Strength training is necessary for building muscle, and the foods and beverages consumed can affect your results from this exercise. The type of protein, amount of protein and timing of its consumption all enhance muscle synthesis, notes D.J. Weinert in the “Journal of the Canadian Chiropractic Association” from August 2009.
The International Society of Sports Nutrition, or ISSN, says the recommendation for protein intake for the average person of 0.4 g of protein per pound of body weight is insufficient for athletes. Rather, an exercising person should consume between 0.7 and 1.0 g of protein per pound of body weight daily.
Serious strength training individuals, such as bodybuilders, should consume closer to the 1 g per pound of body weight recommendation, while endurance athletes should aim for the lower end of the ISSN range. Even with these levels of protein intake, a person should not exceed the Institute of Medicine’s upper limits of safe protein intake of 35 percent of daily calories. The recommendation for protein intake and muscle building applies to both men and women.
Types of Protein
Protein is made up of amino acids, some of which are produced by the human body, but nine of them must be obtained from dietary sources. Foods that provide all nine of these essential amino acids in adequate amounts are known as complete proteins. Meats, poultry, fish, eggs, dairy and soy are examples of complete proteins. Most grain and vegetable proteins lack a complete amino acid profile. Certain proteins contain higher concentrations of the specific amino acids leucine, isoleucine and valine. These branched-chain amino acids make up one-third of skeletal muscle protein, and the ISSN notes that seeking out proteins with high amounts of these amino acids may further enhance muscle development. Whey protein and lean beef are good sources.
Consuming a serving of protein around the time of a workout can help enhance muscle growth, as well as assist in recovery. A study in the journal “Amino Acids” from 2007 found that ingesting 20 g of protein and amino acids one hour before and after exercise resulted in greater increases in muscle mass and strength after 10 weeks of resistance training than ingesting a carbohydrate supplement. The best sources of this protein are whole foods, says the ISSN.
Eating pounds of meat or guzzling supplements with 50 g or more of protein per serving will not further enhance muscle growth. A study in "Journal of the American Dietetic Association" from September 2009 found that while 30 g of protein enhances muscle synthesis by 50 percent, eating more protein than this does not contribute to any further gains. Thirty grams is about the amount found in 3.5 oz. of skinless chicken breast.
- "Amino Acids"; "Effects of Resistance Training and Protein Plus Amino Acid Supplementation on Muscle Anabolism, Mass and Strength"; D.S. Willoughby et al; 2007
- "Journal of the American Dietetic Association"; "A Moderate Serving of High-Quality Protein Maximally Stimulates Skeletal Muscle Protein Synthesis in Young and Elderly Subjects"; T. Brock Symons et al; September 2009
- "Journal of the International Society of Sports Nutrition"; "Position Stand: Protein and Exercise"; Bill Campbell et al; Sept. 26, 2007
- "Journal of the Canadian Chiropractic Association"; "Nutrition and Muscle Protein Synthesis: A Descriptive Review"; D.J. Weinert; August 2009