Sports Nutrition - How Much Protein Do You Need After Exercise?

Protein intake is able to stimulate muscle protein synthesis (MPS) above basal rates (1,2), and this response is greater if combined with resistance training(3).

The muscle protein synthesis acute response from exercise is a dose-response depending upon exercise intensity and workload (4). At intensities greater than 60% 1-RM, exercise increases MPS 2- to 3-fold (4); the latency for exercise intensities of 6×8 repetitions at 75% 1-RM is <1 h (7). After a latent period after exercise of about 45 minutes to an hour MPS rises sharply (2-3 fold) between 45 and 150 min (4).

In the rested, fasted state, skeletal muscle is in a state of negative net protein balance (5). However, in response to amino acid (AA) or protein feeding, MPS rates increase resulting in a positive net protein balance (3,6). Over time the changes in fed and fasted periods and their relative protein balances results in either skeletal muscle increase of decrease (6).

The increased sensitivity of MPS in response to essential aminoacid intake after exercise (3) can last up to 24h (7), 24-48h (8,9) or even up to 72h (10). Therefore, repeated bouts of RE and protein feeding result in skeletal muscle hypertrophy (11).

Available evidence points to a 2025 g dose of high quality protein to maximally stimulate MPS after resistance exercise in young adults (1,2).


Moore et al. (12) examined a protein dose response relationship with MPS following RE. They fed whole-egg proteins after resistance exercise to young men with training experience varying between 4 months to 8 years. The training session consisted of a bout of unilateral lower-body resistance exercise.

They fed participants drinks containing 0, 5, 10, 20, or 40 g of whole egg protein after exercise and measured protein synthesis from the vastus lateralis and whole-body leucine oxidation over 4 h. MPS displayed a dose response to dietary protein ingestion and was maximally stimulated at 20 g with no statistically significant benefit with the ingestion of 40g.

At 20 g protein (≈8.6 g EAAs) there was a ≈93% increase in mixed-muscle FSR above the fasted condition; a dose of EAAs very similar to that seen at rest (10 g) (13). A previous study also confirmed the same observation (21g vs. 40g) (14).

In another study by Witard et al. (15), 80-kg resistance-trained, young men performed a bout of unilateral exercise (8 × 10 leg presses and leg extensions; 80% one-repetition maximum) and also ingested 0, 10, 20, or 40 g of whey protein isolate immediately (10 min) after exercise. They also measure MPS from the vastus lateralis muscle.

A 20-g dose of whey protein was sufficient to maximally stimulate postabsorptive rates of myofibrillar MPS in rested and exercised muscle. A dose >20 g stimulated amino acid oxidation and ureagenesis.

Similar results were also observed at rest (no exercise) using whole food; 30g of lean ground beef protein was just as effective as 90g at stimulating MPS in young and elderly subjects (16).

The ceiling on MPS may in part be explained by what has been termed the “muscle full effect” (17). The “muscle full” hypothesis (18) suggests an upper limit of AA delivery before muscle cells would no longer respond and start diverting them toward oxidation (19).

After a lag of around 30 min there is a large increase (3-fold) with MPS peaking around 1.5 h before returning to baseline by 2 h (20,21) despite continued increased availability of circulating amino acids and sustained ‘anabolic signaling’ (19,20) and about 3 hours long in response to a complete meal containing protein, carbohydrates, and fats (22).
However there is some evidence to suggest that the muscle full effect or the refractory effect is delayed by exercise at least up to 6 hours (not clear what happens between 6h and 24h post-exercise) (8).

Nevertheless, it appears that 20g of whey protein (0.25gprotein/kg) is sufficient to maximally stimulate MPS both at rest (13) and after exercise (23) regardless of training status (15). Protein intake per dose above this threshold is oxidized at a higher rate (12,15) and results in urea production (15).

But as other authors pointed out these studies are limited to lower limb resistance training only and “thus it remains unknown as to whether the absolute dose of protein required to maximally stimulate rates of MPS following whole-body RE is >20g.” (1).


The current thought is that the greater the lean body mass and muscle mass the greater the protein dose necessary for maximal stimulation of MPS (1,2,23). Another assumption is that the total amount of muscle involved in the exercise bout also will influence the MPS response.

