Influence of Prior Exercise on VO2 Kinetics Subsequent Exhaustive Rowing Performance

Prior exercise has the potential to enhance subsequent performance by accelerating the oxygen uptake (VO2) kinetics. The present study investigated the effects of two different intensities of prior exercise on pulmonary VO2 kinetics and exercise time during subsequent exhaustive rowing exercise. It was hypothesized that in prior heavy, but not prior moderate exercise condition, overall VO2 kinetics would be faster and the VO2 primary amplitude would be higher, leading to longer exercise time at VO2max. Six subjects (mean +/- SD; age: 22.9 +/- 4.5 yr; height: 181.2 +/- 7.1 cm and body mass: 75.5 +/- 3.4 kg) completed square-wave transitions to 100% of VO2max from three different conditions: without prior exercise, with prior moderate and heavy exercise. VO2 was measured using a telemetric portable gas analyser (K4b(2), Cosmed, Rome, Italy) and the data were modelled using either mono or double exponential fittings. The use of prior moderate exercise resulted in a faster VO2 pulmonary kinetics response (tau(1) = 13.41 +/- 3.96 s), an improved performance in the time to exhaustion (238.8 +/- 50.2 s) and similar blood lactate concentrations ([La-]) values (11.8 +/- 1.7 mmol.L-1) compared to the condition without prior exercise (16.0 +/- 5.56 s, 215.3 +/- 60.1 s and 10.7 +/- 1.2 mmol.L-1, for tau(1), time sustained at VO2max and [La-], respectively). Performance of prior heavy exercise, although useful in accelerating the VO2 pulmonary kinetics response during a subsequent time to exhaustion exercise (tau(1) = 9.18 +/- 1.60 s), resulted in a shorter time sustained at VO2max (155.5 +/- 46.0 s), while [La-] was similar (13.5 +/- 1.7 mmol.L-1) compared to the other two conditions. Although both prior moderate and heavy exercise resulted in a faster pulmonary VO2 kinetics response, only prior moderate exercise lead to improved rowing performance.