar casein 10 g of EAAs at both rest and following a single bout of resistance training in young males.

Moreover, these researchers reported that whey protein ingestion stimulated greater MPS at both rest and following exercise when compared to casein. In comparison to the control group, both whey and casein significantly increased leucine balance, but no differences were found between the two protein sources for amino acid uptake and muscle protein balance.

Additional research has also demonstrated that 10 weeks of whey protein supplementation in trained bodybuilders resulted in greater gains in lean mass 5. These findings suggest that the faster-digesting whey proteins may be more beneficial for skeletal muscle adaptations than the slower digesting casein.

Skeletal muscle glycogen stores are a critical element to both prolonged and high-intensity exercise. In skeletal muscle, glycogen synthase activity is considered one of the key regulatory factors for glycogen synthesis. Research has demonstrated that the addition of protein in the form of milk and whey protein isolate 0.

Further, the addition of protein facilitates repair and recovery of the exercised muscle [ 12 ]. These effects are thought to be related to a greater insulin response following the exercise bout.

Intriguingly, it has also been demonstrated that whey protein enhances glycogen synthesis in the liver and skeletal muscle more than casein in an insulin-independent fashion that appears to be due to its capacity to upregulate glycogen synthase activity [ ]. Therefore, the addition of milk protein to a post-workout meal may augment recovery, improve protein balance, and speed glycogen replenishment.

While athletes tend to view whey as the ideal protein for skeletal muscle repair and function it also has several health benefits. In particular, whey protein contains an array of biologically active peptides whose amino acids sequences give them specific signaling effects when liberated in the gut.

Furthermore, whey protein appears to play a role in enhancing lymphatic and immune system responses [ ]. In addition, α-lactalbumin contains an ample supply of tryptophan which increases cognitive performance under stress [ ], improves the quality of sleep [ , ], and may also speed wound healing [ ], properties which could be vital for recovery from combat and contact sporting events.

In addition, lactoferrin is also found in both milk and in whey protein, and has been demonstrated to have antibacterial, antiviral, and antioxidant properties [ ].

Moreover, there is some evidence that whey protein can bind iron and therefore increase its absorption and retention [ ]. Egg protein is often thought of as an ideal protein because its amino acid profile has been used as the standard for comparing other dietary proteins [ ].

Due to their excellent digestibility and amino acid content, eggs are an excellent source of protein for athletes. While the consumption of eggs has been criticized due to their cholesterol content, a growing body of evidence demonstrates the lack of a relationship between egg consumption and coronary heart disease, making egg-based products more appealing [ ].

One large egg has 75 kcal and 6 g of protein, but only 1. Research using eggs as the protein source for athletic performance and body composition is lacking, perhaps due to less funding opportunities relative to funding for dairy.

Egg protein may be particularly important for athletes, as this protein source has been demonstrated to significantly increase protein synthesis of both skeletal muscle and plasma proteins after resistance exercise at both 20 and 40 g doses. Leucine oxidation rates were found to increase following the 40 g dose, suggesting that this amount exceeds an optimal dose [ 31 ].

In addition to providing a cost effective, high-quality source of protein rich in leucine 0. Functional foods are defined as foods that, by the presence of physiologically active components, provide a health benefit beyond basic nutrition [ ].

According to the Academy of Nutrition and Dietetics, functional foods should be consumed as part of a varied diet on a regular basis, at effective levels [ ]. Thus, it is essential that athletes select foods that meet protein requirements and also optimize health and prevent decrements in immune function following intense training.

Eggs are also rich in choline, a nutrient which may have positive effects on cognitive function [ ]. Moreover, eggs provide an excellent source of the carotenoid-based antioxidants lutein and zeaxanthin [ ].

Also, eggs can be prepared with most meal choices, whether at breakfast, lunch, or dinner. Such positive properties increase the probability of the athletes adhering to a diet rich in egg protein.

Meat proteins are a major staple in the American diet and, depending on the cut of meat, contain varying amounts of fat and cholesterol. Meat proteins are well known to be rich sources of the EAAs [ ]. Beef is a common source of dietary protein and is considered to be of high biological value because it contains the full balance of EAAs in a fraction similar to that found in human skeletal muscle [ ].

