Athletes and Protein

Fitness Handout:

As an athlete, you want to make sure you fuel your body in a way that supports performance in your sport—and life. How much and what kind of protein is best?

Natalie Digate Muth, MD, MPH, RD, a graduate of the University of North Carolina School of Medicine, a registered dietitian and an American Council on Exercise master trainer, offers practical tips on how to choose protein sources.

Protein Quality

Several scales are used to evaluate protein quality. However, the most widely used and most accepted method is called the protein digestibility–corrected amino acid score (PDCAAS). The proteins with the highest (i.e., best) PDCAAS scores are whey, casein, egg, milk and soy proteins (Hoffman & Falvo 2004). Beef comes in next, followed by black beans, peanuts and wheat gluten (Hoffman & Falvo 2004). Fruits, vegetables, grains and nuts are incomplete proteins and must be combined over the day to ensure adequate intake of each of the essential amino acids.

Choosing the Right Protein Sources

While no one type of protein is best for everyone, bear these points in mind:

Protein Does Not Exist in a Vacuum. Remember that other macronutrients also come into play. For example, while beef is a fairly good protein source, it is also high in saturated fat and calories. For example, a 6-ounce broiled porterhouse steak contains 38 grams (g) of protein, but it also delivers 44 g of fat, 16 of them saturated—almost three-fourths of the recommended daily intake for saturated fat. The same amount of salmon gives you 34 g of protein and only 18 g of fat, 4 of them saturated (Harvard School of Public Health 2009).

Different Proteins Are Better at Different Times. For example, whey protein is digested rapidly, resulting in a short burst of amino acids into the bloodstream, whereas casein is digested slowly, resulting in a more prolonged release of amino acids (Dangin et al. 2002). If the goal is for amino acids to be available for muscle regeneration immediately following a workout, you should time your protein intake accordingly.

A High-Protein Diet Is Not for Everybody. Individuals with pre-existing illnesses such as kidney disease, osteoporosis, diabetes or liver disease should consult with their physician prior to adopting a high-protein diet (St. Jeor et al. 2001).

For the latest research, statistics, sample classes, and more, "Like" IDEA on Facebook here.


Dangin, M., et al. 2002. Influence of the protein digestion rate on protein turnover in young and elderly subjects. Journal of Nutrition, 132, 3228S–33S.

Harvard School of Public Health. 2009. The Nutrition Source. Protein: Moving closer to center stage.; retrieved Jan. 13, 2009.

Hoffman, J.R., & Falvo, M.J. 2004. Protein: Which Is best? Journal of Sports Science & Medicine, 3, 118–30.

St. Jeor, S.T., et al. 2001. Dietary protein and weight reduction: A statement for healthcare professionals from the nutrition committee of the Council on Nutrition, Physical Activity, and Metabolism of the American Heart Association. Circulation, 104, 1869–74.
March 2010

© 2010 by IDEA Health & Fitness Inc. All rights reserved. Reproduction without permission is strictly prohibited.

Get the award-winning IDEA Fitness Journal delivered to your door every month!

Get IDEA Fitness Journal

Article Comments

Add Comment

View all questions