Effects of priming and pacing strategy on VO2 kinetics and cycling performance

Abstract

Purpose: To assess whether combining prior ‘priming’ exercise with an all-out pacing strategy was more effective at improving O2 uptake (VO2) kinetics and cycling performance than either intervention administered independently. Methods: Nine males completed target-work cycling performance trials using a self-paced or all-out pacing strategy with or without prior severe-intensity (70%Δ) priming exercise. Breath-by-breath pulmonary VO2 and cycling power output were measured during all trials. Results: Compared to the self-paced-unprimed control trial (22 ± 5 s), the VO2 mean response time (MRT) was shorter (VO2 kinetics was faster) with all-out pacing (17 ± 4 s) and priming (17 ± 3 s), with the lowest VO2 MRT observed when all-out pacing and priming were combined (15 ± 4 s) (P<0.05). However, total O2 consumed and end-exercise VO2 were only higher than the control condition in the primed trials (P<0.05). Similarly, cycling performance was improved compared to control (98 ± 11 s) in the self-paced-primed (93 ± 8 s) and all-out-primed (92 ± 8 s) trials (P<0.05), but not the all-out-unprimed trial (97 ± 5 s; P>0.05). Conclusions: These findings suggest that combining an all-out start with severe-intensity priming exercise additively improves the VO2 MRT, but not total O2 consumption and cycling performance since these were improved by a similar magnitude in both primed trials relative to the self-paced-unprimed control condition. Therefore, these results support the use of priming exercise as a pre-competition intervention to improve oxidative metabolism and performance during short-duration high-intensity cycling exercise, independent of the pacing strategy adopted.