Pulmonary Function at Rest and during Exercise in Uncomplicated Obesity

Abstract

Nine lean (6.9%–19.3% body fat) and 12 moderately obese (31.6%–42.3% body fat) college men were compared in terms of maximum aerobic power, resting pulmonary function tests, and selected respiratory variables during a progressive bicycle ergometer test. The Vdot]O₂ max (1/min) was slightly higher (p > .05) in the obese group but significantly lower (p < .05) when expressed in cc/kg min or cc/kg FFBW min. Lower RV, ERV, and FRC data were observed in the obese group, but no differences were documented for tests of FVC or MVV. Higher values were displayed by the obese subjects for Vdot]E, Vdot]A, and tidal volume at rest and during each submaximal intensity of bicycle work. These observations appeared to be due to the obese subjects' higher energy expenditures, since no differences were documented in the ventilation equivalent (Vdot]E/Vdot]O₂), the Vdot]A/Vdot]E ratio, or breathing frequency. It was concluded, within the limitations of the study, that the hypothesis of respiratory dysfunction in the moderately obese was not supported.