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Published on: August 8, 2019
Sleep Duration, Sleep Timing, and Self-Reported Wellbeing in Collegiate Women Volleyball Athletes: A Prospective
Jesse D Cook1, Jennifer L Sanfilippo2, Jessica J Love1,3
1University of Wisconsin - Madison, School of Medicine and Public Health, Department of Psychiatry, Madison, Wisconsin.
Background:
Previous research assessing sleep health in collegiate athletes has relied predominantly upon self-report measures. This investigation leveraged a modern, consumer-grade wearable device to examine sleep duration (SD) and timing across a 5-month window, including both preseason and in-season periods, in a sample of female National Collegiate Athletic Association (NCAA) Division I volleyball athletes.
Hypothesis:
Shorter SD and earlier waketimes would associate with worse self-reported wellbeing (mood, muscle recovery, and energy). SD would be shorter and waketimes would be earlier during preseason, relative to in-season, as well as on weekdays, relative to weekends.
Study Design:
Prospective cohort study.
Level Of Evidence:
Level 3.
Methods:
Data from female NCAA Division I volleyball athletes were collected across a 5-month window. Oura ring measured SD, bedtimes, and waketimes, with wellbeing ratings self-reported each morning. An analytic dataset of 1361 sleep nights from 13 athletes was constructed. Mixed-effects models examined relationships between sleep and wellbeing variables, as well as differences in these variables between preseason versus in-season and weekdays versus weekends.
Results:
Shorter SD and earlier waketimes were associated significantly with lower self-reported mood and energy. SD was significantly longer in-season, relative to preseason (6.98 ± 0.13 hours) (7.42 ± 0.09 vs 6.98 ± 0.12 hours, P < 0.01). Waketimes were significantly later in-season, relative to preseason (08:20 ± 00:08 vs 07:03 ± 00:05, P < 0.01), and significantly later on weekends, relative to weekdays (08:18 ± 00:08 vs 07:37 ± 00:07, P < 0.01). The shortest SD (6.91 ± 0.13 hours) and earliest waketimes (06:44 ± 00:05) occurred on weekdays during preseason.
Conclusion:
Short SD and early waketimes were associated with lower self-reported mood and energy in collegiate volleyball athletes. Athletes were most vulnerable to insufficient SD on weekdays during the preseason, seemingly as a consequence of earlier waketimes.
Clinical Relevance:
Interventions to facilitate later waketimes, such as delaying early morning training times, may be useful for supporting athlete sleep health and wellbeing.
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