title: Association of Longitudinal Changes of Physical Activity on Smoking Cessation Among Young Daily Smokers.
abstract: OBJECTIVE
  To our knowledge, no longitudinal epidemiological study among daily smokers has examined the effects of physical activity change/ trajectory on smoking cessation. The purpose of this study was to examine the longitudinal effects of changes in physical activity on smoking cessation among a national sample of young (16-24 y) daily smokers.
  
  
  METHODS
  Data from the 2003-2005 National Youth Smoking Cessation Survey were used (N = 1178). Using hierarchical agglomerative cluster analysis, 5 distinct self-reported physical activity trajectories over 3 time periods (baseline, 12-month, and 24-month follow-up) were observed, including stable low physical activity, decreasing physical activity, curvilinear physical activity, stable high physical activity, and increasing physical activity. Nicotine dependence (Heaviness of Smoking Index) and demographic parameters were assessed via survey.
  
  
  RESULTS
  With stable low physical activity (16.2% quit smoking) serving as the referent group, those in the stable high physical activity (24.8% quit smoking) group had 1.8 greater odds of not smoking at the 24-month follow-up period (odds ratio = 1.81; 95% confidence interval, 1.12-2.91) after adjusting for nicotine dependence, age, gender, race-ethnicity, and education.
  
  
  CONCLUSIONS
  Maintenance of regular physical activity among young daily smokers may help to facilitate smoking cessation.
authors.affiliation: Dept of Health, Exercise Science, and Recreation Management, University of Mississippi, University, MS.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Loprinzi
authors.forename: Jerome F
authors.initials: JF
authors.lastname: Walker
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D057566:Self Report; D012907:Smoking / Q000453:epidemiology / Q000523:psychology*; D016540:Smoking Cessation / Q000523:psychology*; D011795:Surveys and Questionnaires; D014029:Tobacco Use Disorder; D055815:Young Adult