EPAP. EPAP was applied with a silicone face mask
loaded with a spring linear pressure resistor (Vital Signs
USA, Totowa, New Jersey) in a unidirectional expiratory
valve (Fig. 2). The device was placed on the subject’s face
and held in place with straps around the head. At the time
of evaluation, the participants first spent some time to get
used to the EPAP mask (EPAP desensitization time). Thereafter,
the resistor was adjusted to perform a load around
5–10 cm H2O, based on previous studies that used these
values and encountered some clinical benefits in COPD
patients during exercise.