Strength Nutrition: Maximizing Your Anabolic Potential : Strength & Conditioning Journal

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Strength Nutrition: Maximizing Your Anabolic Potential

Bird, Stephen PhD, CSCS

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Strength and Conditioning Journal 32(4):p 80-86, August 2010. | DOI: 10.1519/SSC.0b013e3181d5284e
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The practical application of strength nutrition concepts (28), including liquid carbohydrate (CHO), protein (PRO), both whole foods (milk) and specific PRO fractions (whey and casein), amino acid constituents (essential amino acids [EAA] and branch chain amino acids [BCAA]), and mixed nutrient ingestion (CHO/PRO), has gained popularity. However, an expansive review by Hawley et al. (14), titled Innovations in athletic preparation: Role of substrate availability to modify training adaptation and performance, highlights the central question related to strength nutrition. That is, whether acute transient changes in skeletal muscle PRO turnover induced by nutrient manipulation after a single bout of resistance exercise translates into greater gains in lean mass, muscle hypertrophy, and/or exercise performance after chronic training. In an attempt to address this central question, a modified version of the “Pathway of Adaptation Model,” previously described by Volek (29), is presented. This model provides a framework for fundamental steps that mediate acute responses to resistance exercise associated with strength nutrition and chronic muscular adaptations to training.


The Pathway of Adaptation Model describes strength nutrition concepts that mediate acute responses to resistance exercise and the chronic adaptations to training (29). However, 4 factors require consideration when determining the effectiveness of strength nutrition (Figure 1). The factors being

Figure 1:
Key factors influencing strength nutrition.
  1. Exercise programming: what type, intensity, and duration?
  2. Nutrient quantity: how much should be consumed?
  3. Nutrient quality: what kind of nutrients should be consumed?
  4. Nutrient timing: when should nutrient intake occur?

These factors are central to the Pathway of Adaptation Model and influence the sequence of events responsible for exercise-induced muscle growth and increased strength expression after nutrient ingestion. The interactions of 4 key steps in the acute response appear to be critical because this represents the “anabolic window” where strength nutrition maximizes an athlete's anabolic potential (Figure 2). There is growing evidence (3,4,8,22,26) suggesting a link between strength nutrition key nutrients (CHO and PRO/AA) and the Pathway of Adaptation Model after resistance exercise. While much of the research has centered on pre- and/or postexercise ingestion (8,13,27), ingestion during the exercise bout (2,3) is an important consideration for strength and power athletes because this represents a specific period where nutrient status becomes compromised because of training in the fasted state.

Figure 2:
Key components of the Pathway of Adaptation Model play an interactive role in mediating the acute response to resistance exercise and chronic muscular adaptation to training.


Liquid CHO ingestion during and/or after resistance exercise has been examined based on 3 primary outcomes, these being: (a) glycogen resynthesis, (b) hormonal modification, and (c) net muscle PRO balance. First, liquid CHO ingestion before exercise may reduce muscle and liver glycogen loss associated with an acute bout of resistance exercise, and this may be of importance for athletes involved in multiple training bouts per day (13). Second, liquid CHO ingestion during the exercise bout may shift the exercise-induced hormonal milieu toward a profile more favorable for anabolism (26). Specifically, it is the response of insulin and cortisol that has received much attention (2) because these hormones have major regulatory roles in CHO metabolism and PRO turnover. The CHO concentration appears to be an important regulator of the rate of gastric emptying. For example, a 20% CHO solution is reported to be significantly slower than a 6% CHO solution (20), and this will affect the acute hormonal response. Finally, CHO ingestion after exercise has been reported to improve net muscle PRO balance after resistance exercise (5). However, such an effect is considered minor when compared with the effect of AA ingestion (6) or combined CHO/AA ingestion (4). Therefore, liquid CHO ingestion in the form of a 6-8% CHO solution before exercise and/or during the exercise bout may enhance anabolic potential and exercise performance. Ingesting the CHO in liquid form may reduce the gastric emptying difficulty associated with whole foods, as well as providing a more convenient and practical alternative to whole-food ingestion.