A standard serving of Moreover, this 30 g dose of beef protein has been shown to stimulate protein synthesis in both young and elderly subjects [ ]. In addition to its rich content of amino acids, beef and other flesh proteins can serve as important sources of micronutrients such as iron, selenium, vitamins A, B12 and folic acid.

This is a particularly important consideration for pregnant and breastfeeding women. Ultimately, as an essential part of a mixed diet, meat helps to ensure adequate distribution of essential micronutrients and amino acids to the body. Research has shown that significant differences in skeletal muscle mass and body composition between older men who resistance train and either consume meat-based or lactoovovegetarian diet [ ].

Over a week period, whole-body density, fat-free mass, and whole-body muscle mass as measured by urinary creatinine excretion increased in the meat-sourced diet group but decreased in the lactoovovegetarian diet group.

These results indicate that not only do meat-based diets increase fat-free mass, but also they may specifically increase muscle mass, thus supporting the many benefits of meat-based diets. A diet high in meat protein in older adults may provide an important resource in reducing the risk of sarcopenia.

Positive results have also been seen in elite athletes that consume meat-based proteins, as opposed to vegetarian diets [ ]. For example, carnitine is a molecule that transports long-chain fatty acids into mitochondria for oxidation and is found in high amounts in meat.

While evidence is lacking to support an increase in fat oxidation with increased carnitine availability, carnitine has been linked to the sparing of muscle glycogen, and decreases in exercise-induced muscle damage [ ].

Certainly, more research is needed to support these assertions. Creatine is a naturally occurring compound found mainly in muscle. Vegetarians have lower total body creatine stores than omnivores, which demonstrates that regular meat eating has a significant effect on human creatine status [ ].

Moreover, creatine supplementation studies with vegetarians indicate that increased creatine uptake levels do exist in people who practice various forms of vegetarianism [ ]. Sharp and investigators [ ] published the only study known to compare different supplemental powdered forms of animal proteins on adaptations to resistance training such as increases in strength and improvements in body composition.

Forty-one men and women performed a standardized resistance-training program over eight weeks and consumed a daily 46 g dose of either hydrolyzed chicken protein, beef protein isolate, or whey protein concentrate in comparison to a control group.

All groups experienced similar increases in upper and lower-body strength, but all protein-supplemented groups reported significant increases in lean mass and decreases in fat mass. Meat-based diets have been shown to include additional overall health benefits.

Some studies have found that meat, as a protein source, is associated with higher serum levels of IGF-1 [ ], which in turn is related to increased bone mineralization and fewer fractures [ ]. A highly debated topic in nutrition and epidemiology is whether vegetarian diets are a healthier choice than omnivorous diets.

One key difference is the fact that vegetarian diets often lack equivalent amounts of protein when compared to omnivorous diets [ ]. However, with proper supplementation and careful nutritional choices, it is possible to have complete proteins in a vegetarian diet.

Generally by consuming high-quality, animal-based products meat, milk, eggs, and cheese an individual will achieve optimal growth as compared to ingesting only plant proteins [ ]. Research has shown that soy is considered a lower quality complete protein. Hartman et al.

They found that the participants that consumed the milk protein increased lean mass and decreased fat mass more than the control and soy groups. Moreover, the soy group was not significantly different from the control group.

Similarly, a study by Tang and colleagues [ 86 ] directly compared the abilities of hydrolyzed whey isolate, soy isolate, and micellar casein to stimulate rates of MPS both at rest and in response to a single bout of lower body resistance training.

These authors reported that the ability of soy to stimulate MPS was greater than casein, but less than whey, at rest and in response to an acute resistance exercise stimulus. While soy is considered a complete protein, it contains lower amounts of BCAAs than bovine milk [ ].

Additionally, research has found that dietary soy phytoestrogens inhibit mTOR expression in skeletal muscle through activation of AMPK [ ]. Thus, not only does soy contain lower amounts of the EAAs and leucine, but soy protein may also be responsible for inhibiting growth factors and protein synthesis via its negative regulation of mTOR.

