The influence of active and passive smoking on the cardiorespiratory fitness of adults

Background: The aim of this study was to analyze the influence of active and passive smoking on cardiorespiratory responses in asymptomatic adults during a sub-maximal-exertion incremental test. Methods: The participants (n = 43) were divided into three different groups: active smokers (n = 14; aged 36.5 +/- 8 years), passive smokers (n = 14; aged 34.6 +/- 11.9 years) and non-smokers (n = 15; aged 30 +/- 8.1 years). They all answered the Test for Nicotine Dependence and underwent anthropometric evaluation, spirometry and ergospirometry according to the Bruce Treadmill Protocol. Results: VO2max differed statistically between active and non-smokers groups (p < 0.001) and between non-smokers and passive group (p=0.022). However, there was no difference between the passive and active smokers groups (p=0.053). Negative and significant correlations occurred between VO2max and age (r = -0.401, p = 0.044), percentage of body fat (r = -0.429, p = 0.011), and waist circumference (WC) (r = -0.382, p = 0.025). Conclusion: VO2max was significantly higher in non-smokers compared to active smokers and passive smokers. However, the VO2max of passive smokers did not differ from active smokers.