title: Exercise adherence, cardiopulmonary fitness and anthropometric changes improve exercise self-efficacy and health-related quality of life.
abstract: BACKGROUND
  Regular exercise increases exercise self-efficacy and health-related quality of life (HRQOL); however, the mechanisms are unknown. We examined the associations of exercise adherence and physiological improvements with changes in exercise self-efficacy and HRQOL.
  
  
  METHODS
  Middle-aged adults (N = 202) were randomized to 12 months aerobic exercise (360 minutes/week) or control. Weight, waist circumference, percent body fat, cardiopulmonary fitness, HRQOL (SF-36), and exercise self-efficacy were assessed at baseline and 12 months. Adherence was measured in minutes/day from activity logs.
  
  
  RESULTS
  Exercise adherence was associated with reduced bodily pain, improved general health and vitality, and reduced role-emotional scores (P(trend) ≤ 0.05). Increased fitness was associated with improved physical functioning, bodily pain and general health scores (P(trend) ≤ 0.04). Reduced weight and percent body fat were associated with improved physical functioning, general health, and bodily pain scores (P(trend) < 0.05). Decreased waist circumference was associated with improved bodily pain and general health but with reduced role-emotional scores (P(trend) ≤ 0.05). High exercise adherence, increased cardiopulmonary fitness and reduced weight, waist circumference and percent body fat were associated with increased exercise self-efficacy (P(trend) < 0.02).
  
  
  CONCLUSIONS
  Monitoring adherence and tailoring exercise programs to induce changes in cardiopulmonary fitness and body composition may lead to greater improvements in HRQOL and self-efficacy that could promote exercise maintenance.
authors.affiliation: Dept of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
authors.forename: Ikuyo
authors.initials: I
authors.lastname: Imayama
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Alfano
authors.forename: Caitlin E
authors.initials: CE
authors.lastname: Mason
authors.forename: Chiachi
authors.initials: C
authors.lastname: Wang
authors.forename: Liren
authors.initials: L
authors.lastname: Xiao
authors.forename: Catherine
authors.initials: C
authors.lastname: Duggan
authors.forename: Kristin L
authors.initials: KL
authors.lastname: Campbell
authors.forename: Karen E
authors.initials: KE
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: D000368:Aged; D001837:Body Weights and Measures; D015444:Exercise / Q000502:physiology* / Q000523:psychology*; D005260:Female; D015438:Health Behavior; D006304:Health Status; D006801:Humans; D008297:Male; D008603:Mental Health; D008875:Middle Aged; D010146:Pain / Q000453:epidemiology; D010349:Patient Compliance; D010809:Physical Fitness / Q000502:physiology* / Q000523:psychology*; D011788:Quality of Life; D020377:Self Efficacy