Abstract
Introduction: In cardiopulmonary rehabilitation programs (CPR), constant-load cycle endurance tests (CLET) protocols are used to evaluate the response to specific interventions. In healthy subjects CLET protocols show a much lower reproducibility than time trial test (TTT) protocols. The purpose of this study was to evaluate the reproducibility of the CLET protocol and TTT protocol on a cycle ergometer in patients with COPD.
Methods: In 20 patients with COPD (GOLD II-IV, FEV1 of 56±15%) exercise performance was measured. Patients were randomly allocated to a CLET protocol or TTT protocol. Patients performed the test protocol to which they were assigned, five times. Patients in the CLET group exercised to exhaustion at 120% of the actual individual training workload attained in the during CPR training sessions. Patients in the TTT group were asked to perform a certain amount of work (120% * Wtraining * 420) as fast as possible.
Results: TTT protocol showed a significantly lower coefficient of variation (CV) (6.6±3.6) than the CLET protocol (22.2±9.8) (P <.001). Individual CV (time to completion) ranged from 9.0% to 36,9% in the CWRT protocol and from 3,4% to 16,3% in the TTT protocol. There was a significant difference between the mean exercise time of the CLET (591±185 s) and the TTT (367±122 s) (P <.005). There were no differences in mean work (p =.058), power (p =.463), RPM (p =.629), subjective assessments of breathlessness (P =.55) and leg fatigue (P =.15) between the CLET and de TTT protocol.
Conclusions: The TTT protocol reproducibility was sign. higher than in the CLET protocol in patients with moderate-to-severe COPD.
- © 2011 ERS