Protein/amino acid ingestion before and/or after resistance exercise has an additive effect on muscle protein synthesis (MPS) (7,27), with small amounts (approximately 6 g) of amino acids, particularly BCAA (leucine, isoleucine, and valine) suggested to exert anticatabolic effects by not only promoting MPS (19) but also inhibiting intracellular proteolytic pathways (17). The anabolic/anticatabolic properties of BCAA initiate enzymatic activity responsible for switching on the molecular machinery responsible for MPS and muscle protein breakdown (MPB). Of the BCAAs, leucine seems to be the most potent (17) in modifying the expression of target genes at the level of transcription, messenger RNA stability, and translation, and this involves the integration input from multiple upstream pathways (10,11). From an anabolic perspective, recent reports (9,10,12) suggest that the signaling network controlling MPS is mammalian target of rapamycin (mTOR), an enzyme protein that act as a part of signaling pathway within a cell responsible for sequential activation of further signals activating MPS (i.e., telling cells to grow). Data by Dreyer et al. (9) suggests that acute increase in AA availability (particularly leucine) within the muscle, rather than insulin, is the major regulator of MPS. Specifically, leucine-enriched CHO/EAA ingestion after resistance exercise enhanced mTOR signaling with MPS increased by 145% above baseline, whereas an increase of only 41% was measured in subjects who performed the exercise without nutrition.

Conversely, the proteolytic system responsive to catabolic stimuli and MPB is the ubiquitin-proteasome pathway (18,21) (i.e., tagging muscle proteins to breakdown). Leucine ingestion specifically may impact the components of both these signaling networks. Therefore, the interplay between PRO and AA ingestion on PRO kinetics (MPS and MPB) after resistance exercise is suggested to be a major determinant for the hypertrophic response of skeletal muscle (1), resulting in greater gains in both muscle mass and strength expression.

Koopman et al. (15) further highlight the importance of PRO/AA ingestion during the postexercise recovery period. The authors outline 2 crucial points, regarding PRO/AA ingestion. First, ingestion of PRO/AA during the postexercise recovery period is necessary for hypertrophy to occur; second, athletes need to ingest PRO/AA to attain positive PRO balance and maximize the muscle adaptive response. The type and timing of PRO/AA ingestion significantly affect both muscle growth and exercise performance. Therefore, provision of these nutrients immediately before, during, and after strength exercise is critical to the net PRO response in muscle (1).


Of the macronutrients, fat, in particular, has been shown to beneficially or adversely affect testosterone response. Research indicates that consuming a low-fat diet and replacing saturated fat with polyunsaturated fat decreases basal testosterone levels (24,30). Volek et al. (30) report significant positive correlations between testosterone and fat intake (percent of energy consumption) in young strength-trained men. Furthermore, Sallinen et al. (24) suggest that diets with insufficient fat compromise the anabolic hormonal profile. Therefore, a moderate level of fat intake (20-30% of daily caloric intake) is recommended for strength athletes (16,25), with the majority of dietary fat obtained through monounsaturated (10-15% of daily caloric intake) and polyunsaturated (10-15% of daily caloric intake) fats, with small amounts of saturated fat (<10%) (25).


Strength nutrition describes nutritional supplementation strategies centered around exercise aimed at promoting muscular adaptations to resistance training by shifting the anabolic/catabolic profile toward a profile more favorable for muscle growth (3,8), with nutrient ingestion suggested to be essential for hypertrophy to occur (15). Nutrient quantity, nutrient quality, and nutrient timing are key strength nutrition concepts that impact upon the effectiveness of nutritional supplementation strategies to enhance training responses for strength and power athletes through the Pathway of Adaptation Model. Preexercise ingestion of a fast-acting PRO (whey), CHO/EAA consumption during the exercise bout, and postworkout ingestion of a combined PRO blend (whey/casein) will promote an anabolic environment aimed at optimizing exercise-induced skeletal muscle growth. Whole-food ingestion 30 minutes after workout at a ratio of 1 g/kg CHO to 0.5 g/kg PRO is recommended, with a high-CHO meal within 2 hours after completing the workout (23). Therefore, strength nutrition may be the most important component of a strength and power athlete's training process, allowing the athlete to maximize anabolic potential.