Tipton et al. tested this hypothesis in young, resistance-trained males by examining the response of MPS to two doses of whey protein ingested following exercise involving a greater amount of muscle mass, that is, a whole-body exercise routine (24). The two groups also differed in LBM (65 kg LBM vs. 70 kg LBM). As with previous studies, they also measure MPS from the vastus lateralis muscle.

Results suggest that ingesting a 40 g dose of whey protein isolate stimulated MPS to a greater extent than a 20 g dose of whey protein isolate during acute 5h post workout, despite different amounts of LBM.  

Note the individual response, as always some respond better than others, in other words some may need more protein to get the same response as others.

Specifically, “myofibrillar FSR was 20% higher with ingestion of 40 g compared with 20 g of whey following whole-body resistance exercise, irrespective of group”.

Authors believe the most likely explanation for the results is the greater amount of muscle activated during the exercise bout following whole body training, compared to a bout of unilateral or bilateral leg resistance exercise in previous studies (12,15).

This challenges the general consensus that ingestion of 2025 g of protein after resistance exercise is sufficient for the maximal MPS (1,2,23). 

Resistance exercise enhances the delivery of amino acids into the working muscle by increasing blood flow (3,5), therefore the greater the amount of muscle worked during the training bout the greater the amount of aminoacids taken up by the muscles (24).

But, since amino acid availability to any single muscle may be limited with whole-body exercise, more protein is necessary to elicit a higher MSP response to any single muscle worked (24).

And more importantly, because of this authors pointed out that “mean FSR values are approximately 71% and 76% of the FSR values for the 20 and 40 g, respectively, doses of whey protein that we reported previously.”

Meaning that the response to any single muscle trained following whole body training is lower that if trained in a split fashion even if you take 40g of whey.

Following these observations, the ingestion of 20 g of whey protein may be insufficient after a whole-body resistance exercise for all muscles worked. In the 40g trial there were more amino acids available for all the exercised muscles and MPS measured in the legs likely was able to respond at a greater rate, but still below previous studies (at least for the vastus lateralis muscle) (24).

Authors concluded:

“Thus, it seems that the overall amount of muscle mass possessed by the individual is a less important determinant of the maximally effective dose of protein to ingest than the amount of muscle mass activated during exercise. We conclude that more protein is necessary for the increased stimulation of MPS following whole-body compared to unilateral or bilateral resistance exercise. Moreover, it is not possible to determine the dose of protein necessary to stimulate a maximal MPS response from our data. We examined the MPS response to two amounts of protein only” (24). 

So in practical terms and in principle, if you want to maximize the result or emphasize a specific muscle (perhaps lagging) you have two options: doing do split routines for that muscle, or perhaps ingesting more than 40g of whey following a whole body training session since more gets dispersed all over the body for all muscles worked.

Other populations

Diseased and older populations have different protein requirements. Older adults have “anabolic resistance” in response to ingestion of dietary protein and amino acids (25). As a consequence of aging, MPS becomes refractory to hyperaminoacidemia, particularly at lower protein intakes (26) meaning that healthy older men are less sensitive to low protein intakes and require a greater relative protein intake up to 0.40 g/kg (27) in a single meal than young men to maximally stimulate postprandial rates of MPS (27,28).

Keep in mind this is the estimated average value, the acute protein intake may be as high as 0.60 g/kg for some older men (depending on contributing factors to the “anabolic resistance” of MPS) and ~0.40 g/kg for some younger men (27).

A dysregulation of intracellular signaling (14), a reduction in postprandial nutritive blood flow (29), subclinical chronic inflammation (30), a greater splanchnic extraction of amino acids (31), and/or a reduction in habitual activity (32) are all contributor factors that may account for the “anabolic resistance” of MPS with aging.

Other factors independent of age are muscle disuse (32,33,34), disease status (30), and/or lower quality protein with lower leucine content (35,36).

Interestingly, 113.4 g of lean ground-beef patties can similarly increase the mixed-muscle FSR in both the elderly and the young by ≈51%, suggesting that a normal serving of beef provides enough AAs to overcome any deficiency in responsiveness (37).

Short term should not be necessarily translated into long-term gains

As noted before, the increase in MPS may be sustained for up to 24h (7), 24-48h (8,9) or even up to 72h (10). Another point is that acute measures (1-6h post exercise) of MPS were found not to be correlated with muscle hypertrophy following chronic resistance training (38).

