Pulmonary function tests, including forced expiratory
maneuver parameters [forced vital capacity (FVC), force expiratory
volume in 1 s (FEV1), and peak expiratory flow (PEF)],
gas dilution lung volumes (total lung capacity, functional
residual capacity, and residual volume), inspiratory muscle
strength (PImax), and expiratory muscle strength (PEmax) measurements,
were performed by a spirometer (Messgeraete