  1. The magnitude and duration of changes in nutrient status determine the anabolic effects on skeletal muscle.
  2. Ingestion of BCAAs (leucine, in particular) produces an acute response on both MPS and MPB.
  3. Mixed nutrient ingestion (CHO/PRO) is pivotal in enhancing hormonal responses and enhancing muscular performance.
  4. Strength nutrition strategies centered on preexercise, during the exercise bout and postexercise period ensure that you are providing the essential nutrients required to optimize the training response.


1. Bird SP. Protein/amino acid supplementation and resistance training: A research update. J Aust Strength Cond 17: 25-28, 2009.
2. Bird SP, Tarpenning KM, and Marino FE. Effects of liquid carbohydrate/essential amino acid ingestion on acute hormonal response during a single bout of resistance exercise in untrained men. Nutrition 22: 367-375, 2006.
3. Bird SP, Tarpenning KM, and Marino FE. Independent and combined effects of liquid carbohydrate/essential amino acid ingestion on hormonal and muscular adaptations following resistance training in untrained men. Eur J Appl Physiol 97: 225-238, 2006.
4. Borsheim E, Aarsland A, and Wolfe RR. Effect of an amino acid, protein, and carbohydrate mixture on net muscle protein balance after resistance exercise. Int J Sport Nutr Exerc Metabol 14: 255-271, 2004.
5. Borsheim E, Cree MG, Tipton KD, Elliott TA, Aarsland A, and Wolfe RR. Effect of carbohydrate intake on net muscle protein synthesis during recovery from resistance exercise. J Appl Physiol 96: 674-678, 2004.
6. Borsheim E, Tipton KD, Wolf SE, and Wolfe RR. Essential amino acids and muscle protein recovery from resistance exercise. Am J Physiol Endocrinol Metabol 283: E648-E657, 2002.
7. Cribb PJ and Hayes A. Effects of supplement timing and resistance exercise on skeletal muscle hypertrophy. Med Sci Sports Exerc 38: 1918-1925, 2006.
8. Cribb PJ, Williams AD, Stathis CG, Carey MF, and Hayes A. Effects of whey isolate, creatine, and resistance training on muscle hypertrophy. Med Sci Sports Exerc 39: 298-307, 2007.
9. Dreyer HC, Drummond MJ, Pennings B, Fujita S, Glynn EL, Chinkes DL, Dhanani S, Volpi E, and Rasmussen BB. Leucine-enriched essential amino acid and carbohydrate ingestion following resistance exercise enhances mTOR signaling and protein synthesis in human muscle. Am J Physiol Endocrinol Metab 294: E392-E400, 2008.
10. Drummond MJ and Rasmussen BB. Leucine-enriched nutrients and the regulation of mammalian target of rapamycin signalling and human skeletal muscle protein synthesis. Curr Opin Clin Nutr Metab Care 11: 222-226, 2008.
11. Fingar DC and Blenis J. Target of rapamycin (TOR): An integrator of nutrient and growth factor signals and coordinator of cell growth and cell cycle progression. Oncogene 23: 3151-3171, 2004.
12. Fujita S, Dreyer HC, Drummond MJ, Glynn EL, Cadenas JG, Yoshizawa F, Volpi E, and Rasmussen BB. Nutrient signalling in the regulation of human muscle protein synthesis. J Physiol (Lond) 582: 813-823, 2007.
13. Haff GG, Stone MH, Warren BJ, Keith R, Johnson RL, Nieman DC, Williams F, and Kirksey KB. The effect of carbohydrate supplementation on multiple sessions and bouts of resistance exercise. J Strength Cond Res 13: 111-117, 1999.