When considering the multitude of plant sources of protein, soy overwhelmingly has the most research. Limited evidence using wheat protein in older men has suggested that wheat protein stimulates significantly lower levels of MPS when compared to an identical dose 35 g of casein protein, but when this dose is increased nearly two fold 60 g this protein source is able to significantly increase rates of myofibrillar protein synthesis [ ].

As mentioned earlier, a study by Joy and colleagues [ 89 ] in which participants participated in resistance training program for eight weeks while taking identical, high doses of either rice or whey protein, demonstrated that rice protein stimulated similar increases in body composition adaptations to whey protein.

The majority of available science has explored the efficacy of ingesting single protein sources, but evidence continues to mount that combining protein sources may afford additional benefits [ ]. For example, a week resistance training study by Kerksick and colleagues [ 22 ] demonstrated that a combination of whey 40 g and casein 8 g yielded the greatest increase in fat-free mass determined by DEXA when compared to both a combination of 40 g of whey, 5 g of glutamine, and 3 g of BCAAs and a placebo consisting of 48 g of a maltodextrin carbohydrate.

Later, Kerksick et al. Similarly, Hartman and investigators [ 93 ] had 56 healthy young men train for 12 weeks while either ingesting isocaloric and isonitrogenous doses of fat-free milk a blend of whey and casein , soy protein or a carbohydrate placebo and concluded that fat-free milk stimulated the greatest increases in Type I and II muscle fiber area as well as fat-free mass; however, strength outcomes were not affected.

Moreover, Wilkinson and colleagues [ 94 ] demonstrated that ingestion of fat-free milk vs. soy or carbohydrate led to a greater area under the curve for net balance of protein and that the fractional synthesis rate of muscle protein was greatest after milk ingestion.

In , Reidy et al. However, when the entire four-hour measurement period was considered, no difference in MPS rates were found. A follow-up publication from the same clinical trial also reported that ingestion of the protein blend resulted in a positive and prolonged amino acid balance when compared to ingestion of whey protein alone, while post-exercise rates of myofibrillar protein synthesis were similar between the two conditions [ ].

Reidy et al. No differences were found between whey and the whey and soy blend. Some valid criteria exist to compare protein sources and provide an objective method of how to include them in a diet. As previously mentioned, common means of assessing protein quality include Biological Value, Protein Efficiency Ratio, PDCAAS and IAAO.

The derivation of each technique is different with all having distinct advantages and disadvantages. For nearly all populations, ideal methods should be linked to the capacity of the protein to positively affect protein balance in the short term, and facilitate increases and decreases in lean and fat-mass, respectively, over the long term.

To this point, dairy, egg, meat, and plant-based proteins have been discussed. As mentioned previously, initial research by Boirie and Dangin has highlighted the impact of protein digestion rate on net protein balance with the two milk proteins: whey and casein [ , , ].

Subsequent follow-up work has used this premise as a reference point for the digestion rates of other protein sources. Using the criteria of leucine content, Norton and Wilson et al. Wheat and soy did not stimulate MPS above fasted levels, whereas egg and whey proteins significantly increased MPS rates, with MPS for whey protein being greater than egg protein.

MPS responses were closely related to changes in plasma leucine and phosphorylation of 4E—BP1 and S6 K protein signaling molecules. More importantly, following 2- and weeks of ingestion, it was demonstrated that the leucine content of the meals increased muscle mass and was inversely correlated with body fat.

Tang et al. These findings lead us to conclude that athletes should seek protein sources that are both fast-digesting and high in leucine content to maximally stimulate rates of MPS at rest and following training. Moreover, in consideration of the various additional attributes that high-quality protein sources deliver, it may be advantageous to consume a combination of higher quality protein sources dairy, egg, and meat sources.

Multiple protein sources are available for an athlete to consider, and each has their own advantages and disadvantages. Protein sources are commonly evaluated based upon the content of amino acids, particularly the EAAs, they provide. Blends of protein sources might afford a favorable combination of key nutrients such as leucine, EAAs, bioactive peptides, and antioxidants, but more research is needed to determine their ideal composition.

