title: Predictors of adoption and maintenance of vigorous physical activity in men and women.
abstract: BACKGROUND
  This study examined predictors of adoption and maintenance of vigorous physical activity over time in a sample of 1,719 randomly selected women and men.
  
  
  METHODS
  Based on reported frequency of vigorous exercise in a mail survey at baseline, subjects were classified as sedentary (zero sessions per week), intermediate (one to two sessions per week), or active (three or more sessions per week).
  
  
  RESULTS
  On the same survey subjects reported on 25 potential determinants of physical activity based on a comprehensive learning model. Twenty-four months later, 85% of subjects were resurveyed, and their physical activity levels were classified. Within each baseline category and gender subgroup, predictors of follow-up physical activity were identified. In multivariate analyses, adoption of vigorous exercise by sedentary men was predicted by self-efficacy, age (inverse), and neighborhood environment (inverse). Adoption by sedentary women was predicted by education, self-efficacy, and friend and family support for exercise. Maintenance of vigorous physical activity was predicted by self-efficacy and age (inverse) for initially active men and by education for initially active women.
  
  
  CONCLUSIONS
  These results suggest that factors influencing adoption are different for men and women, and there may be different factors influencing adoption versus maintenance of vigorous physical activity.
authors.affiliation: Department of Psychology, San Diego State University, California 92182.
authors.forename: J F
authors.initials: JF
authors.lastname: Sallis
authors.forename: M F
authors.initials: MF
authors.lastname: Hovell
authors.forename: C R
authors.initials: CR
authors.lastname: Hofstetter
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D003625:Data Collection; D015444:Exercise; D005260:Female; D005500:Follow-Up Studies; D015438:Health Behavior; D006801:Humans; D008297:Male; D012737:Sex Factors