Influence of Acute Melatonin Administration on Human Physical Performance: A Systematic Review

Abstract

Context: Melatonin is an ancient molecule with a wide range of functions in mammals, such as antioxidant, anti-inflammatory, and hypothermic effects among others. However, the influence of acute melatonin administration on human physical performance is debatable. Objective: To summarize available data from controlled trials about the effects of acute melatonin administration on human physical performance, especially with respect to strength, power, speed, and short- and long-term continuous exercise. Data Sources: A systematic search of the PubMed, Web of Science, Scopus, Embase, and Cochrane databases up to December 10, 2021, was conducted using specified keywords and Boolean operators (“melatonin” AND “exercise OR circuit-based exercise OR plyometric exercise OR exercise tolerance OR exercise test”). Study Selection: Only controlled studies in the English language and with humans were accepted. Study Design: Systematic review. Level of Evidence: Level 1. Data Extraction: Participants’ characteristics (sex, age, body mass, height and fat percentage), melatonin dose and administration time, and outcomes from the performance trial were extracted. Results: A total of 10 studies were identified after the screening process. Overall, melatonin did not change speed or short-term continuous exercise performances. However, in relation to strength and power, the results are debatable since 5 articles showed no difference, while another 2 pointed to a decrease in performance. In terms of performance improvement, only 1 study reported an increase in balance and another in long-term continuous exercise performance in nonathletes, with no advantage found for athletes. Conclusion: Melatonin did not cause any significant change in strength, speed, power, and short-term continuous exercise performances. In fact, it led to reduced strength and power performances in specific tests. On the other hand, melatonin seems to have improved balance and long-term continuous exercise performance, at least in nonathletes. More investigations are required to corroborate these findings.

Impact of Melatonin Supplementation on Sports Performance and Circulating Biomarkers in Highly Trained Athletes: A Systematic Review of Randomized Controlled Trials

“…However, no direct relationship between melatonin supplementation and sports performance has been described [31,70]. In this way, melatonin produced a decrease in strength and power [31]. This could be due to the depressive effects of this hormone on the central nervous system or to hypoglycemia reported in other studies [42,43].…”

“…Also, melatonin supplementation increases glucose in the muscle, improves lipid profile (evidenced by significant decrease in total cholesterol [38,52] and triglycerides [53]), and reduces body mass, contributing to better adaptation to demanding efforts [70]. However, no direct relationship between melatonin supplementation and sports performance has been described [31,70]. In this way, melatonin produced a decrease in strength and power [31].…”

“…Melatonin did not improve strength, power, speed, and short-duration continuous exercise in trained athletes. However, an improvement in balance and performance of long-term continuous exercise was reported in non-athletes [31]. For this reason, this systematic review will aim to identify, evaluate, analyze, and summarize the findings of relevant original studies regarding the effects of melatonin administration on several parameters, including: circulating biomarkers (blood glucose, lipid metabolism, kidney function, liver function, hormone response, inflammatory response, and muscle damage), antioxidant status (antioxidant enzymes, oxidative stress biomarkers, antioxidant function and glutathione homeostasis), perceptual and cognitive response, physiological biomarkers, melatonin bioavailability, adverse effects of melatonin, and sports performance (long-term continuous exercise, aerobic capacity, strength, and power) in highly trained athletes.…”

“…Therefore, the physiological effects of melatonin supplementation could be advantageous for restoration of certain health biomarkers and recovery after certain demanding physical actions. However, a recent systematic review [31] did not clarify whether there is an effect of melatonin administration on physical performance. Melatonin did not improve strength, power, speed, and short-duration continuous exercise in trained athletes.…”