Muscle protein breakdown is also important for the regulation of muscle hypertrophy on the long term, and the chronic (positive) balance between MPS and MPB is more important than considering acute rises in MPS.

It has been shown, as mentioned previously, a 50% increase in MPB over 3 h of post-resistance exercise recovery (5). This MPB can be reduced by 30% in response to 20g of EAA + 30g or 90g of CHO ingestion (39).

It is hard to translate acute effects of protein timing on MPS to chronic adaptations with exercise training. Several factors such as methods of measuring protein utilization, training status of subjects, exercise type and intensity, energy and carbohydrate content of the diet, type and timing of protein intake, and duration of the study all influence protein requirements (40).

New methodologies for measuring cumulative MPS (C-MPS), such as the deuterium oxide method should be applied to measure long-term responses in order to better understand the dynamic fluctuations in protein requirements (40).

Repeated RE-T results in early muscle hypertrophy, 34 weeks, with any further progression relatively slow in comparison, with increases in muscle size reported to be 515% by 8 weeks. Cumulative response to RE-T measured using D2O have demonstrated 30% increases in MPS over 1 week, in which this response becomes diminished with time and ensuing muscle hypertrophy (41).

Moreover, a meta-analysis examining protein timing and hypertrophy concluded that that total protein intake was the strongest predictor of muscular hypertrophy and that protein timing did not influence hypertrophy (42).

Bottom line, when you perform sessions of whole body training a 40g dose of whey protein might be more advantageous than 20g, however total daily protein intake is still more important.

