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 VO_2max. 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 VO_2max from three different conditions: without prior exercise, with prior moderate and heavy exercise. VO₂ was measured using a telemetric portable gas analyser (K4b², 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 (τ₁ = 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 τ₁, time sustained at VO_2max and La⁻], respectively). Performance of prior heavy exercise, although useful in accelerating the VO₂ pulmonary kinetics response during a subsequent time to exhaustion exercise (τ₁ = 9.18±1.60 s), resulted in a shorter time sustained at VO_2max (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.