Competition-Related alterations in nighttime sleep and heart rate metrics: A longitudinal study in NCAA division 1 women's volleyball athletes

Research has shown that competition can affect the sleep health of athletes; however, female collegiate athletes have been underrepresented and understudied. This investigation examined competition-related alterations in nighttime sleep and heart rate (HR) metrics among National Collegiate Athletic Association (NCAA) Division 1 women's volleyball athletes, leveraging objective data collected longitudinally across a four-month calendar season. Oura ring measured nighttime sleep and HR metrics. Sleep episodes were classified based on competition status (no match [NM], night before [NB], or night following [NF]). Linear mixed-effects models examined differences in sleep and HR between NM, NB, and NF, with post hoc comparisons conducted when appropriate. Secondary analyses explored the influence of match timing (afternoon vs. evening) and location (home vs. away) on NB and NF outcomes. 656 nighttime sleep episodes from 10 athletes were analyzed, including data spanning 22 matches. NF sleep was significantly shorter and delayed, relative to NM and NB, with significantly increased HR and decreased HR variability. NB sleep duration was significantly longer than NM. Neither sleep onset latency nor sleep efficiency significantly differed between conditions. In secondary analyses, athletes were vulnerable to shorter sleep duration prior to afternoon matches and those played at home, and following evening matches and those played on the road. NCAA Division 1 women's volleyball athletes were vulnerable to shorter and delayed nighttime sleep following competition, with alterations in HR metrics possibly capturing the physiological toil of competition. Athletes showed extended nighttime sleep before competition, perhaps reflecting an intentional prioritization of sleep to enhance performance.