Acute supplementation of L-arginine affects neither strength performance nor nitric oxide production

J Sports Med Phys Fitness. 2018 Mar;58(3):216-220. doi: 10.23736/S0022-4707.16.06680-9. Epub 2016 Sep 13.

Abstract

Background: L-arginine is a semi-essential amino acid involved in nitric oxide production. As nitric oxide is an important vasodilator, L-arginine supplementation would increase blood perfusion and, subsequently, muscle performance during exercises. The aim of this study was to determine the acute effect of L-arginine supplementation on strength performance and nitric oxide levels in healthy trained individuals.

Methods: In a double-blind, placebo-controlled, cross-over study, 12 men were randomly assigned to L-arginine or placebo supplementation. Subjects received 6 g of L-arginine or placebo 60 minutes before strength test (maximum number of repetitions, 3 sets at 70% of one repetition maximum on bench press and at 80% of one repetition maximum on knee extensions, 2 minutes of rest between sets and exercises). Blood samples were collected before supplementation and 6 min after exercise.

Results: Plasma nitrite levels did not significantly change after L-arginine or placebo supplementation and strength-training exercise (placebo, from 13.01±1.18 to 11.83±2.81 mM; L-arginine, from 10.95±4.09 to 11.99±2.5 mM). There was a significant reduction in the number of repetitions performed from set 1 to set 3 in each set of both bench press and knee extension, but no significant interactions were observed between placebo and L-arginine.

Conclusions: These results do not support the use of L-arginine as an ergogenic aid for strength performance, at least in context of acute use immediately before resistance exercise performance.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Arginine / administration & dosage
  • Arginine / metabolism*
  • Athletic Performance*
  • Cross-Over Studies
  • Dietary Supplements / analysis*
  • Double-Blind Method
  • Exercise / physiology
  • Humans
  • Male
  • Muscle, Skeletal / metabolism
  • Nitric Oxide / metabolism*
  • Nitrites / blood
  • Resistance Training
  • Young Adult

Substances

  • Nitrites
  • Nitric Oxide
  • Arginine