biostudies-literatureGambardella JItalian Ministry of Research PRIN6684568https://www.ebi.ac.uk/biostudies/studies/S-EPMC7994081biostudies-literatureUnknown2021<h4>Background</h4>Ergogenic nutritional supplementation is sought by professional athletes for improving physical performance; nevertheless, scientific evidence to support the chronic use of L-Arginine among water polo players is missing.<h4>Methods</h4>Seventeen male professional water polo players were randomly assigned to assume 5 grams per day of L-Arginine (<i>n</i> = 9) or placebo (<i>n</i> = 8) for 4 weeks. The players' fitness level was assessed in the maximal speed swimming test. Ear lobe blood samples taken before and after the effort for serum lactate content were analyzed. A speed-to-lactate ratio was generated at the baseline and after 4 weeks of treatment. We also tested the effects of L-Arginine <i>in vitro</i>, measuring NO production, mitochondrial respiration, and gene expression in human fibroblasts.<h4>Results</h4>L-Arginine did not modify BMI, muscle strength, and maximal speed at 200 meters after 4 weeks. However, L-Arginine ameliorated oxidative metabolism to exercise as suggested by the statistically significant lower lactate-to-speed ratio, which was not observed in placebo-treated controls. <i>In vitro</i>, L-Arginine induced the expression of a key regulator of mitochondrial biogenesis (PGC1<i>α</i>) and genes encoding for complex I and increased the production of nitric oxide and the maximal oxygen consumption rate.<h4>Conclusions</h4>Chronic L-Arginine is safe and effective in ameliorating the oxidative metabolism of professional water polo players, through a mechanism of enhanced mitochondrial function.Oxidative medicine and cellular longevityEffects of Chronic Supplementation of L-Arginine on Physical Fitness in Water Polo Players.PMC79940812017HTKLRFSantulli GLungonelli GTrimarco VCerasuolo FADi Vaia ESorriento DGambardella JFiordelisi ABoldrini LIaccarino GSpigno LfalseEffects of Chronic Supplementation of L-Arginine on Physical Fitness in Water Polo Players.<h4>Background</h4>Ergogenic nutritional supplementation is sought by professional athletes for improving physical performance; nevertheless, scientific evidence to support the chronic use of L-Arginine among water polo players is missing.<h4>Methods</h4>Seventeen male professional water polo players were randomly assigned to assume 5 grams per day of L-Arginine (<i>n</i> = 9) or placebo (<i>n</i> = 8) for 4 weeks. The players' fitness level was assessed in the maximal speed swimming test. Ear lobe blood samples taken before and after the effort for serum lactate content were analyzed. A speed-to-lactate ratio was generated at the baseline and after 4 weeks of treatment. We also tested the effects of L-Arginine <i>in vitro</i>, measuring NO production, mitochondrial respiration, and gene expression in human fibroblasts.<h4>Results</h4>L-Arginine did not modify BMI, muscle strength, and maximal speed at 200 meters after 4 weeks. However, L-Arginine ameliorated oxidative metabolism to exercise as suggested by the statistically significant lower lactate-to-speed ratio, which was not observed in placebo-treated controls. <i>In vitro</i>, L-Arginine induced the expression of a key regulator of mitochondrial biogenesis (PGC1<i>α</i>) and genes encoding for complex I and increased the production of nitric oxide and the maximal oxygen consumption rate.<h4>Conclusions</h4>Chronic L-Arginine is safe and effective in ameliorating the oxidative metabolism of professional water polo players, through a mechanism of enhanced mitochondrial function.2021-01-01T00:00:00Z20212024-10-19T08:13:59.001Z2022-02-09T12:47:00.772ZS-EPMC79940813381565710.1155/2021/6684568