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1. Morton, R. W., C. McGlory, and S. M. Phillips. 2015. Nutritional interventions to augment resistance training induced skeletal muscle hypertrophy. Front. Physiol. 6:245.
2. Witard, O. C., S. L. Wardle, L. S. Macnaughton, A. B. Hodgson, and K. D. Tipton. 2016. Protein considerations for optimising skeletal muscle mass in healthy young and older adults. Nutrients 8: doi: 10.3390/nu8040181.
3. Biolo, G., K. D. Tipton, S. Klein, and R. R. Wolfe. 1997. An abundant supply of amino acids enhances the metabolic effect of exercise on muscle protein. Am. J. Physiol. 273: E122E129.
4. Kumar V, Selby A, Rankin D, Patel R, Atherton P, Hildebrandt W, Williams J, Smith K, Seynnes O, Hiscock N & Rennie MJ (2009). Age-related differences in the dose–response relationship of muscle protein synthesis to resistance exercise in young and old men. J Physiol 587, 211–217
5. Biolo, G., S. P. Maggi, B. D. Williams, K. D. Tipton, and R. R. Wolfe. 1995. Increased rates of muscle protein turnover and amino acid transport after resistance exercise in humans. Am. J. Physiol. 268:E514E520.
6. Phillips,S.M.(2004).Protein requirements and supplementation in strength sports. Nutrition 20,689–695.doi:10.1016/j.nut.2004.04.009
7.Burd,N.A.,West,D.W.D.,Moore,D.R.,Atherton,P.J.,Staples,A.W.,Prior,T.(2011).Enhanced aminoacid sensitivity of myofibrillar protein synthesis persists for up to 24h after resistance exercise in young men. J.Nutr. 141, 568–573.doi:10.3945/jn.110.135038
8. Cuthbertson DJ, Babraj J, Smith K, Wilkes E, Fedele MJ, Esser K & Rennie M (2006). Anabolic signaling and protein synthesis in human skeletal muscle after dynamic shortening or lengthening exercise. Am J Physiol Endocrinol Metab 290, E731–E738.
9. Phillips SM, Tipton KD, Aarsland A,Wolf SE &Wolfe RR (1997). Mixed muscle protein synthesis and breakdown following resistance exercise in humans. Am J Physiol 273, E99–E107.
10. Creer, A, Gallagher, P, Slivka, D, Jemiolo, B, Fink, W, and Trappe, S. Influence of muscle glycogen availability on ERK1/2 and Akt signaling after resistance exercise in human skeletal muscle. J Appl Physiol 99: 950–956, 2005
11. Cermak,N.M.,Res,P.T.,Groot,L.C.,DeSaris,W.H.M.,and VanLoon,L.J. C.(2012). Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis. Am.J.Clin. Nutr. 96,1454–1464.doi:10.3945/ajcn.112.037556
12. Moore, D. R., M. J. Robinson, J. L. Fry, J. E. Tang, E. I. Glover, S. B. Wilkinson, et al. 2009. Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. Am. J. Clin. Nutr. 89:161168.
13. Cuthbertson D, Smith K, Babraj J,et al. Anabolic signaling deficits underlie amino acid resistance of wasting, aging muscle. FASEB J 2005; 19: 422– 4.
14. Tipton KD, Ferrando AA, Phillips SM, Doyle D Jr., Wolfe RR. Postexercise net protein synthesis in human muscle from orally administered amino acids. Am J Physiol 1999; 276: E628– 34.
15. Witard, O. C., S. R. Jackman, L. Breen, K. Smith, A. Selby, and K. D. Tipton. 2014. Myofibrillar muscle protein synthesis rates subsequent to a meal in response to increasing doses of whey protein at rest and after resistance exercise. Am. J. Clin. Nutr. 99:8695.
16. Symons,T.B.,Sheffield-Moore,M.,Wolfe,R.R.,and Paddon-Jones, D.(2009). A moderate serving of high-quality protein maximally stimulates skeletal muscle protein synthesis in young and elderly subjects. J.Am.Diet.Assoc. 109, 1582–1586.doi:10.1016/j.jada.2009.06.369
17. Atherton,P.J.,Etheridge,T.,Watt,P.W.,Wilkinson,D.,Selby, A.,Rankin,D., etal. (2010). Muscle full effect after oral protein: time-dependent concordance and discordance between human muscle protein synthesis and mTORC1 signaling. Am.J.Clin.Nutr. 92,1080–1088.doi:10.3945/ajcn.2010.29819
18. Millward DJ, Pacy PJ. Postprandial protein utilization and protein quality assessment in man. Clin Sci (Lond) 1995;88:597–606.
19. Bohe J, Low JF, Wolfe RR, Rennie MJ. Latency and duration of stimulation of human muscle protein synthesis during continuous infusion of amino acids. J Physiol 2001;532:575–9
20. Atherton PJ, Etheridge T, Watt PW, Wilkinson D, Selby A, Rankin D, Smith K & Rennie MJ (2010). Muscle full effect after oral protein: time-dependent concordance and discordance between human muscle protein synthesis and mTORC1 signaling. Am J Clin Nutr 92, 10801088.
21.  Anthony JC, Lang CH, Crozier SJ, Anthony TG, MacLean DA, Kimball SR, Jefferson LS.  Contribution of insulin to the translational control of protein synthesis in skeletal muscle by leucine. Am J Physiol Endocrinol Metab. 2002 May;282(5):E1092-101.
