The Effects of the Removal of Electronic Devices for 48 hours on Sleep in Elite Judo Athletes

December 15, 2017

Authors: Ian C Dunican 1, David T Martin, Shona L Halson, Reid J Reale, Brian T Dawson, John A Caldwell, Maddison J Jones, Peter R Eastwood

Journal: Journal of Strength and Conditioning Research

DOI: 10.1519/JSC.0000000000001697

Year Published: 2017


This study examined the effects of the removal of electronic devices (i.e., smartphones, etc.) for 48 hours on sleep quality and next-day athletic and cognitive performance in elite Judo athletes.


Over 6 days and nights, 23 eliteAustralian Judo athletes were monitored while attending a camp at the Australian Institute of Sport (AIS). In 14 athletes all electronic devices were removed on days 3 & 4 (i.e. for 48 hours: the ‘device-restricted group’) while 9 were permitted to use their devices throughout the camp (the ‘control group’).


Athletes wore an activity monitor (Readiband) continuously to provide measures of sleep quantity and quality. Other self-reported (diary) measures included time in bed, electronic device use, and rate of perceived exertion during training periods. Cognitive performance (Cogstate) and physical performance (single leg-triple hop test) were also measured.


When considering Night 2 as a ‘baseline’ for each group, removal of electronic devices on Nights 3 & 4 (device-restricted group) did not significantly change any sleep-related measure between the groups. When comparing actigraphy-based measures of sleep to subjective measures, all athletes significantly overestimated sleep duration by 58±85 minutes (p=0.001) per night and underestimated time of sleep onset by 37±72 minutes (p=0.001) per night. No differences in physical or cognitive function were observed between the groups.


This study has shown that the removal of electronic devices for a period of 48 hours two nights during a judo camp does not affect sleep quality or quantity or influence athletic or cognitive performance.

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