ESTIMATION OF SLEEP QUALITY IN COLLEGIATE CROSS-COUNTRY SKIERS USING WRIST-WORN ACTIVITY MONITORS AND STANDARDIZED SURVEYS
Poor sleep quality and nightly sleep duration are associated with increased stress and an increased risk for many chronic health problems. For collegiate students-athletes, who experience considerable academic and training stressors, poor sleep quality may also influence academic and performance abilities. PURPOSE: the primary purpose of this study was to evaluate the relationships between several measures of sleep quality within collegiate cross-country (XC) skiers throughout a semester. METHODS: Fifteen XC skiers (10 women, 20±2 yrs, 22.9±2.3 kg/m2 BMI, 50.8±4.2 ml/kg/min VO2MAX; 5 men, 21±1 yrs, 22.5±1.2 kg/m2 BMI, 62.4±1.7 ml/kg/min VO2MAX) from the Montana State University (MSU) Nordic Ski Team were recruited. Each month from September to December, 2014, subjects used a wrist-worn activity monitor (AW) for seven consecutive nights, while self-reported sleep and training logs and on-line surveys were completed at select times each month. Total sleep time (TST) and sleep efficiency (SE) were calculated from the AW, whereas the Pittsburgh Sleep Quality Index (PSQI) and Epsworth Sleepiness Scale questionnaire (ESS) were used to assess sleep quality and daytime sleepiness, respectively. Differences in TST, SE, PSQI, ESS and hours of training recorded in the training logs (TL, hrs) throughout the four measurement trials (T1, T2, T3, T4) were evaluated using two-factor repeated measures ANOVA and Tukey’s HSD post-hoc test (0.05 alpha). The Pearson correlation was also used to examine relationships between TST, SE, PSQI, ESS and TL. RESULTS: TST for T1 was less than that for T2 or T3 (T1 = 7.7 hrs/night; T2 and T3 = 8.1 hrs/night; P4, 7.9 hrs/night, was not significantly different from the other TST measures. ESS increased steadily (T1 < T2 < T3 < T4; P1 > T4 > T3 > T2; PP = 0.04) and ESS (R = +0.40, P = 0.002). CONCLUSIONS: Poor sleep quality, as indicated by higher PSQI values, may have led to increased nightly sleep duration and daytime sleepiness. These findings also provide preliminary evidence that training volume may serve as a moderator that tends to cause elevated TST, and thus ameliorate PSQI, ESS, and SE.
Zhu, W; Hultin, L; Wheeler, J L.; and Heil, D P.
"ESTIMATION OF SLEEP QUALITY IN COLLEGIATE CROSS-COUNTRY SKIERS USING WRIST-WORN ACTIVITY MONITORS AND STANDARDIZED SURVEYS,"
International Journal of Exercise Science: Conference Proceedings: Vol. 8:
3, Article 57.
Available at: https://digitalcommons.wku.edu/ijesab/vol8/iss3/57