This study found that whey protein caused a greater increase in muscle protein synthesis than soy protein, especially after exercise. However, soy is still a good option for vegan/vegetarian lifters! Other studies have found beef-based proteins to be similarly as effective as milk-based proteins which can be helpful for individuals with milk allergies.
The Study: Tang, J. E., Moore, D. R., Kujbida, G. W., Tarnopolsky, M. A., & Phillips, S. M. (2009). Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise in young men. Journal of Applied Physiology, 107(3), 987-992.
From being a mediocre athlete, to professional powerlifter and strength coach, and now to researcher and writer, Charlie combines education and experience in the effort to help Bridge the Gap Between Science and Application. Charlie performs double duty by being the Content Manager for The Muscle PhD as well as the Director of Human Performance at the Applied Science and Performance Institute in Tampa, FL. To appease the nerds, Charlie is a PhD candidate in Human Performance with a master’s degree in Kinesiology and a bachelor’s degree in Exercise Science. For more alphabet soup, Charlie is also a Certified Strength and Conditioning Specialist (CSCS), an ACSM-certified Exercise Physiologist (ACSM-EP), and a USA Weightlifting-certified performance coach (USAW).