Effect of nocturnal melatonin ingestion on short-term anaerobic performance in soccer players

Abstract

No study has examined whether nocturnal melatonin ingestion affects short-term maximal athletic performance. Therefore, the aim of this study was to investigate the effect of nocturnal melatonin ingestion on upper and lower body anaerobic performances. Twelve professional soccer players from a Tunisian league two squad (age: 22.9 ± 1.3yrs; height: 1.8 ± 0.05 m, and body mass 72.0 ± 8.8 kg) performed three testing sessions at 21:00 h (two melatonin sessions, 5 mg or 8 mg, and one placebo session) in a double-blind, counterbalanced protocol. During each session, 30 min after melatonin or placebo ingestion, subjects performed the following tests: the squat jump, the countermovement jump, the medicine-ball throw, the five jumps, the grip strength, and agility tests. In all tests, the results showed no difference between placebo and 5 mg melatonin ingestion (p < 0.05). However, short-term maximal performances were lower after 8 mg melatonin ingestion in comparison with the placebo ingestion (p < 0.05). In conclusion, although 8 mg of melatonin has an adverse effect on physical capacities, 5 mg of melatonin ingestion does not affect short-term maximal performance.