Fast-Start Strategy Improves (V)over dotO2 Kinetics and High-Intensity Exercise Performance

BAILEY, S. J., A. VANHATALO, F. J. DIMENNA, D. P. WILKERSON, and A. M. JONES. Fast-Start Strategy Improves (V) over dotO(2) Kinetics and High-Intensity Exercise Performance. Med. Sci. Sports Exerc., Vol. 43, No. 3, pp. 457-467, 2011. Purpose: The purpose of this study was to investigate the influence of pacing strategy on pulmonary (V) over dotO(2) kinetics and performance during high-intensity exercise. Methods: Seven males completed 3- and 6-min bouts of cycle exercise on three occasions with the bouts initiated using an even-start (ES; constant work rate), fast-start (FS), or slow-start (SS) pacing strategy. In all conditions, subjects completed an all-out sprint over the final 60 s of the test as a measure of performance. Results: For the 3-min exercise bouts, the mean response time (MRT) for the (V) over dot(O2) kinetics over the pacing phase was shortest in FS (35 +/- 6 s), longest in SS (55 +/- 14 s), and intermediate in ES (41 +/- 10 s) (P < 0.05 for all comparisons). For the 6-min bouts, the (V) over dotO(2) MRT was longer in SS (56 T 15 s) than that in FS and ES (38 T 7 and 42 T 6 s, respectively, P < 0.05). The (V) over dotO(2) at the end of exercise was not different from the (V) over dot O-2max during the 6-min exercise bouts or 3-FS but was lower than (V) over dotO(2max) for 3-ES and 3-SS (P < 0.05). The end-sprint performance was significantly enhanced in 3-FS compared with 3-ES and 3-SS (mean power = 374 +/- 68 vs 348 +/- 61 and 345 +/- 71 W, respectively; P < 0.05). However, end-sprint performance was unaffected by pacing strategy in the 6-min bouts. Conclusions: These data indicate that an FS pacing strategy significantly improves performance during 3-min bouts of high-intensity exercise by speeding (V) over dotO(2) kinetics and enabling the attainment of (V) over dotO(2max).