Exercise and Nutrition Mythbusters: What should I Eat Post Exercise? (It's Not Just Protein!)

We have all heard that protein intake builds muscle, but you may or may not have heard that you need to ingest protein immediately following exercise to capitalize on muscle synthesis. The reasoning is that this is thought to be the window of opportunity for the muscle to maximize anabolism. However, is protein the only piece to the muscle building puzzle? Apologies go out to all the “meatheads” in the world, but protein is actually only a very small piece of the anabolism process for an athlete.

Athletes who only ingest protein following their workouts are really missing out on maximizing their muscle gains. If you read my recent blog on “carbohydrate loading”, you would know that high intensity exercise drastically decreases muscle glycogen stores, which the body uses as a major energy resource. Those muscle glycogen stores need to be replenished after the workout to bring those stores up in preparation for the next workout or event. This is usually done through the ingestion of carbohydrates.

John Ivy, of University of Texas, “observed that muscle glycogen synthesis is twice as rapid if carbohydrate is consumed immediately after exercise as opposed to waiting several hours (timing is key), and that a rapid rate of synthesis can be maintained if carbohydrate is consumed on a regular basis. For example, supplementing at 30-min intervals at a rate of 1.2-1.5 grams of carbohydrate per kilogram of body weight appears to maximize synthesis for a period of 4-5 hours post exercise.” 2) The reason why you want to start carbohydrate ingestion right away is because your body is so insulin sensitive. This is important because insulin stimulates glucose uptake by the muscle and the conversion of glucose into highly valuable glycogen. Not to mention the ability of insulin to increase the rate of protein synthesis when the the carb combo is taken immediately after exercise.” 2)

Although it seems like like this article is bashing protein, its’ importance is not forgotten. Protein does have it’s place, and it belongs right along side an ingestion of carbohydrate post-exercise to prevent proteolysis (muscle protein breakdown). Loon, et. al, (2000) conducted a study comparing insulin responses, which are important in protein synthesis and glycogen synthesis, between various post workout carbohydrate solutions, such as carb, carb-carb, and carb-protein. He discovered, “The ingestion of a mixture of wheat hydrolysate protein and free leucine and phenylanine (both are muscle building Branch Chain Amino Acids) in combination with carbohydrate can result in an 88% higher post exercise insulin response than that of the carbohydrate mixture.” 1) Loom also showed that “the protein-carbohydrate mixture intake (.8 g.kg-1.h-1) provided at 30-min intervals, resulted in a significant increase in glycogen synthesis rates (113%).” 1)

In review, immediately during post exercise you should ingest a high glycemic carbohydrate and quality protein mixture (ratio of 3:1). For example, Gold Standard 100% Whey Protein. Don’t stop there either, continue to ingest in 30-120 min increments for a total of 8 hours post workout to maximize muscle glycogen synthesis. If you really want to maximize your gains, be smart and precise with your nutrition.

1. Loom, L., Saris, W., Kruijshoop, M., & Wagenmakers, A. (2000). Maximizing

postexercise muscle glycogen synthesis: Carbohydrate supplementation and the application of amino acid or protein hydrolysate mixtures1–3. The American Journal of Clinical Nutrition, 72(1), 106-111. Retrieved November 7, 2014, from http://ajcn.nutrition.org/content/72/1/106.full.pdf html

2. Randall, K. (2004, January 1). Timing is Everything. Retrieved November 7, 2014, from

https://www.utexas.edu/features/archive/2004/nutrition.html