Protein and Amino Acids for Athletes

    * Aug 13, 2011
    * Jenny Mulligan

High-quality dietary protein helps optimize your athletic performance. - Ethan Lofton

As an athlete, the amount and quality of your dietary protein affects your sports performance.

Protein serves many functions in your body. It supports a healthy immune system, synthesizes blood cells, manufactures enzymes and produces hormones. As an athlete, your dietary protein also builds, repairs and maintains your muscle tissue. The amino acids in the proteins you eat – both quantity and quality – are therefore critical to your sports performance.

Protein Basics

The protein you consume in your diet provides your body with a pool of amino acids. Amino acids are small building blocks that join together in a specific sequence to create unique proteins as your body requires them – for example, new muscle in response to a weight-lifting session. Of the 20 amino acids in foods, nine are essential to your diet because your body cannot synthesize them. Your body does not store amino acids the way it does fats and carbohydrates, and you must therefore include protein in your diet every day to provide your body with the amino acids it needs. As an athlete, the amount of protein to meet your daily requirement depends on your weight and on the type of sport you participate in.

Protein Needs as an Athlete

Sedentary individuals require 0.8 g of high-quality protein per kg of body weight each day, writes Bill Campbell in the September 2007 issue of the Journal of the International Society of Sports Nutrition. Athletes need considerably more than this level of protein intake to account for the higher turnover of muscle protein and amino acids during and after exercise. The more intense work your muscles perform, the greater your protein and amino acid needs. For example, endurance athletes, such as long distance runners, should consume 1 to 1.6 g per kg, while those engaging in intermittent sports, including basketball and soccer, need 1.4 to 1.7 g protein for each kg they weigh. Strength and power athletes who place great demands on their muscles require 1.6 to 2 g per kg daily to meet their amino acid needs.
Branched-Chain Amino Acids

The branched-chain amino acids, isoleucine, leucine and valine, play a special role in sports nutrition. These three amino acids comprise roughly 33 percent of your skeletal muscle. In addition to their structural function, they help prevent protein degradation and promote protein synthesis both during and after an exercise session. Unlike other amino acids, the branched-chain amino acids absorb directly into your muscle tissue rather than undergoing prior metabolism by your liver, states sports nutritionist Nancy Clark. Additionally, branched-chain amino acids may lessen feelings of fatigue during extended aerobic-based sports. Campbell reports this effect may be due to these amino acids replacing tryptophan - an amino acid that increases serotonin levels, leading to the sensation of fatigue - in your brain.

Sources of High-Quality Protein

High-quality proteins contain all your essential amino acids and are found in animal-based foods such as milk products, eggs, meat and fish. Most plant proteins are lower-quality proteins because they lack at least one essential amino acid. However, you can consume different plant protein sources to meet your amino acid needs as an athlete. For example, nut butter on a whole-wheat bagel or black beans on a corn tortilla provide all the amino acids your body requires. Protein supplements also provide the full complement of essential amino acids, and whey protein, in particular, is rich in branched-chain amino acids. However, consult with a sports nutritionist before adding supplements to your diet.

Disclaimer: The information contained in this article is for educational purposes only and should not be used for diagnosis or to guide treatment without the opinion of a health professional. Any reader who is concerned about his or her health should contact a doctor for advice.


Copyright Jenny Mulligan. Contact the author to obtain permission for republication.

Jenny Mulligan - A longtime Seattle resident, Jenny Mulligan writes on health and fitness topics, with a special interest in science-based ...




