There have been a lot of conversations about protein supplementation and its effect on muscle growth and its role in muscle development in athletes and recreational athletes. Some argue that it is important to supplement prior to and immediately post exercise. Whereas, others have argued that it is best to just supplement at anytime during the day. So, does it really matter when you supplement with protein? The answer is yes and no. It is obvious that resistance athletes must consume upwards of 30% - 50% more protein than that of an endurance athlete (Hoffman et al., 2009). Also, there is evidence that exercise, particularly resistance training and lengthy endurance training, can produce a catalytic (breakdown) cycle within the muscular structure during and post exercise (Ivy & Furguson., 2010) and that this catalytic cycle can lead to reductions in force, power, and strength of future workouts. For a positive recovery to occur a shift must be made from a catalytic state to an anabolic state, and this is why it is believed that the optimal window for a post-exrecise meal is within 30 - 60 minutes (Ivy & Ferguson, 2010). Also, intense exercise enhances protein synthesis, as well as, protein degradation; for this reason it is important to have amino acid availability to mediate the balance between degradation and synthesis (Ferguson-Stegall et al., 2011). Athletes that supplement or increase their protein intake have been shown to increase muscular recovery, decrease muscle damage, and also a reduction in force decrements (Hoffman et al., 2009). So when is it considered the best time to supplement? Is there an optimal ratio between carbohydrates (CHO) and protein? What protein source seems to be the best? There is a large amount of evidence out there that supports supplementation of protein by the athlete, but the differences in the results within research can make determining an ideal protein ingestion window challenging.
Most studies that have researched the subject of protein supplementation explore timing, protein source, simple protein supplementation, and dosage size in relation to athlete or non-athletes. Previous studies have demonstrated that protein supplementation at or above recommended levels did not improve lean mass, strength or power in strength and power athletes, however, it is unknown what the parameters were for those studies and whether the participants were heavily observed throughout the course of the studies (Hoffman et al., 2009,). Also, of note is that in one study involving timing where male athletes ages 19 - 23 years in age reported better lean mass gains from protein supplementation when compare to elderly men whom also participated in the same study. Despite these gains it should be noted that there may have been some hormonal differences that lead to the increased gains in the younger athletes (Hoffman et al., 2009,). It was also noted that an increase in the amino acid leucine, found in milk, may have offset those negative muscle gain results in elderly men (Hulmi, Lockwood & Stout., 2010). When comparing protein supplementation in a previous study, they found that recreational athletes ages 21 - 24 supplementing with 44g of whey protein and 43 g of glucose (1:1 ratio) immediately prior to and post exercise showed the greatest improvement in lean body mass and cross sectional type II muscle fiber size when compared to a similar group that supplemented in the morning and evening (Hoffman et al., 2009). This previous study contradicted the study by Hoffman et al., that found similar results for both the morning and evening group along with the pre & post exercise group when supplementing with 42 g of a proprietary blend of protein (whey and casein). In short both groups showed adequate increases in strength, 1RM, and power, but timing did not make a difference between the statistics between the two groups. This may be because the athletes daily intake of protein was well above the recommended 1.6 - 2.0g/kg, and that the amount of carbohydrates (CHO) in the supplement mixture could have been too low to enhance protein metabolism facilitation (Hoffman et al., 2009) and this might have caused an overload on one singular metabolic pathway (Hulmi, Lockwood & Stout., 2010). It should be noted that for resistance training the amount of CHO should be between 1.2g and 1.5 g/kg along with 0.4g to 0.6 g/kg of protein at the time of supplementation (Ivy & Ferguson., 2010), and that protein intake should not exceed 2.0 g/kg/d. This is close to a 3:1 CHO:Protein ratio.
Blacker, S. D., Williams, N. C., Fallowfield, J. L., Bilzon, J. LJ., & Willems, M., ET. (2010). Carbohydrate vs protein supplementation for recovery of neuromuscular function following prolonged load carriage. Journal of the International Society of Sports Nutrition, 7:2.
Ferguson-Stout, L., McCleave, E. L., Ding, Z., Doerner III, P. G., Wang, B., Liao, Y-H., Kammer, L., Liu, Y., Hwang, J., & Dessard, B. M. (2011). Postexercise carbohydrate-protein supplementation improves subsequent exercise performance and intracellular signaling for protein synthesis. Journal of Strength and Conditioning Research, 25(5). 1210 - 1224.
Hoffman, J. R., Ratamess, N. A., Tranchina, C. P., Rashti, S. L., Kang, J., & Faigenbau, A. D. (2009). Effects of protein-supplement timing on strength, power, and body-composition changes in resistance-trained men. International Journal of Sports Nutrition and Exercise Metabolism, 19. 172 - 185.
Hulmi, J. J., Lockwood, C. M., & Stout, J. R. (2010). Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein. Nutrition & Metabolism, 7:51.
Ivy., J. L., & Ferguson, L. F. (2010). Optimizing resistance exercise adaptations through the timing of post-exercise carbohydrate-protein supplementation. Strength and Conditioning Journal, 32(1). 30 - 36.