Perception of effort and respiratory sensitivity during exposure to ozone

Abstract

The purpose of this study was to examine the effects of exposure to the air pollutant ozone during exercise on perception of effort and to evaluate perceptual sensitivity to respiratory responses during this exposure. Fourteen male subjects were exposed to ozone concentrations of 000,030, and 0 50 p.p.m. during both resting and bicycle ergometer exercise treatments. Ratings of perceived exertion were obtained periodically during the 40min exercise period. Perceptual exponents were determined from magnitude estimation and production of lung volumes obtained before, at the approximate midpoint, and at the end of the 2 hour exposure period. Significant (p<0 01) decrements in FVC, FEV₁, and MEF_25-75 resulting from ozone exposure were greater immediately following an exercise bout. Perception of effort based on sensory input from above the waist (central) increased significantly (p<0 05) with increasing ozone concentrations. The increase in central perceived exertion appeared sooner in the exercise period and was of a greater magnitude during 0-50 p.p.m. ozone in comparison with overall perceived exertion and ratings localized to the exercising muscles. Perceptual exponents derived from magnitude estimates during the exercise treatment were significantly (p<0 05) higher than for the room air condition. It was concluded that perceptual responses to exercise and respiratory stimuli during ozone exposure reflected the decrements in pulmonary function observed with exposure to ozone.