Eisa Khaleghimamaghani - Department of Exercise Physiology, University of Guilan, Rasht, Iran.
Farhad Rahmani-nia - Department of Exercise Physiology, University of Guilan, Rasht, Iran.
Hamid Arazi - Department of Exercise Physiology, University of Guilan, Rasht, Iran.

Purpose: Sleep deprivation (SD) affects exercise performance while supplements may modify these effects. However, the effect of melatonin (MEL) supplementation on this issue is not completely clear. Methods: 10 trained young males participated (age: 23.4±1.71 yr, height: 176±6.42 cm, weight: 74.28±6.69 kg, body fat: 13.4±2.75%) in four sessions, one and two had normal sleep (NSD), and sessions three and four were also deprived of sleep. Then, subjects using the double-blind design were divided into two groups of melatonin (MEL) supplements (10 mg MEL) or placebo (PLA). Following the implementation of the sleep protocol, the subjects were tested, they then consumedsupplement and waited 30 minutes for secondary measurements. During each measurement, physiological performance and salivary level of MEL and lactate were evaluated. Results: MEL supplementation was significantly different in salivary level of MEL (P<0.05). Heart rate (HR), systolic and diastolic blood pressure were significantly decreased in the group who consumed supplement (P<0.05), but no significant changes were observed in the salivary level of lactate (P> 0.05). Conclusions: The MEL supplementation increases the salivary level of MEL and reduces HR and blood pressure.

Ergogenic, Physiological, Circadian rhythm, Sleep, Melatonin, Lactate