22. Norton LE, Layman DK, Bunpo P, Anthony TG, Brana DV, Garlick PJ.  The leucine content of a complete meal directs peak activation but not duration of skeletal muscle protein synthesis and Mammalian target of rapamycin signaling in rats.  J Nutr. 2009 Jun;139(6):1103-9.
23. Churchward-Venne, T. A., N. A. Burd, and S. M. Phillips. 2012. Nutritional regulation of muscle protein synthesis with resistance exercise: strategies to enhance anabolism. Nutr. Metab. (Lond) 9:40.
24. Lindsay S. Macnaughton, Sophie L. Wardle1, Oliver C. Witard1, Chris McGlory, D. Lee Hamilton, Stewart Jeromson, Clare E. Lawrence, Gareth A. Wallis & Kevin D. Tipton. 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, 4 (15), 2016, e12893, doi:10.14814/phy2.12893
25. Bauer J, Biolo G, Cederholm T, et al. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. J Am Med Dir Assoc. 2013;14:542–559. doi:10.1016/j.jamda.2013.05.021.
26. Paddon-Jones D, Short KR, Campbell WW, Volpi E, Wolfe RR. Role of dietary protein in the sarcopenia of aging. Am J Clin Nutr. 2008;87:1562S–1566S.
27.Daniel R. Moore, Tyler A. Churchward-Venne,  Oliver Witard, Leigh Breen, Nicholas A. Burd,
Kevin D. Tipton, Stuart M. Phillips. Protein ingestion to stimulate myofibrillar protein synthesis requires greater relative protein intakes in healthy older versus younger men. J. Gerontol. A Biol. Sci. Med. Sci. 70:5762.
28. Katsanos CS, Kobayashi H, Sheffield-Moore M, Aarsland A, Wolfe RR. Aging is associated with diminished accretion of muscle proteins after the ingestion of a small bolus of essential amino acids. Am J Clin Nutr. 2005;82:1065–1073.
29. Timmerman KL, Lee JL, Fujita S, et al. Pharmacological vasodilation improves insulin-stimulated muscle protein anabolism but not glucose utilization in older adults. Diabetes. 2010;59:2764–2771. doi:10.2337/db10-0415
30. Walrand S, Guillet C, Salles J, Cano N, Boirie Y. Physiopathological mechanism of sarcopenia. Clin Geriatr Med. 2011;27:365–385. doi:10.1016/j.cger.2011.03.005.
31. Volpi E, Mittendorfer B, Wolf SE, Wolfe RR. Oral amino acids stimulate muscle protein anabolism in the elderly despite higher first-pass splanchnic extraction. Am J Physiol. 1999;277(3 Pt 1):E513–E520.
32. Breen L, Stokes KA, Churchward-Venne TA, et al. Two weeks of reduced activity decreases leg lean mass and induces “anabolic resistance” of myofibrillar protein synthesis in healthy elderly. J Clin Endocrinol Metab. 2013;98:2604–2612. doi:10.1210/jc.2013-1502
33. Drummond MJ, Dickinson JM, Fry CS, et al. Bed rest impairs skeletal muscle amino acid transporter expression, mTORC1 signaling, and protein synthesis in response to essential amino acids in older adults. Am J Physiol Endocrinol Metab. 2012;302:E1113–E1122. doi:10.1152/ajpendo.00603.2011
34. Glover EI, Phillips SM, Oates BR, et al. Immobilization induces anabolic resistance in human myofibrillar protein synthesis with low and high dose amino acid infusion. J Physiol. 2008;586(Pt 24):6049–6061. doi:10.1113/jphysiol.2008.160333
35. 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 (1985). 2009;107:987–992. doi:10.1152/japplphysiol.00076.2009
36. Yang Y, Churchward-Venne TA, Burd NA, Breen L, Tarnopolsky MA, Phillips SM. Myofibrillar protein synthesis following ingestion of soy protein isolate at rest and after resistance exercise in elderly men. Nutr Metab (Lond). 2012;9:57. doi:10.1186/1743-7075-9-57
37. T Brock Symons, Scott E Schutzler, Tara L Cocke, David L Chinkes, Robert R Wolfe, and Douglas Paddon-Jones . Aging does not impair the anabolic response to a protein-rich meal. Am J Clin Nutr 2007;86:451– 6.
38. Mitchell CJ, Churchward-Venne TA, Parise G, Bellamy L, Baker SK, et al. (2014) Acute Post-Exercise Myofibrillar Protein Synthesis Is Not Correlated With Resistance Training-Induced Muscle Hypertrophy in Young Men. PLoS ONE 9(2): e89431
39. Erin L. Glynn, Christopher S. Fry, Micah J. Drummond, Hans C. Dreyer, Shaheen Dhanani, Elena Volpi, Blake B. RasmussenMuscle protein breakdown has a minor role in the protein anabolic response to essential amino acid and carbohydrate intake following resistance exercise. Am J Physiol Regul Integr Comp Physiol. 2010 Aug; 299(2): R533–R540.  doi: 10.1152/ajpregu.00077.2010
40. Erin Simmons, James D. Fluckey, Steven E. Riechman. Cumulative Muscle Protein Synthesis and Protein Intake Requirements. Annu Rev Nutr. 2016 Jul 17;36:17-43. doi: 10.1146/annurev-nutr-071813-105549.
41. MATTHEWS. BROOK, DANIEL J. WILKINSON, KENNETH SMITH, & PHILIP J. ATHERTON. The metabolic and temporal basis of muscle hypertrophy in response to resistance exercise. European Journal of Sport Science, 2015.
42. Schoenfeld,B.J.,Aragon,A.A., Krieger, J.W.(2013).The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. J.Int.Soc.Sports Nutr. 10:53.doi:10.1186/1550-2783-10-53