Oxygen Kinetics at the on and offset of exercise has had researchers puzzling for decades. In practical application such as in vivo tests using a metabolic cart or VO2 analyzer, only whole body pulmonary oxygen uptake (pVO2) is accessible. Pulmonary VO2 is influence not only by muscle VO2 but also by cardiac output, blood volume, oxygenation amongst other factors. The aim of this project is to build and validate a model that discloses those factors influencing pVO2 in a quantitaive way, hence open a clearer view on pVO2 data.

Experiments

Twelve healthy trained males were recruited for this project. Each of them underwent a series of load tests on a cycling ergometer (SRM high performance ergometer, 20 strain gauges powermeter version, SRM GmbH, Juelich, Germany): 1) A series of three sub-maximum efforts including pre and post efforts lactate measurements. 2) An all out seated sprint test; including pre and post efforts lactate measurements. 3) A ramp test until exhaustion, including pre and post efforts lactate measurements as well as measuring of breath by breath gas exchange. During each test power, heart rate and cadence is recorded with 1Hz.

This data is used to create a metabolic profile in INSCYD (VLamax, VO2max, MLSS, MMSS, lactate production and combustion kinetics, etc.)

Afterwards each subject undergoes three different interval trainings, on three different days in randomised order: after sufficient warm up the subjects undergo a HIT training, consisting of 4×30 at 150% of VO2max. Each on-phase is seperated by 4min recovery, using different recovery modes: 0% VO2max (=passive rest), 35% VO2max, 55% VO2max.

Power, heart rate, cadence and muscle oxygenation are recorded with 1Hz. Pulmonary gas exchange is recorded breath-by breath.