By Anthony Roberts
A lot of people have been getting into the research on Arginine lately, as a potential ergogen (performance enhancer). Much of it’s purported effects, at least if one were to read (and believe) supplement advertisements, come from its ability to stimulate nitric oxide. But what does the research actually say? Well, a recent review of the literature, published in a peer-reviewed journal, indicates that chronic arginine supplementation is a 50/50 proposition at best – and even after being used for over a decade as a performance enhancer, the jury is still out on whether or not it actually improves performance. If we’re “not sure” if the stuff works after a decade of using the stuff, it’s a safe bet to say it’s a loser.
Sports Med. 2011 Mar 1;41(3):233-48. doi: 10.2165/11538590-000000000-00000.
L-Arginine as a potential ergogenic aid in healthy subjects.
Álvares TS, Meirelles CM, Bhambhani YN, Paschoalin VM, Gomes PS.
Laboratory Crossbridges, Center for Interdisciplinary Research in Health, Department of Physical Education, Universidade Gama Filho, Rio de Janeiro, Brazil.
Dietary supplements containing L-arginine, a semi-essential amino acid, are one of the latest ergogenic aids intended to enhance strength, power and muscle recovery associated with both aerobic and resistance exercise. L-arginine is claimed to promote vasodilation by increasing nitric oxide (NO) production in the active muscle during exercise, improving strength, power and muscular recovery through increased substrate utilization and metabolite removal, such as lactate and ammonia. Research on L-arginine has recently tested this hypothesis, under the assumption that it may be the active compound associated with the vasodilator effects of NO. There were only five acute studies retrieved from the literature that evaluated exercise performance after L-arginine supplementation, three of which reported significant improvements. Regarding studies on chronic effects, eight studies were encountered: four reported enhancements in exercise performance, whilst four reports showed no changes. Whether these improvements in exercise performance – regardless of the aerobic or anaerobic nature of the exercise – can be associated with increases in NO production, has yet to be demonstrated in future studies. Low oral doses (≤20 g) are well tolerated and clinical side effects are rare in healthy subjects. In summary, it is still premature to recommend dietary supplements containing L-arginine as an ergogenic aid for healthy physically active subjects.