Respiratory gas exchanges, heart rate and blood lactate kinetics during and after the repetition of supramaximal individualized exercises in trained and untrained subjects

Objective.-Determine the kinetics of gas exchange, heart rate (HR) and blood lactate concentration [La] during and after supramaximal intermittent individualized exercises in trained (TR) and untrained (UTR) subjects. Methods.- 14 subjects (7 trained and 7 untrained subjects) performed three repetitions of an exercise corresponding to 60% of time to exhaustion at 120% of the aerobic maximum power on a cycle ergometer (MedGraphics/Excalibur, USA). The two first exercises were separated by 5 min recovery. The third exercise was followed by 20 min recovery. The oxygen uptake was measured continuously using a breath by breath device (Medgraphics/CPX). Blood was taken from fingers during recoveries for lactate analyzis. Results.- Results showed that oxygen uptake (VO sub(2) ml/minute, P