L-arginine is an amino acid found in high protein-containing foods, such as animal products and nuts. The typical dietary suggested intake is 4–5 grams/day. The body not only obtains argine from food but is also synthesizes from citrulline mainly in the kidney.
Many experts suggest that supplementing with arginine enhances exercise and athletic performance in several ways. First, some arginine is converted to nitric oxide, a potent vasodilator that can increase blood flow and the delivery of oxygen and nutrients to skeletal muscle. Next, increased vasodilation can speed up the removal of metabolic waste products related to muscle fatigue, such as lactate and ammonia, that the body produces during exercise. Third, arginine serves as a precursor for the synthesis of creatine, which helps supply muscle with energy for short-term, intense activity. Fourth, arginine may help increase the secretion of human growth hormone (HGH), which in turn increases insulin-like growth factor-1 (IGF-1) levels, both of which stimulate muscle growth.
The research to support supplemental arginine as a performance enhancer is limited by itself but is often combined with other supplements such as BCAAs and glutathione. Results are conflicting but show significant positive outcomes than without supplementation. The most common doses were 2–10 g/day as a single dose and up to 20 g/day divided into three doses.
Safety: Most study results suggest that up to 9 g/day arginine for several days or weeks is safe and well tolerated. At higher doses of 9–30 g/day, the gastrointestinal discomfort, such as diarrhea and nausea, and slightly reduced blood pressure were most commonly reported adverse reactions.
Arginine:
- enhance strength
- improve exercise
- increase athletic performance
- promote muscular recovery after exercise
