Exercise facilitates smoking cessation indirectly via improvements in smoking-specific self-efficacy: Prospective cohort study among a national sample of young smokers.

Abstract

The purpose of this study was to examine whether exercise is associated with 2-year follow-up smoking status through its influence on smoking-specific self-efficacy. Longitudinal data from the 2003-2005 National Youth Smoking Cessation Survey were used, including 1,228 participants (16-24 years). A questionnaire was used to examine baseline exercise levels, baseline smoking-specific self-efficacy, follow-up smoking status, and the covariates. Baseline exercise was associated with baseline self-efficacy (β=0.04, p<0.001) after adjusting for age category, sex, race-ethnicity, education, and nicotine dependence. Baseline self-efficacy, in turn, was associated with 2-year smoking status (β=0.23, p<0.001) after adjustments. There was no adjusted direct effect of baseline exercise on 2-year smoking status (β=0.001, p=0.95); however, the adjusted indirect effect of baseline self-efficacy on the relationship between exercise and 2-year smoking status was significant (β=0.008, bootstrapped lower and upper CI: 0.002-0.02; p<0.05). The mediation ratio was 0.837, which indicates that smoking-specific self-efficacy mediates 84% of the total effect of exercise on smoking status. Among daily smokers, exercise may help to facilitate smoking cessation via exercise-induced increases in smoking-specific self-efficacy.