Objective: To assess which exercise testing protocol is most sensitive for assessing peak oxygen uptake (VO2peak) changes as a result of cardiac rehabilitation.
Design: Prospective randomized clinical trial.
Setting: Outpatient cardiac rehabilitation center.
Participants: Forty-two cardiac patients (33 men; mean age, 65.4+/-8.4 y).
Intervention: All patients were included into a 7-week cardiac rehabilitation program and randomized in 2 subgroups. One group of patients was evaluated by a 1-minute stage (n=21) and another group by a 3-minute stage (n=21) exercise testing protocol.
Main outcome measures: In both groups, maximal cardiopulmonary exercise tests on a bicycle with analysis of VO2peak, expiratory volume (VE), respiratory exchange ratio, heart rate, cycling resistance (W), and test duration were performed at the start and end of the program.
Results: Subgroups were closely matched, and no changes in beta-blocker treatment occurred during this study. As result of the rehabilitation program, total test duration and Wpeak improved significantly in both groups (P<.05). Nonetheless, VO2peak and VEpeak increased significantly in the 1-minute stage duration group (P<.05) but not in the 3-minute stage duration group (P>.05). In addition, the change of VO2peak, VEpeak, and total test duration was significantly greater in the 1-minute stage duration group compared with the 3-minute stage duration group (P<.05).
Conclusions: For detecting changes of VO2peak as result of cardiac rehabilitation, a 1-minute stage exercise testing protocol is more sensitive when compared with a 3-minute stage exercise testing protocol.