Time-of-Day Effects on Static and Dynamic Balance in Elite Junior Athletes and Untrained Adolescents

The aim of the present study was to analyse the daily variation of balance in two groups of female adolescents: elite athletes (n=20, aged 13.2 ± 0.5 years) and untrained students (n=20, aged 12.9 ± 0.6 years). Participants underwent two testing sessions over two days at two different times each day. Morningness-Eveningness self-assessment questionnaire was administered to assess the chronotype of the participants and oral temperature was measured too. Significant group differences were found in the overall balance tests (p<0.01). Athlete group showed no significant differences in balance tests with respect to the time-of-day. Untrained adolescents attained better results in the morning in the dynamic balance tests (p<0.01). No correlations were found between chronotype, oral temperature variations and balance tests scores. The main outcome of the study was that elite athletes did not show time-of-day effects on balance, whereas the untrained adolescents achieved better results in the morning.