Nutrient density is defined as the amount of a particular nutrient carbohydrate, protein, fat, etc. per unit of energy in a given food. In many situations, the commercial preparation method of foods can affect the actual nutrient density of the resulting food.

When producing milk protein supplements, special preparations must be made to separate the protein sources from the lactose and fat calories in milk. For example, the addition of acid to milk causes the casein to coagulate or collect at the bottom, while the whey is left on the top [ ].

These proteins are then filtered to increase their purity. Filtration methods differ, and there are both benefits and disadvantages to each. Ion exchange exposes a given protein source, such as whey, to hydrochloric acid and sodium hydroxide, thereby producing an electric charge on the proteins that can be used to separate them from lactose and fat [ ].

The advantage of this method is that it is relatively cheap and produces the highest protein concentration [ ]. The disadvantage is that ion exchange filtration typically denatures some of the valuable immune-boosting, anti-carcinogenic peptides found in whey [ ].

Cross-flow microfiltration, and ultra-micro filtration are based on the premise that the molecular weight of whey protein is greater than lactose, and use 1 and 0. As a result, whey protein is trapped in the membranes but the lactose and other components pass through.

The advantage is that these processes do not denature valuable proteins and peptides found in whey, so the protein itself is deemed to be of higher quality [ ].

The main disadvantage is that this filtration process is typically costlier than the ion exchange method. When consumed whole, proteins are digested through a series of steps beginning with homogenization by chewing, followed by partial digestion by pepsin in the stomach [ ].

Following this, a combination of peptides, proteins, and negligible amounts of single amino acids are released into the small intestine and from there are either partially hydrolyzed into oligopeptides, 2—8 amino acids in length or are fully hydrolyzed into individual amino acids [ ].

Absorption of individual amino acids and various small peptides di, tri, and tetra into the blood occurs inside the small intestine through separate transport mechanisms [ ].

Oftentimes, products contain proteins that have been pre-exposed to specific digestive enzymes causing hydrolysis of the proteins into di, tri, and tetrapeptides. A plethora of studies have investigated the effects of the degree of protein fractionation or degree of hydrolysis on the absorption of amino acids and the subsequent hormonal response [ , , , , , ].

Further, the rate of absorption may lead to a more favorable anabolic hormonal environment [ , , ]. Calbet et al. Each of the nitrogen containing solutions contained 15 g of glucose and 30 g of protein. Results indicated that peptide hydrolysates produced a faster increase in venous plasma amino acids compared to milk proteins.

Further, the peptide hydrolysates produced peak plasma insulin levels that were two- and four-times greater than that evoked by the milk and glucose solutions, respectively, with a correlation of 0. In a more appropriate comparison, Morifuji et al.

However, Calbet et al. The hydrolyzed casein, however, did result in a greater amino acid response than the nonhydrolyzed casein. Finally, both hydrolyzed groups resulted in greater gastric secretions, as well as greater plasma increases, in glucose-dependent insulinotropic polypeptides [ ].

Buckley and colleagues [ ] found that a ~ 30 g dose of a hydrolyzed whey protein isolate resulted in a more rapid recovery of muscle force-generating capacity following eccentric exercise, compared with a flavored water placebo or a non-hydrolyzed form of the same whey protein isolate. In agreement with these findings, Cooke et al.

Three and seven days after completing the damaging exercise bout, maximal strength levels were higher in the hydrolyzed whey protein group compared to carbohydrate supplementation. Additionally, blood concentrations of muscle damage markers tended to be lower when four ~g doses of a hydrolyzed whey protein isolate were ingested for two weeks following the damaging bout.

Beyond influencing strength recovery after damaging exercise, other benefits of hydrolyzed proteins have been suggested. For example, Morifuji et al. Furthermore, Lockwood et al. Results indicated that strength and lean body mass LBM increased equally in all groups. However, fat mass decreased only in the hydrolyzed whey protein group.

While more work needs to be completed to fully determine the potential impact of hydrolyzed proteins on strength and body composition changes, this initial study suggests that hydrolyzed whey may be efficacious for decreasing body fat.

