Effect of modality on cardiopulmonary exercise testing in male and female COPD patients

•We compared the cardiorespiratory responses to exercise testing in COPD patients.•Physiological responses between treadmill and cycle CPET were similar.•Physiological responses were similar between sexes.•Either modality can be used when testing mild/moderate COPD patients.

The purpose of this study was to examine the physiological responses to treadmill and cycle cardiopulmonary exercise testing (CPET) in male and female COPD patients. Fifty-five patients [28 males (FEV1 = 58.2 ± 19.5% predicted), and 27 females (FEV1 = 65.3 ± 16.6% predicted)] completed a treadmill and a cycle CPET in random order on two separate days. Respiratory and cardiovascular data were obtained. Compared to the cycle CPET, the treadmill elicited greater peak power output and peak oxygen uptake, while arterial saturation at peak exercise was lower with the treadmill; however, there were no differences between the responses in men and women. No differences were observed in heart rate, ventilation, tidal volume/breathing frequency, inspiratory capacity, or dyspnea responses between modalities or sex. The physiological responses between treadmill and cycle CPET protocols are largely similar for both men and women with COPD, indicating that either modality can be used in mild/moderate COPD patients.