Sleep, chronotype, and jet lag in athletic performance: a narrative review

Abstract

Background: The circadian timing system governs near-24-hour rhythms in body temperature, hormone secretion, and neuromuscular function that shape athletes' capacity to train, recover, and compete. Sleep, chronotype, and transmeridian travel are three interrelated circadian domains with direct medical relevance for performance. Aim: To critically appraise current evidence on how sleep quantity and quality, chronotype, and jet lag influence physical and cognitive performance in athletes, and to review countermeasures. Material and methods: Narrative review of experimental studies, systematic reviews, and meta-analyses addressing sleep, circadian rhythms, chronotype, and travel in athletic populations. Results: Athletes habitually sleep under 8 hours per night with reduced efficiency, and 28–65% screen as poor sleepers. Acute sleep loss degrades physical performance by approximately 7.6%, with afternoon and evening tasks most affected. Chronotype shifts the diurnal performance curve: morning types perform best early and evening types later, while late chronotypes may vary by up to 26% across the day. Time since entrained awakening predicts peak performance more reliably than clock time. Athletes report higher perceived exertion when training against their circadian preference. Social jetlag and eastward transmeridian travel impair strength, power, and aerobic capacity and raise injury risk. Sleep extension, strategic napping, light management, and melatonin partially offset these deficits. Conclusions: Sleep and circadian alignment are modifiable determinants of performance and health. Chronotype-informed scheduling and structured sleep and travel protocols should be integrated into athlete care, though heterogeneous methods limit firm conclusions.