Finally, Saunders et al. The authors reported that co-ingestion of a carbohydrate and protein hydrolysate improved time-trial performance late in the exercise protocol and significantly reduced soreness and markers of muscle damage. Two excellent reviews on the topic of hydrolyzed proteins and their impact on performance and recovery have been published by Van Loon et al.

The prevalence of digestive enzymes in sports nutrition products has increased during recent years with many products now containing a combination of proteases and lipases, with the addition of carbohydrates in plant proteins.

Proteases can hydrolyze proteins into various peptide configurations and potentially single amino acids. It appears that digestive enzyme capabilities and production decrease with age [ ], thus increasing the difficulty with which the body can break down and digest large meals.

Digestive enzymes could potentially work to promote optimal digestion by allowing up-regulation of various metabolic enzymes that may be needed to allow for efficient bodily operation. Further, digestive enzymes have been shown to minimize quality differences between varying protein sources [ ].

Individuals looking to increase plasma peak amino acid concentrations may benefit from hydrolyzed protein sources or protein supplemented with digestive enzymes. However, more work is needed before definitive conclusions can be drawn regarding the efficacy of digestive enzymes.

Despite a plethora of studies demonstrating safety, much concern still exists surrounding the clinical implications of consuming increased amounts of protein, particularly on renal and hepatic health. The majority of these concerns stem from renal failure patients and educational dogma that has not been rewritten as evidence mounts to the contrary.

Certainly, it is clear that people in renal failure benefit from protein-restricted diets [ ], but extending this pathophysiology to otherwise healthy exercise-trained individuals who are not clinically compromised is inappropriate.

Published reviews on this topic consistently report that an increased intake of protein by competitive athletes and active individuals provides no indication of hepato-renal harm or damage [ , ].

This is supported by a recent commentary [ ] which referenced recent reports from the World Health Organization [ ] where they indicated a lack of evidence linking a high protein diet to renal disease. Likewise, the panel charged with establishing reference nutrient values for Australia and New Zealand also stated there was no published evidence that elevated intakes of protein exerted any negative impact on kidney function in athletes or in general [ ].

Recently, Antonio and colleagues published a series of original investigations that prescribed extremely high amounts of protein ~3. The first study in had resistance-trained individuals consume an extremely high protein diet 4. A follow-up investigation [ ] required participants to ingest up to 3.

Their next study employed a crossover study design in twelve healthy resistance-trained men in which each participant was tested before and after for body composition as well as blood-markers of health and performance [ ].

In one eight-week block, participants followed their normal habitual diet 2. No changes in body composition were reported, and importantly, no clinical side effects were observed throughout the study.

Finally, the same group of authors published a one-year crossover study [ ] in fourteen healthy resistance-trained men. This investigation showed that the chronic consumption of a high protein diet i. Furthermore, there were no alterations in clinical markers of metabolism and blood lipids.

Multiple review articles indicate that no controlled scientific evidence exists indicating that increased intakes of protein pose any health risks in healthy, exercising individuals. A series of controlled investigations spanning up to one year in duration utilizing protein intakes of up to 2.

In alignment with our previous position stand, it is the position of the International Society of Sports Nutrition that the majority of exercising individuals should consume at minimum approximately 1. The amount is dependent upon the mode and intensity of the exercise, the quality of the protein ingested, as well as the energy and carbohydrate status of the individual.

Concerns that protein intake within this range is unhealthy are unfounded in healthy, exercising individuals. An attempt should be made to consume whole foods that contain high-quality e. The timing of protein intake in the period encompassing the exercise session may offer several benefits including improved recovery and greater gains in lean body mass.

In addition, consuming protein pre-sleep has been shown to increase overnight MPS and next-morning metabolism acutely along with improvements in muscle size and strength over 12 weeks of resistance training. Intact protein supplements, EAAs and leucine have been shown to be beneficial for the exercising individual by increasing the rates of MPS, decreasing muscle protein degradation, and possibly aiding in recovery from exercise.

