title: Measuring fatigue relative to peak power output during high-intensity cycle sprinting.
abstract: The purpose of this report was to introduce and validate a method to account for variable fatigue rates during cycle sprinting by incorporating decline from peak power (30%) as a test termination criterion. Fifteen healthy men performed three maximal sprint tests separated by 20 min (Bouts 1 and 2) and 48 hours (Bout 3). Power curves were analyzed for peak power, time to peak, time to fatigue (decline of 30% from peak), total work, total test time, fatigue rate, and the fatigue index. High test-retest reliability was demonstrated for all variables (R = 0.85-0.98). No significant differences were detected between variables (Bouts 1, 2 and 3; p > 0.01). Fatigue rates varied widely among participants (range = 24.7-65.4 W.s-1), but the fatigue index was consistent (31.1 +/- 0.16; mean +/- standard error of measurement, range = 30.1-32.5%). Our data show that variable fatigue responses among participants are normalized to the percentage of decline from peak power by incorporating a relative fatigue cutoff criterion. This approach might inform mechanisms relating to short-term fatigue and recovery during consecutive sprint bouts.
authors.affiliation: Department of Health and Kinesiology, Texas A&M University, USA. whcooke@gems.vcu.edu
authors.forename: W H
authors.initials: WH
authors.lastname: Cooke
authors.forename: C A
authors.initials: CA
authors.lastname: Whitacre
authors.forename: W S
authors.initials: WS
authors.lastname: Barnes
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology*; D003625:Data Collection; D016552:Ergometry / Q000379:methods; D005221:Fatigue / Q000503:physiopathology*; D006801:Humans; D008297:Male; D015203:Reproducibility of Results