Proteins are polypeptides aka chains of amino acids. These essential amino acids (EAAs) and branched-chain amino acids (BCAAs) are essential organic compounds for repairing tissue and building it e.g. in the form of muscles, bones, skin, and blood. Proteins also have an important role related to hormone and enzyme functions. (Gangurde et al. 2011) Therefore, proper recovery and optimized muscle mass gain (hypertrophy) require proteins.

Milk, egg, soy, meat, and wheat are one of the protein sources found in food (Gangurde et al. 2011), and there are various opinions on which of these is superior. So, how can athletes recognize the correct types and amounts of protein, and consume them at the right time of the day? This blog post will handle these questions.

Quality

When comparing different protein sources, it is essential to estimate how effectively the body is able to absorb and utilize the specific protein. The most commonly used protein supplements are whey and casein. Both are found in milk, and protein content of cow’s milk constitutes by 20% of whey and 80% of casein. According to research by Gangurde et al. (2011), whey protein is the best protein source compared to any other proteins thanks to its highest biological value (see Table below). Whey protein has the highest concentrations of EAAs and BCAAs compared to other protein sources, e.g. meat, wheat, and soy. (Gangurde et al. 2011)

Eggs, on the other hand, offer a good protein source for athletes not able to consume lactose. Eggs also include all required amino acids. Digestion of casein takes longer compared to whey. Soy protein has comparable quality to casein, although it is digested rather slowly (in 2-4 hours), which makes it an ideal addition to meals rather than to protein supplements. However, recent studies indicate that consuming large amounts of soy protein may have several downsides. (Gangurde et al. 2011)

Creatine is a compound found mainly in muscle, and therefore vegetarians lack creatine from their diet (Jäger et al. 2017). Nevertheless, vegetarians can compensate the rather poorer quality of vegetarian and vegan protein sources compared to animal sources by consuming bigger amounts of proteins. When the protein amount is excessive, e.g. >40 grams, protein quality turns out to be less important. (Gangurde et al. 2011)

Timing

Regularly ingesting protein supplements after resistance training increases muscle mass and strength gains both for younger and older athletes (Cermak et al. 2012). On the other hand, endurance athletes should mainly focus on consuming enough carbohydrates as in case the amount of carbohydrates is appropriate, the increase of protein intake does not improve endurance performance. Protein supplements are beneficial for offsetting muscle damage and improving recovery also for endurance athletes. (Jäger et al. 2017)

Drinking a protein-rich recovery drink within an hour after the exercise training may be beneficial for muscle hypertrophy. But looking at the big picture, the most important factor affecting muscle hypertrophy is the daily and consistent protein consumption. (Schoenfeld et al. 2013) Protein consumption should, therefore, be distributed evenly throughout the day every 3-4 hours (Jäger et al. 2017).

There has been a lot of discussion whether it is beneficial to consume protein prior going to sleep, and whether this method stimulates protein synthesis in the night during the recovery phase. Trommelen and van Loon (2016) found that consuming 40 grams of protein just before going to sleep increases amino acid availability for the night and increases protein synthesis, especially in case the protein source is casein. Apparently also the muscle hypertrophy is increased with this method. (Jäger et al. 2017; Trommelen and van Loon 2016) In practice, it is still enough for most athletes to eat a protein-rich evening snack instead of protein supplements.

Amount

The optimal daily protein amount is 1,4-2,0 g/kg for athletes (Jäger et al. 2017), and the optimal amount of protein in one recovery drink is 0,3 g/kg which equals to 20-40 grams of protein depending on the athlete’s weight (Gangurde et al. 2011).

In case the daily protein amount exceeds 2,5 g/kg, it may overload the liver (Gangurde et al. 2011). Excessive amounts of proteins may also lead to a situation where the athlete’s nutrition lacks some important nutrients, e.g. vitamins and fatty acids. This is due the fact that protein is a great source for satiety, but in case the amounts are excessive, the feeling of hunger may be weakened and therefore the energy intake may not be sufficient. (Skov et al. 1999)

Best practices for protein consumption and timing

Protein supplements are usually an easy way to increase the protein intake and minimize caloric intake, but you can also get the appropriate amount of protein from whole foods (Gangurde et al. 2011; Jäger et al. 2017). Red meat is not recommended as the main protein source due to its content of saturated fat and other health-related side effect and disadvantages. Instead, to increase protein intake in general, add other protein sources to meals. Turkey and salmon are one of the best meat-based protein sources with low-fat contents in addition to plant-based soy. (Gangurde et al. 2011)

And remember: In case you find yourself replacing a healthy snack or meal (e.g. berries, vegetables, nuts, and fish) with protein supplements, it may be questionable whether it is healthy or not.

Sources

Cermak N. et al. 2012. Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis. American Journal of Clinical Nutrition 2012;96: 1454-64.

Gangurde H. et al. 2011. Whey protein. Review article. Department of Pharmaceutics, SNJB’s S.S.D.J., College of Pharmacy, Neminagar, Chandwad, Nasik, Maharashtra, India

Jäger R. et al. 2017. International Society of Sports Nutrition Position Stand: protein and exercise. Review. Journal of the International Society of Sports Nutrition 2017 14:20. https://doi.org/10.1186/s12970-017-0177-8

Schoenfeld B., Aragon A. and Krieger J. 2013. The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. Journal of the International Society of Sports Nutrition 2013, 10:53.

Skov A. et al. 1999. Randomized trial on protein vs carbohydrate in ad libitum fat reduced diet for the treatment of obesity. International Journal of Obesity 1999; 23, 528-536.

Trommelen J. and van Loon L. 2016. Pre-sleep protein ingestion to improve the skeletal muscle adaptive response to exercise training. Review. Nutrients 2016, 8, 763; doi: 10.3390/nu8120763.