Time trials versus time-to-exhaustion tests: Effects on critical power, W0, and oxygen-uptake kinetics

Purpose: To investigate single-day time-to-exhaustion (TTE) and time-trial (TT) -based laboratory tests values of critical power (CP), W prime (W0), and respective oxygen-uptake-kinetic responses. Methods: Twelve cyclists performed a maximal ramp test followed by 3 TTE and 3 TT efforts interspersed by 60 min recovery between efforts. Oxygen uptake (VO 2) was measured during all trials. The mean response time was calculated as a description of the overall VO 2-kinetic response from the onset to 2 min of exercise. Results: TTE-determined CP was 279 ± 52 W, and TT-determined CP was 276 ± 50 W (P = .237). Values of W0 were 14.3 ± 3.4 kJ (TTE W0) and 16.5 ± 4.2 kJ (TT W0) (P = .028). While a hig…