14. Hawley JA, Gibala MJ, and Bermon S. Innovations in athletic preparation: Role of substrate availability to modify training adaptation and performance. J Sports Sci 25: S115-S124, 2007.
15. Koopman R., Saris WH, Wagenmakers AJ, and Van Loon LJ. Nutritional interventions to promote post-exercise muscle protein synthesis. Sports Med 37: 895-906, 2007.
16. Kraemer WJ, Fragala MS, and Volek JS. Nutrition for muscle development. In: Strength Training. Brown LE, ed. Champaign, IL: Human Kinetics, 2007. pp. 73-94.
17. Laviano A, Muscaritoli M, Cascino A, Preziosa I, Inui A, Mantovani G, and Rossi-Fanelli F. Branched-chain amino acids: The best compromise to achieve anabolism? Curr Opin Clin Nutr Metab Care 8: 408-414, 2005.
18. Lecker SH, Solomon V, Mitch WE, and Goldberg AL. Muscle protein breakdown and the critical role of the ubiquitin-proteasome pathway in normal and disease states. J Nutr 129: S227-S237, 1999.
19. Manninen AH. Hyperinsulinaemia, hyperaminoacidaemia and post-exercise muscle anabolism: The search for the optimal recovery drink. Br J Sports Med 40: 900-905, 2006.
20. Murray R, Bartoli WP, Eddy DE, and Horn MK. Gastric emptying and plasma deuterium accumulation following ingestion of water and two carbohydrate-electrolyte beverages. Int J Sport Nutr 7: 144-153, 1997.
21. Price SR, Du JD, Bailey JL, and Mitch WE. Molecular mechanisms regulating protein turnover in muscle. Am J Kidney Dis 37: S112-S114, 2001.
22. Rasmussen BB, Tipton KD, Miller SL, Wolf SE, and Wolfe RR. An oral essential amino acid-carbohydrate supplement enhances muscle protein anabolism after resistance exercise. J Appl Physiol 88: 386-392, 2000.
23. Rasmussen CJ. Nutrition before, during, and after exercise for the strength/power athlete. In: Essentials of Sports Nutrition and Supplements. Antonio J, Kalman D, Stout JR, Greenwood M, Willoughby DS, and Haff GG, eds. New York, NY: Humana Press-Springer, 2008. pp. 647-665.
24. Sallinen J, Pakarinen A, Ahtiainen J, Kraemer WJ, Volek JS, and Hakkinen K. Relationship between diet and serum anabolic hormone responses to heavy-resistance exercise in men. Int J Sports Med 25: 627-633, 2004.
25. Stoppani J, Scheett TP, and Mcguiggan MR. Nutritional needs of strength/power athletes. In: Essentials of Sports Nutrition and Supplements. Antonio J, Kalman D, Stout JR, Greenwood M, Willoughby DS, and Haff GG, eds. New York, NY: Humana Press-Springer, 2008. pp. 349-370.
26. Tarpenning KM, Wiswell RA, Hawkins SA, and Marcell TJ. Influence of weight training exercise and modification of hormonal response on skeletal muscle growth. J Sci Med Sport 4: 431-446, 2001.
27. Tipton KD, Elliott TA, Cree MG, Aarsland AA, Sanford AP, and Wolfe RR. Stimulation of net muscle protein synthesis by whey protein ingestion before and after exercise. Am J Physiol Endocrinol Metabol 292: E71-E76, 2007.
28. Volek JS. Strength nutrition. Curr Sports Med Rep 2: 189-193, 2003.
29. Volek JS. Influence of nutrition on responses to resistance training. Med Sci Sports Exerc 36: 689-696, 2004.
30. Volek JS, Kraemer WJ, Bush JA, Incledon T, and Boetes M. Testosterone and cortisol in relationship to dietary nutrients and resistance exercise. J Appl Physiol 82: 49-54, 1997.

resistance training; carbohydrates; protein; amino acids; hypertrophy

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