Do Long-Haul Travel and Jet Lag Affect Athletes' Physiological, Humoral and Performance Outcomes? A Systematic Narrative Review.
Level 1 - systematic review of randomized trials
Systematic review synthesizing 89 studies following PRISMA guidelines.
PubMed 41893584 · doi:10.3390/sports14030093
What was done
A systematic narrative review following PRISMA 2020 guidelines searched PubMed, Scopus, and Web of Science for studies evaluating jet lag, travel fatigue, and long-haul travel in athletes of any sex or competition level. Eligible studies assessed physiological, hemodynamic, or performance outcomes across eastward or westward travel crossing 1 to 12 time zones. Data were synthesized from 89 included studies (selected from 284 identified records), including 17 studies evaluating mitigation interventions such as melatonin, caffeine, and light exposure.
What was found
Physiological alterations reported across the literature included sleep disturbances (n = 36 studies), body temperature changes (n = 18), hormonal shifts (n = 9), heart rate variability alterations (n = 4), and immune shifts (n = 4). Documented travel effects comprised subjective fatigue (n = 25), sleep disruption (n = 21), physical performance decrements (n = 18), mood disturbances (n = 15), and cognitive impairment (n = 9). Evaluated physical metrics included anaerobic power (n = 18), strength (n = 14), velocity (n = 12), aerobic capacity (n = 10), coordination (n = 8), and reaction time (n = 7). Study quality assessment revealed low risk of bias in 49%, moderate in 17%, and high in 34% of included studies. Eastward travel was predominantly associated with circadian desynchrony and reductions in aerobic capacity and coordination, while westward travel was primarily linked to fatigue and adverse team-sport outcomes.
Why it matters
This review maps the multi-system effects of long-distance travel on athletes, delineating how flight direction influences specific performance decrements and framing the evidence base for targeted mitigation strategies.
Limits
The review provides a narrative synthesis without meta-analytic pooling of effect sizes across heterogeneous sports and protocols. Over one-third (34%) of the underlying literature carried a high risk of bias, and only 17 of the 89 studies formally tested mitigation interventions.
Cited by
- supports The circadian literature indicates that it takes about an hour per day to adjust to time zone shifts, adjusting faster when traveling west than east.