The best athletes can train hard, recover quickly, and train hard again.  David Pearson from Ball State University and Carwyn Sharp found amino acid supplements taken for four weeks promoted recovery from an intense workout.  During recovery following amino acid supplementations, athletes showed higher levels of testosterone and lower levels of cortisol (breaks down tissue) and creatine kinase (marker of muscle damage).  Dialy amino acid intake from the supplement included 2,000 micrograms of L-glutamine, 1,800 micrograms of L-leucine, 700 micrograms of L-isoleucine, and 750 micrograms of L-valine.  Amino acids are the building blocks of proteins but some act as signaling chemicals for important metabolic pathways that synthesize proteins and promote tissue repair.  Intense training is the key to building strength, power, and muscle mass.  Amino acid supplements might help you train hard, recover, and then train hard again.  (Journal Strength Conditioning Research, 24:  1125-1130, 2010)

The branched chain amino acids (BCAA) include leucine, isoleucine, and valine.  They comprise about 18 percent of the total amino acids and 35 percent of the essential amino acids in skeletal muscle.  BCAA's decrease in muscle during intense exercise.  Japanese researchers found that supplying BCAA's before a workout decreased muscle damage and chemical markers of muscle cell damage by approximately 20 percent.  Muscle force measured three days after the workout was 20 percent greater in people who consumed the BCAA supplement.  (International Journal of Sport Nutrition and Exercise Metabolism, 20:  236-244, 2010)

Citrulline is a vital amino acid for maintaining metabolic health because it helps regulate nitric oxide (NO) production, which controls blood flow throughout the body.  NO is vital for muscle blood flow, sexual function, fuel and hormone delivery to muscles, tissue oxygenation, and general energy levels.  Spanish researchers found that a single dose of 8 grams of citrulline increased lifting endurance during the bench press, and decreased post exercise muscle soreness.  Citrulline supplements, sold in the form of citrulline malate, might reduce muscle soreness, improve weight training endurance, and prevent blood vessel damage that accompanies intense nitric oxide levels.

(Journal of Strength Conditioning Research, 24:  1215-1222, 2010)

Arginine is an amino acid that stimulates growth, helps make nitric oxide, promotes healing and tissue repair, and decreases blood pressure.  A review of literature from Texas A & M University concluded that arginine might also reduce body fat and help fight obesity.  Several studies found that L-arginine supplements reduced body fat. Arginine prevents fat cell growth and stimulates the growth of brown fat , a highly thermogenic tissue that speeds the rate the body burns calories and fat.  Also, arginine acts as a chemical energy signal that speeds metabolism.  They concluded that arginine is a safe, low cost nutrient that reduces body fat, increase muscle mass, and improves metabolic health.

(Amino Acids, in press;  Published online May 1, 2010)