In summary, increasing protein intake using whole foods as well as high-quality supplemental protein sources can improve the adaptive response to training. Campbell B, Kreider RB, Ziegenfuss T, La Bounty P, Roberts M, Burke D, et al.

International society of sports nutrition position stand: protein and exercise. J Int Soc Sports Nutr. Macdermid PW, Stannard SR. A whey-supplemented, high-protein diet versus a high-carbohydrate diet: effects on endurance cycling performance.

Int J Sport Nutr Exerc Metab. Article CAS PubMed Google Scholar. Burke LM, Hawley JA, Wong SH, Jeukendrup AE. Carbohydrates for training and competition. J Sports Sci. Article PubMed Google Scholar. Witard OC, Jackman SR, Kies AK, Jeukendrup AE, Tipton KD.

Effect of increased dietary protein on tolerance to intensified training. Med Sci Sports Exerc. D'lugos AC, Luden ND, Faller JM, Akers JD, Mckenzie AI, Saunders MJ.

Supplemental protein during heavy cycling training and recovery impacts skeletal muscle and heart rate responses but not performance.

Article CAS Google Scholar. Breen L, Tipton KD, Jeukendrup AE. No effect of carbohydrate-protein on cycling performance and indices of recovery.

CAS PubMed Google Scholar. Saunders MJ, Moore RW, Kies AK, Luden ND, Pratt CA. Carbohydrate and protein hydrolysate coingestions improvement of late-exercise time-trial performance.

Valentine RJ, Saunders MJ, Todd MK, St Laurent TG. Influence of carbohydrate-protein beverage on cycling endurance and indices of muscle disruption. Van Essen M, Gibala MJ. Failure of protein to improve time trial performance when added to a sports drink.

Article PubMed CAS Google Scholar. Ivy JL, Res PT, Sprague RC, Widzer MO. Effect of a carbohydrate-protein supplement on endurance performance during exercise of varying intensity.

Saunders MJ, Kane MD, Todd MK. Effects of a carbohydrate-protein beverage on cycling endurance and muscle damage. Saunders MJ, Luden ND, Herrick JE. Consumption of an oral carbohydrate-protein gel improves cycling endurance and prevents postexercise muscle damage.

J Strength Cond Res. PubMed Google Scholar. Romano-Ely BC, Todd MK, Saunders MJ, Laurent TS. Effect of an isocaloric carbohydrate-protein-antioxidant drink on cycling performance. Beelen M, Zorenc A, Pennings B, Senden JM, Kuipers H, Van Loon LJ. Impact of protein coingestion on muscle protein synthesis during continuous endurance type exercise.

Am J Physiol Endocrinol Metab. Andersen LL, Tufekovic G, Zebis MK, Crameri RM, Verlaan G, Kjaer M, et al. The effect of resistance training combined with timed ingestion of protein on muscle fiber size and muscle strength. Metab Clin Exp. Bemben MG, Witten MS, Carter JM, Eliot KA, Knehans AW, Bemben DA.

The effects of supplementation with creatine and protein on muscle strength following a traditional resistance training program in middle-aged and older men.

J Nutr Health Aging. Burke DG, Chilibeck PD, Davidson KS, Candow DG, Farthing J, Smith-Palmer T. The effect of whey protein supplementation with and without creatine monohydrate combined with resistance training on lean tissue mass and muscle strength.

Denysschen CA, Burton HW, Horvath PJ, Leddy JJ, Browne RW. Resistance training with soy vs whey protein supplements in hyperlipidemic males. Article PubMed PubMed Central CAS Google Scholar.

Erskine RM, Fletcher G, Hanson B, Folland JP. Whey protein does not enhance the adaptations to elbow flexor resistance training. Herda AA, Herda TJ, Costa PB, Ryan ED, Stout JR, Cramer JT. Muscle performance, size, and safety responses after eight weeks of resistance training and protein supplementation: a randomized, double-blinded, placebo-controlled clinical trial.

Hulmi JJ, Kovanen V, Selanne H, Kraemer WJ, Hakkinen K, Mero AA. Acute and long-term effects of resistance exercise with or without protein ingestion on muscle hypertrophy and gene expression.

