Aim: Very few studies have investigated the temporal specificity of melatonin (MEL) ingestion upon short-term maximal athletic performances. The aim of the present study was to explore the effect of morning MEL ingestion on cognitive and physical performances measured in the afternoon. Methods: Twelve soccer players from a Tunisian squad (17.9 ± 1.3 years, 1.74 ± 0.06 m and 62.0 ± 8.8 kg) participated in the present study. They performed two testing sessions at 08:00 h, 12:00 h and 16:00 h after either MEL (5mg) or placebo (PLA) ingestion, in a randomized order. During each period, the participants performed the following cognitive and physical tests: reaction time and vigilance tests, medicine-ball throw (MBT), five jumps, handgrip strength (HG), and agility tests. Results: cognitive and physical performances were significantly higher at 16:00 h compared to 08:00 h during the two conditions (p < 0.05). Moreover, performances of MBT and HG were lower in the morning with MEL in comparison to PLA (p < 0.05). However, MEL ingestion did not affect physical and cognitive performances measured at 12:00 h and 16:00 h. Conclusion: morning MEL ingestion has no unfavourable effect on afternoon physical and cognitive performances in soccer players.

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.

No abstract

No abstract

Objectives Fatigue is a limiting factor for sport performance. For this reason, optimal recovery after training is just as critical as the training program itself, if not more. Indeed, there is a need for strategies that can facilitate recovery after training, and one such strategy is the ingestion of supplements like melatonin (MEL). This study aimed to evaluate if MEL intake could improve recovery of athletes after an intermittent training session (ITS). Methods Fifteen elite female athletes (17.4 ± 0.4 years, 76.4 ± 5.6 kg, 1.76 ± 0.04 m; mean ± standard deviation) participated in two testing campaigns. During each period, they performed a battery of physical and cognitive tests before and after an ITS, as well as after ingesting MEL (6 mg tablet) or placebo in a randomized design. The ITS comprised the modified agility T-test, squat jump, counter movement jump, maximum standing ball-throw velocity test, maximum jump ball-throw velocity test, and 20-m sprint. Oral temperature (OT) and vigilance were evaluated before and after the ITS. Rating of perceived exertion (RPE), blood lactate [La], and glucose [Gl] were recorded after each ITS. Results Short-term performance, recovery of physical performance, and OT were not affected by MEL ingestion after the ITS. Moreover, MEL did not affect cognitive performance or RPE scores after the ITS. However, [La] and [Gl] (p < 0.05 for both) were decreased after MEL ingestion. Conclusion MEL has no effect on the recovery of physical performance but may affect glucose utilization and lactate metabolism during the team-handball training session.