Hemodynamic responses to 30-min cycling exercise at 70% VO2 max both in ambiant air and during chest-immersion

The aim of this study was to examine the influence of water immersion to the chest on cardio-vascular adaptation to exercise. Upright or sitting immersion causes an increase in central blood volume, but it remains controversial whether central blood volume remains elevated during dynamic exercise in water and facilitates cardiac adaptation, depending particularly on the intensity of exercise which can be matched for O2 consumption (metabolic range) or for mechanical intensity (work load). We have compared hemodynamic variables measured during two cycling exercises at the same mechanical intensity, performed both in ambiant air and during immersion up to the chest.