title: Recreational physical activity in postmenopausal women is stable over 8 years of follow-up.
abstract: BACKGROUND
  The goals of this study were to examine 1) longitudinal trajectories of energy expenditure from recreational physical activity (PA) in postmenopausal women, 2) whether women who belong to different PA trajectories engage in different types of PA, and 3) whether baseline sociodemographic, health, psychosocial, and lifestyle characteristics predict membership in PA trajectories.
  
  
  METHODS
  Women from the Women's Health Initiative Observational Study with baseline PA data (n = 92,629) were included. Physical activity, measured via self-report 6 times over 8 years, was converted to MET hr/wk for analysis. Latent growth curve mixture models and latent profile models were used to analyze longitudinal PA trajectories and cross-sectional PA composition, respectively.
  
  
  RESULTS
  Three distinct, stable PA trajectories (highly, moderately, and minimally active) were identified with nearly 75% of the women classified as minimally active (≤ 8 MET-hr/wk). The majority of women who were at least moderately active engaged in a balanced combination of walking, moderate, and vigorous PA. Sociodemographic characteristics such as income, education, and past vigorous PA were predictive of PA trajectory, as were some health status indicators (eg, body mass index), but not health related quality of life.
  
  
  CONCLUSIONS
  Self-reported PA is largely stable across nearly a decade of follow-up in postmenopausal women.
authors.affiliation: Dept of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA, USA.
authors.forename: Huong Q
authors.initials: HQ
authors.lastname: Nguyen
authors.forename: Jerald R
authors.initials: JR
authors.lastname: Herting
authors.forename: Ruth
authors.initials: R
authors.lastname: Kohen
authors.forename: Cynthia K
authors.initials: CK
authors.lastname: Perry
authors.forename: Andrea
authors.initials: A
authors.lastname: LaCroix
authors.forename: Lucile Lauren
authors.initials: LL
authors.lastname: Adams-Campbell
authors.forename: Shirley A A
authors.initials: SA
authors.lastname: Beresford
authors.forename: Charles B
authors.initials: CB
authors.lastname: Eaton
authors.forename: Lesley
authors.initials: L
authors.lastname: Tinker
mesh_terms: D000368:Aged; D015444:Exercise; D005260:Female; D005500:Follow-Up Studies; D015438:Health Behavior; D006304:Health Status; D006801:Humans; D008019:Life Style; D008603:Mental Health; D008875:Middle Aged; D017698:Postmenopause; D011998:Recreation; D012959:Socioeconomic Factors; D013997:Time Factors