Reproducibility of variables derived from a 90s all-out effort isokinetic cycling test

Aim. The aim of this study was to examine the reliability of the power output profile obtained from a 90 s all-out isokinetic cycling test. Methods. Within a 10 day period, 16 participants (-x±s: age 30.1±6.4 years; body mass 69.2±10.6 kg) performed an incremental VO2 max ramp test and two 90 s all-out efforts on an isokinetic cycle ergometer. Peak power (PP), mean power (MP), end power (EP) and fatigue index (FI) were determined. Results. There were no significant differences between tests for MP, EP and FI values (P>0.05) but PP was higher on the second test (P=0.003). Ratio limits of agreement suggested that a repeated measurement might be expected in 95% of cases to be between 0.92 to 1.21 times the initial PP measurement and 0.97 to 1.07 times the initial MP measurement. The 95% limits of agreement for EP and fatigue were -23 to +33 W (1.8±9.7% of the mean) and -6.5% to 8.8% (2±7.6% of the mean), respectively. Conclusions. The 90 s all-out test appears to be a reliable test for given aspects of the physiological profile, with the exception of PP.