title: Predicting adherence of adults to a 12-month exercise intervention.
abstract: BACKGROUND
  The purpose of this study was to (a) examine demographic, psychosocial, and physiological predictors of exercise adherence in a yearlong exercise intervention and (b) describe the trajectory of adherence over time.
  
  
  METHODS
  Participants were 51 men and 49 women aged 40 to 75 years. The supervised and home-based intervention consisted of 60 minutes/day, 6 days/ week of moderate-to-vigorous intensity exercise. Three adherence measures were used: (1) minutes/week, (2) MET-hours/week, and (3) change in cardiopulmonary fitness (VO2max). Predictors of adherence were determined separately by sex using mixed models and multivariable regression.
  
  
  RESULTS
  Participants performed 287 ± 98 minutes/week of moderate-to-vigorous activity with 71% adhering to at least 80% (288 minutes/week) of the prescription. Men adhered better than women (P < .001). Among women, adiposity-related variables were significantly related to poorer adherence on all 3 measures (P < .05). A less consistent pattern was observed among men but in follow-up analyses, adiposity was associated with fewer MET-hours/week of exercise. Social support, pain, and perceived benefits were predictive in some models. Men and nonobese women experienced peak adherence at 4 to 6 months, while obese women peaked during months 0 to 3.
  
  
  CONCLUSIONS
  When provided with supervision and support, previously sedentary men and women can achieve and maintain high levels of aerobic activity.
authors.affiliation: Dept of Kinesiology, University of Wisconsin-Madison.
authors.forename: Lisa
authors.initials: L
authors.lastname: Cadmus-Bertram
authors.forename: Melinda
authors.initials: M
authors.lastname: Irwin
authors.forename: Catherine
authors.initials: C
authors.lastname: Alfano
authors.forename: Kristin
authors.initials: K
authors.lastname: Campbell
authors.forename: Catherine
authors.initials: C
authors.lastname: Duggan
authors.forename: Karen
authors.initials: K
authors.lastname: Foster-Schubert
authors.forename: Ching-Yun
authors.initials: CY
authors.lastname: Wang
authors.forename: Anne
authors.initials: A
authors.lastname: McTiernan
mesh_terms: D050154:Adiposity / Q000502:physiology; D000328:Adult; D000368:Aged; D015444:Exercise; D005260:Female; D006296:Health Services; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D009765:Obesity / Q000523:psychology* / Q000628:therapy*; D010349:Patient Compliance