The effect of exercise training on the quality of sleep in national-level adolescent finswimmers

BACKGROUND: The purpose of the present study was to investigate whether the quality of sleep, in 91 national-level adolescent finswimmers, is affected by swimming style, swimming distance, and gender. METHODS: Twenty-four hours before the opening of the National Championship, the participants recorded the training characteristics and answered the following two questionnaires: Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Score. Athletes were allocated to groups by gender, swimming style (monofin vs. bifin) and swimming distance (≤ 200 m vs. > 200 m). The dependencies between qualitative variables were estimated by chi-square test or Cramer’s V test with modification by Fisher’s exact test with cell frequencies less than 5. Binary logistic regression was used in the multi-factor model. RESULTS: There was a difference in the variables of PSQI “usual getting up time” and “have pain during sleep” between the two swimming distance groups (≤ 200 m vs. > 200 m). By using a multi-factor model (χ(2) = 13.541, p = 0.035), the variables of PSQI “usual getting up time” and “have pain during sleep” remained independent predictors of the swimming distance (p = 0.019, OR 1.75, 95% CI 1.09–2.81). CONCLUSION: The athletes swimming distances > 200 m experience more episodes of pain during sleep and get up earlier than athletes swimming shorter distances.