The effects of passive inhalation of cigarette smoke on exercise performance.

The purpose of this investigation was to evaluate the effect of passive smoke inhalation on submaximal and maximal exercise performance. Eight female subjects ran on a motor driven treadmill for 20 min at 70% VO2max followed by an incremental change in grade until maximal work capacity was obtained. Each subject completed the exercise trial with and without the presence of residual cigarette smoke. Compared to the smokeless trials, the passive inhalation of smoke significantly reduced maximal oxygen uptake by 0.25 l X min-1 and time to exhaustion by 2.1 min. The presence of sidestream smoke also elevated maximal R value (1.01 vs 0.93), maximal blood lactate (6.8 vs 5.5 mM), and ratings of perceived exertion (17.4 vs 16.5 units). Passive inhalation of smoke during submaximal exercise significantly elevated the CO2 output (1.68 vs 1.58 l X min-1), R values (0.91 vs 0.86), heart rate (178 vs 172 bts X min-1) and rating of perceived exertion (13.8 vs 11.8 units). These findings suggest that passive inhalation of sidestream smoke adversely affects exercise performance.