Agreement, reliability, predictors and classification proposal of a 15-time trial test to assess critical power in amateur swimmers

This study aimed to explore the agreement and reliability of a 15 '-time trial test (T315 ') to assess critical power in a large cohort of amateur swimmers. An observational retrospective cohort study total of 2212 amateur swimmers were made evaluating the results of anthropometry, cardiovascular and functional fitness assessments. Also, the participants performed a front crawl swimming 15 ' all-out test to assess critical power. The Kolmogorov-Smirnov, t-test, regression, percentiles, intraclass correlation coefficient and Cohen's d effect size were developed using a statistical software A T315 ' categorization proposal was made based on sex and age. There were differences by sex in all anthropometric, functional, physiological and T315 ' outcomes. The T315 ' swimming test obtained almost perfect reliability in the distance based on intraclass correlation values and linear correlation coefficients. A bias of T315 ' of 2% was found, which represented a total of 10.65m between tests. T315 ' is a useful test to assess critical power as a baseline fitness reference value for programming swimming exercises in amateurs.