As an athlete, the quantity and quality of protein in your diet affect your performance.
Protein serves many functions in your body. For example, it supports a healthy immune system, synthesizes blood cells, manufactures enzymes, and produces hormones. Your dietary protein also builds, repairs, and maintains your muscle tissue as an athlete. Therefore, the amino acids in the proteins you eat – both quantity and quality – are critical to your sports performance.
The protein you consume in your diet provides your body with a pool of amino acids. Amino acids are tiny 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.
Nine amino acids are required in your diet since your body cannot generate them. In addition, 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 required to meet your daily requirement depends on your weight and 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 Sports Nutrition. However, 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 of protein for each kg they weigh. Strength and power athletes who place significant demands on their muscles require 1.6 to 2 g per kg daily to meet their amino acid needs.
Branched-Chain Amino Acids
It is a branched-chain amino acid that plays a unique 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.
In contrast to other amino acids, Branched-chain amino acids are absorbed directly into muscle tissue rather than being processed by the 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. Conversely, most plant proteins are of inferior quality because they lack 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 provides all your body’s amino acids. 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.