One session of interval work does not alter VO2max, peak power or plasma volume

We examined the effect of one high-intensity cycling workout on aerobic capacity (VO2max), peak cycling power, and estimated change in plasma volume on subsequent days. Eight healthy males (age=29.5 +/- 5.3 years, height=1.81 +/- 0.09 m, mass=81.5 +/- 7.5 kg) visited the laboratory on three occasions. The first visit (D1) included baseline measures of cycling VO2max, haematocrit, and haemoglobin. Following a brief rest, the participants performed a high-intensity cycling workout of six 30-s cycling intervals (modelled on the Wingate cycle test) with each repetition separated by 3 min rest. The final two visits (D2 and D3) included identical measures as the first visit and occurred 48 and 96 h after the interval workout. No significant differences were found for VO2max (53.4 +/- 5.3, 53.7 +/- 6.7, and 53.7 +/- 6.2 ml center dot kg-1 center dot min-1), peak power (386 +/- 35, 384 +/- 35, and 389 +/- 35 W) or estimated change in plasma volume [-0.8 +/- 8.5% (D1-D2), 1.5 +/- 11.5% (D2-D3), and -1.6 +/- 9.6% (D1-D3)] between any of the three test days. Our results show that one short-term high-intensity cycling workout does not alter VO2max, peak power or estimated change in plasma volume on subsequent days, and is therefore unlikely to benefit or hinder performance.