Acute cardiorespiratory responses in participants with heart disease during cycling at different immersion levels

Summary Physical activity is often avoided or practised at a low‐intensity level because of the limited ability of patients with heart disease ( HD ) to provide sustained effort. Immersible training has been suggested as a possible alternative as hydrostatic pressure can modify some hemodynamic parameters in healthy patients and potentially increase the exercise capacity in patients with HD . The purpose of this study was to examine the acute cardiorespiratory adaptations at different levels of immersion using an immersible ergometer ( IE ) in patients with HD . Twenty‐one patients and 13 healthy controls ( HC ) participated in this study. Several cardiorespiratory parameters were assessed at two levels of immersion (hips and xiphoid) for five different pedalling rates (40, 50, 60, 70 and peak rpm). At submaximal intensity, HD and HC participants did not differ significantly for most variables. However, for nearly and/or maximal workload, HD participants showed significantly lower values for VO 2 and higher values for V E /VO 2 and V E /VCO 2 for both immersion levels. The increase in immersion level from hips to xiphoid resulted in a significant decrease in VO 2 in both HC and HD groups at the same exercise intensity. In addition, the increase in the effects of size values based on the exercise workload indicates that group differences are accentuated with the highest pedalling rates. Our data suggest that participants with HD may benefit from the hydrostatic effect during IE cycling by allowing them to alleviate their submaximal efforts and increasing their maximal cardiorespiratory capacity during hip immersion.