Abstract
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.
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Acknowledgements
Professor Paulo S.C. Gomes is a recipient of a Productivity Research Fellowship from Conselho Nacional de Desenvolvimento Tecnológico (CNPq) from Brazil. Thiago S. Álvares is supported by a research scholarship from CNPq. The authors have no conflicts of interest that are directly relevant to the content of this review. The authors would like to thank Ricky Toledano for the preparation of the English version of the manuscript.
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Álvares, T.S., Meirelles, C.M., Bhambhani, Y.N. et al. L-Arginine as a Potential Ergogenic Aidin Healthy Subjects. Sports Med 41, 233–248 (2011). https://doi.org/10.2165/11538590-000000000-00000
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DOI: https://doi.org/10.2165/11538590-000000000-00000