Amino Acids. Kerksick CM, Rasmussen CJ, Lancaster SL, Magu B, Smith P, Melton C, et al. The effects of protein and amino acid supplementation on performance and training adaptations during ten weeks of resistance training. Kukuljan S, Nowson CA, Sanders K, Daly RM.

Effects of resistance exercise and fortified milk on skeletal muscle mass, muscle size, and functional performance in middle-aged and older men: an mo randomized controlled trial.

J Appl Physiol Bethesda, Md : Weisgarber KD, Candow DG, Vogt ES. Whey protein before and during resistance exercise has no effect on muscle mass and strength in untrained young adults. Willoughby DS, Stout JR, Wilborn CD.

Effects of resistance training and protein plus amino acid supplementation on muscle anabolism, mass, and strength. Candow DG, Burke NC, Smith-Palmer T, Burke DG. Effect of whey and soy protein supplementation combined with resistance training in young adults. Cribb PJ, Williams AD, Stathis CG, Carey MF, Hayes A.

Effects of whey isolate, creatine, and resistance training on muscle hypertrophy. Hoffman JR, Ratamess NA, Kang J, Falvo MJ, Faigenbaum AD. Article PubMed PubMed Central Google Scholar. Effects of protein supplementation on muscular performance and resting hormonal changes in college football players.

J Sports Sci Med. PubMed PubMed Central Google Scholar. Hida A, Hasegawa Y, Mekata Y, Usuda M, Masuda Y, Kawano H, et al. Effects of egg white protein supplementation on muscle strength and serum free amino acid concentrations. Moore DR, Robinson MJ, Fry JL, Tang JE, Glover EI, Wilkinson SB, et al.

Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men.

Am J Clin Nutr. Schoenfeld BJ, Aragon AA, Krieger JW. The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. Josse AR, Tang JE, Tarnopolsky MA, Phillips SM.

Body composition and strength changes in women with milk and resistance exercise. Taylor LW, Wilborn C, Roberts MD, White A, Dugan K. Eight weeks of pre- and postexercise whey protein supplementation increases lean body mass and improves performance in division III collegiate female basketball players.

Appl Physiol Nutr Metab. Cermak NM, Res PT, De Groot LC, Saris WH, Van Loon LJ. Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis.

Pasiakos SM, Mclellan TM, Lieberman HR. The effects of protein supplements on muscle mass, strength, and aerobic and anaerobic power in healthy adults: a systematic review. Sports Med. Rennie MJ. Control of muscle protein synthesis as a result of contractile activity and amino acid availability: implications for protein requirements.

Phillips SM. The science of muscle hypertrophy: making dietary protein count. Proc Nutr Soc. Tipton KD, Phillips SM. Dietary protein for muscle hypertrophy. Nestle Nutrition Institute workshop series.

Layman DK, Evans E, Baum JI, Seyler J, Erickson DJ, Boileau RA. Dietary protein and exercise have additive effects on body composition during weight loss in adult women.

J Nutr. Layman DK, Boileau RA, Erickson DJ, Painter JE, Shiue H, Sather C, et al. A reduced ratio of dietary carbohydrate to protein improves body composition and blood lipid profiles during weight loss in adult women. Pasiakos SM, Cao JJ, Margolis LM, Sauter ER, Whigham LD, Mcclung JP, et al.

But do anx supplements live up to the hype, and are suppleementation even necessary—or in some cases, safe? Herbal health supplements other Vegetarian detox diets supplements presergation the U. Here we review the scientific evidence behind some of the most popular ingredients in workout supplements. Pre-workout supplements are designed to provide energy and aid endurance throughout a workout. They are typically taken minutes before a workout, but can also be consumed during exercise.

Author: Gushura

4 thoughts on “Muscle preservation and proper supplementation

  1. Im Vertrauen gesagt ist meiner Meinung danach offenbar. Ich empfehle Ihnen, in google.com zu suchen

  2. Absolut ist mit Ihnen einverstanden. Darin ist etwas auch die Idee gut, ist mit Ihnen einverstanden.

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