A comparison between ventilation and heart rate as an indicator of oxygen uptake during physical activities of different intensities

International audienceThe aim of this study is to compare the relation between ventila-tion (VE) and oxygen uptake (VO2) [VO2=f (VE)] and between heart rate (HR) and VO2 [VO2=f (HR)]. Each one of the subjects performed three types of activities of different intensities (walk-ing without load, walking with load and intermittent work). VO2, VEand HR were measured continuously by using indirect calorimetry and an electrocardiogram. Linear regressions and coefficients of determination (râ²) were calculated to compare the relation VO2 = f (VE) and VO2 = f (HR) for two different regroupings: by session duration (râ²session) and by subject (râ²subject). Results showed that râ²session of the relation VO2 = f (VE) were significantly higher than those of the relation VO2 = f (HR) for steady state activities (walking with or without load during 3 or 6 min,