Sleep habits in Japanese athletes─Results from actigraphic measurements─

Abstract

The purpose of this report was to clarify sleep habits among elite Japanese athletes. Nocturnal sleep data recorded with wrist actigraphy from 111 Japanese athletes were analyzed. Time in bed, sleep latency, total sleep time and sleep efficiency were normally distributed, and were not different between male and female. Mean values and standard deviation of sleep parameters were 7 : 21±0 : 40 for time in bed, 11.4±7.5 min for sleep latency, 6 : 25±0 : 45 for total sleep time, and 87.1±5.2% for sleep efficiency. Four (3.6%) of 111 athletes showed sleep latencies equal to or longer than 30 min. Thirty-three (29.7%) showed total sleep duration less than 6 h. Thirty-four (30.6%) showed sleep efficiency lower than 85%. Overall, sleep latency and total sleep duration tended to be shorter, and sleep efficiency was a little bit higher than the values from foreign athletes in the previous report. To understand characteristics of individual sleep, the supplemental table with 5 divisions was created on each sleep parameter. However, it must be remembered that these tables are based on the sleep characteristics of Japanese athletes mentioned above.