Strategies To Optimize Muscle Growth Via Training And Diet

Combining sports nutrition and training for maximum benefit

The ultimate goal of any bodybuilder is of course to increase muscle mass. Trouble is, once you’ve passed the ‘newbie gains’ stage the rate of muscle growth begins to decline, making it increasingly difficult to maintain consistent progress. To help you stay on track, we thought we would share a recent report with you which identifies some important factors in the muscle building process.

It is a well-known fact that combining resistance training with the correct diet enhances muscle protein synthesis (MPS) and that muscle protein breakdown (MPB) acts as a counter to this process. Net protein balance (protein synthesis minus breakdown) determines the extent to which muscle mass is gained, maintained or lost over time.

Previous research has shown that a variety of factors influence MPS, including the provision of essential amino acids (1,2), the consumption of different types of protein powder (3,4,5), and the timing of nutrient ingestion (6,7).

The recent report reviews the research that has been conducted to date to help determine the patterns of nutrient ingestion and training that can deliver optimal muscle growth.

Weight training and the anabolic window

It is a maxim of bodybuilding literature that the best time to provide nutrients to the body is after a bout of weight training. Weight training itself can elevate protein synthesis for up to 48 hours (8), while the body’s response to ingesting amino acids lasts for just a few hours before MPS returns to baseline level (9,10).

Combining weight training with amino acid consumption optimises the rate of MPS (11,12), hence the common practice of drinking a protein shake immediately after training to help fuel muscle recovery and growth.

While providing your body with nutrients immediately after your workout is likely to maximise your anabolic response, this does not mean that you shouldn't continue to nourish your muscles in the hours that follow. In order to maximise muscle growth, athletes should make the most of heightened MPS activity during the 48-hour period following weight training by providing the body with a steady stream of amino acids.

Training load and volume

Several studies demonstrate a link between muscle building, muscle damage (13) and training volume (14). High-volume resistance exercise and training to failure offer the best solutions for those looking to optimise muscle growth in the short term. Those looking to build muscle mass over time should therefore employ a strategic long-term approach to progressive overload.

Supplementing with protein post workout

While any protein product can boost muscle protein synthesis to some degree, research suggests that whey and casein (both milk proteins) are optimal with greater amounts of branched chain amino acids being one reason for their superiority.

Studies comparing the effects of various protein sources on muscle protein synthesis in young (15) and old (16) individuals show that whey protein isolate enhances leucine levels (see Essential Amino Acids, below), anabolic signalling (levels of key proteins such as mTOR) and MPS to a greater extent than micellar casein, making it ideal for use post workout.

Casein, on the other hand, allows for a more sustained release of amino acids, making it the better choice of protein before bedtime (17).

Essential amino acids

Essential amino acids, particularly leucine (18), are important mediators of muscle protein synthesis and it is likely that the anabolic effect of whey protein is largely down to its high BCAA content. Research shows that BCAAs (branched chain amino acids, i.e. leucine, isoleucine and valine) can help increase muscle building even in the presence of already-high protein levels (19).

Research conducted by Layne Norton suggests that MPS is elevated for just two hours after eating, even where amino acid levels have been supplemented. Norton proposes that those looking to build muscle supplement with BCAAs between meals to maintain consistent levels of protein synthesis throughout the day.

Additionally, bypassing the digestive processes that a full meal would undergo ensures a faster uptake of amino acids, increasing MPS efficiency.

The role of carbohydrates and fats

Many athletes get so caught up in the task of optimising their protein and amino acid intake that they forget the vital role that carbohydrates and fats have to play in muscle building. As we have discussed previously in our article on post-workout nutrition, carbohydrate consumption helps raise levels of insulin, in turn inhibiting the breakdown of muscle tissue.

By reducing protein breakdown and replenishing glycogen levels, carbohydrates play a vital part in the muscle building process, boosting net protein balance and providing energy.

There is relatively little research into the role of fats in MPS, although one interesting study suggests that whole milk provides a greater boost to protein synthesis after exercise than does fat free milk (20).

Recommendations

• There are many different factors that can affect the rate of muscle growth.
• Top up on rapid-release protein after training and slow-release protein at night to optimise your body’s anabolic response.
• Consume EAA or BCAA supplements between meals to further promote muscle growth.
• According to the research conducted to date, 8-10 grams of essential amino acids is optimal for stimulating MPS, an amount that can be obtained via whole protein and/or supplemental sources.

