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

Dunican, Ian C.1; Martin, David T.4; Halson, Shona L.4; Reale, Reid J.2,4; Dawson, Brian T.3; Caldwell, John A.5; Jones, Maddison J.3; Eastwood, Peter R.1

Journal of Strength and Conditioning Research: October 2017 - Volume 31 - Issue 10 - p 2832–2839
doi: 10.1519/JSC.0000000000001697
Original Research

Dunican, IC, Martin, DT, Halson, SL, Reale, RJ, Dawson, BT, Caldwell, JA, Jones, MJ, and Eastwood, PR. The effects of the removal of electronic devices for 48 hours on sleep in elite judo athletes. J Strength Cond Res 31(10): 2832–2839, 2017—This study examined the effects of evening use of electronic devices (i.e., smartphones, etc.) on sleep quality and next-day athletic and cognitive performance in elite judo athletes. Over 6 consecutive days and nights, 23 elite Australian 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 and 4 (i.e., for 48 hours: the “device-restricted group”), whereas 9 were permitted to use their devices throughout the camp (the “control group”). All 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 and 4 (device-restricted group) resulted in no significant differences in 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. Conclusion: This study has shown that the removal of electronic devices for a period of two nights (48 hours) during a judo camp does not affect sleep quality or quantity or influence athletic or cognitive performance.

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1Center for Sleep Science, School of Anatomy, Physiology and Human Biology, The University of Western Australia, Australia;

2University of Sunshine Coast, Sippy Downs, Queensland, Australia;

3School of Sports Science Exercise and Health, The University of Western Australia, Perth, Australia;

4Combat Sports Center, The Australian Institute of Sport, Canberra, Australian Capital Territory, Australia; and

5Coastal Performance Consulting, Key West, Florida

Address correspondence to Ian C. Dunican,

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Copyright © 2017 by the National Strength & Conditioning Association.