Ba A.,Service des Explorations Fonctionnelles Respiratoires |
Ba A.,Cheikh Anta Diop University |
Bregeon F.,Service des Explorations Fonctionnelles Respiratoires |
Delliaux S.,Service des Explorations Fonctionnelles Respiratoires |
And 3 more authors.
BioMed Research International
Cardiopulmonary response to unloaded cycling may be related to higher workloads. This was assessed in male subjects: 18 healthy sedentary subjects (controls), 14 hypoxemic patients with chronic obstructive pulmonary disease (COPD), and 31 overweight individuals (twelve were hypoxemic). They underwent an incremental exercise up to the maximal oxygen uptake (VO2max), preceded by a 2 min unloaded cycling period. Oxygen uptake (VO2), heart rate (HR), minute ventilation (VE), and respiratory frequency (fR) were averaged every 10 s. At the end of unloaded cycling period, HR increase was significantly accentuated in COPD and hypoxemic overweight subjects (resp., +14±2 and +13±1.5 min-1, compared to +7.5±1.5 min-1 in normoxemic overweight subjects and +8±1.8 min-1 in controls). The fR increase was accentuated in all overweight subjects (hypoxemic: +4.5±0.8; normoxemic: +3.9±0.7 min-1) compared to controls (+2.5±0.8 min-1) and COPDs (+2.0±0.7 min-1). The plateau VE increase during unloaded cycling was positively correlated with VE values measured at the ventilatory threshold and VO2max. Measurement of ventilation during unloaded cycling may serve to predict the ventilatory performance of COPD patients and overweight subjects during an exercise rehabilitation program. © 2015 Abdoulaye Ba et al. Source