References

1. Cuthbertson D, Smith K, Babraj J, Leese G, Waddell T, Atherton P, Wackerhage H, Taylor PM, Rennie MJ: Anabolic signaling deficits underlie amino acid resistance of wasting, aging muscle. The FASEB journal: official publication of the Federation of American Societies for Experimental Biology 2005, 19:422–424.

2. Moore DR, Robinson MJ, Fry JL, Tang JE, Glover EI, Wilkinson SB, Prior T, Tarnopolsky MA, Phillips SM: Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. Am J Clin Nutr 2009, 89:161–168.

3. Pennings B, Boirie Y, Senden JM, Gijsen AP, Kuipers H, van Loon LJ: Whey protein stimulates postprandial muscle protein accretion more effectively than do casein and casein hydrolysate in older men. Am J Clin Nutr 2011, 93:997–1005.

4. 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 soyprotein beverage. Am J Clin Nutr 2007, 85:1031–1040.

5. 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 Appl Physiol 2009, 107:987–992

6. Hartman JW, Tang JE, Wilkinson SB, Tarnopolsky MA, Lawrence RL, Fullerton AV, Phillips SM: 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. Am J Clin Nutr 2007, 86:373–381.

7. Tipton KD, Rasmussen BB, Miller SL, Wolf SE, Owens-Stovall SK, Petrini BE, Wolfe RR: Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise. Am J Physiol Endocrinol Metab 2001, 281:E197–E206.

8. Phillips SM, Tipton KD, Aarsland A, Wolf SE, Wolfe RR: Mixed muscle protein synthesis and breakdown after resistance exercise in humans. Am J Physiol 1997, 273:E99–E107.

9. Moore DR, Tang JE, Burd NA, Rerecich T, Tarnopolsky MA, Phillips SM: Differential stimulation of myofibrillar and sarcoplasmic protein synthesis with protein ingestion at rest and after resistance exercise. J Physiol 2009, 587:897–904.

10. Atherton PJ, Etheridge T, Watt PW, Wilkinson D, Selby A, Rankin D, Smith K, Rennie MJ: Muscle full effect after oral protein: time-dependent concordance and discordance between human muscle protein synthesis and mTORC1 signaling. Am J Clin Nutr 2010, 92:1080–1088.

11. 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 Physiol 1997, 273:E122–E129.

12. Moore DR, Robinson MJ, Fry JL, Tang JE, Glover EI, Wilkinson SB, Prior T, Tarnopolsky MA, Phillips SM: Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. Am J Clin Nutr 2009, 89:161–168.

13. Schoenfeld B. (2012): Does exercise induced muscle damage play a role in skeletal muscle hypertrophy

14. Burd NA, West DW, Staples AW, Atherton PJ, Baker JM, Moore DR, Holwerda AM, Parise G, Rennie MJ, Baker SK, Phillips SM: Low-load high volume resistance exercise stimulates muscle protein synthesis more than high-load low volume resistance exercise in young men. PLoS One 2010, 5:e12033.

15. 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 Appl Physiol 2009, 107:987–992.

16. 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.

17. Res PT, Groen B, Pennings B, Beelen M, Wallis GA, Gijsen AP, Senden JM, van Loon LJ. Protein Ingestion Prior To Sleep Improves Post-Exercise Overnight Recovery.Med Sci Sports Exerc. 2012 Feb 9

18. Koopman R, Wagenmakers A, Manders R, Zorenc A, Senden J, Gorselink M, Keizer H, van Loon L (2004) Combined ingestion of protein and free leucine with carbohydrate increases postexercise muscle protein synthesis in vivo in male subjects. American Journal of Physiology: Encocrinology and Metabolism. Apr; 288 (4) E645-E653

19. Effects of supplemental proteins on body composition and muscular strength in healthy athletic adult males Colker et.al (2000) 20. Elliot TA, Cree MG, Sanford AP, Wolfe RR, Tipton KD: Milk ingestion stimulates net muscle protein synthesis following resistance exercise. Medicine and science in sports and exercise 2006, 38:667–674.