Intervention for Reducing Sleep Disturbances After a 12-Time Zone Transition.

Area of Science:

• Sports Science
• Sleep Medicine
• Human Physiology

Background:

• Jet lag, or desynchronosis, significantly disrupts sleep patterns and performance after rapid, long-distance travel across multiple time zones.
• Athletes and travelers undertaking transmeridian journeys often experience sleep disturbances, impacting physical and cognitive function.
• Effective countermeasures are crucial for mitigating the negative effects of jet lag on performance and well-being.

Purpose of the Study:

• To evaluate the efficacy of a pre-flight intervention aimed at reducing sleep disturbances following a 12-time zone transition.
• To compare the sleep onset latency and sleep efficiency of an experimental group receiving the intervention against a control group.

Main Methods:

• Participants traveled from Tokyo to Rio, with the experimental group undergoing bright light exposure at night and gradual sleep schedule delays for 4 days pre-flight.
• The experimental group also received 8 mg of ramelteon daily for 5 days, starting on their first flight day.
• Sleep onset latencies and sleep efficiency were measured using wristwatch actigraphy, and subjective morning tiredness was assessed.

Main Results:

• The experimental group exhibited significantly shorter sleep onset latencies (7.7 ± 2.5 min) compared to the control group (16.3 ± 3.7 min) in Rio (p < 0.01, d = 0.89).
• Sleep efficiency in the experimental group was higher (88.5 ± 1.2%) during the first 3 nights in Rio than in the control group (82.9 ± 3.0%) (p < 0.01, d = 1.09).
• The intervention demonstrated a large effect size for both sleep onset latency and sleep efficiency.

Conclusions:

• The pre-flight intervention effectively reduced sleep disturbances and improved sleep quality after a 12-time zone transition.
• This multi-component strategy, including bright light, schedule shifting, and ramelteon, offers a viable method for mitigating jet lag.
• The findings suggest potential applications for athletic conditioning and performance optimization in events requiring significant time zone changes.