Cardiopulmonary Exercise Testing (CPX)
The CPX was performed on an electromagnetic cycle ergometer (Medfit
400L, Medical Fitness Equipment, Maarn, Netherlands), following a ramp
protocol, with a speed of 60 revolutions per minute (rpm) and workload
increments from 10w to 20w per minute, until achieving physical
exhaustion. Participants were connected to a valve and trachea system
(Vmax Spectra Series, SensorMedics Corp, Yorba Linda, CA, USA) where
pulmonary ventilation (PV), O2 and CO2concentrations were measured with calculation of oxygen consumption
(VO2) and CO2 production. When the
patient achieved exhaustion, the anaerobic threshold (AT) and
respiratory compensation point (RCP) were determined, both used to
prescribe the intensity of physical training.