title: Physical activity predicts changes in body image during obesity treatment in women.
abstract: OBJECTIVE
  This study examined effects of a behavioral weight management intervention on body image (evaluative and investment dimensions) and explored the potential mediating role of structured and lifestyle physical activity (PA).
  
  
  METHODS
  The study was a longitudinal randomized controlled trial, including a 1-yr behavior change intervention and a 2-yr follow-up (225 women, 37.6 ± 7 yr, body mass index = 31.5 ± 4.1 kg·m). Statistical analyses comprised mixed-design ANOVAs with repeated measures, bivariate/partial correlations, and mediation analyses.
  
  
  RESULTS
  Body image improved considerably in both groups, favoring the intervention group (small to moderate effect sizes: 0.03-0.05), but began to deteriorate from 12 to 24 months, especially in the intervention group. Consequently, at 24 months, between-group differences were small and did not reach significance. Yet, levels of body dissatisfaction and dysfunctional investment remained below initial values (for both groups). Results were similar for both body image dimensions. Structured PA (at 12 and 24 months) and lifestyle PA (at 24 months) were positively associated with (r > -0.25, P < 0.05) and partially mediated body image improvements, especially in the investment component (95% confidence interval of -1.88 to -0.27 for structured PA at 12 months, 95% confidence interval of -1.94 to -0.21 for lifestyle PA at 24 months). In general, change in evaluative body image was not mediated by exercise participation, seeming more dependent on weight change.
  
  
  CONCLUSIONS
  These findings highlight the importance of PA as a contributing factor in the improvement of body image in overweight/obese women, mainly by reducing excessive salience of appearance to one's life and self. Lifestyle PA may also be a valid option, particularly in the long term. Exercise might provide a buffer against body image deterioration overtime, favoring lasting weight loss maintenance.
authors.affiliation: Faculty of Human Kinetics, Technical University of Lisbon, Lisbon, Portugal.
authors.forename: Eliana V
authors.initials: EV
authors.lastname: Carraça
authors.forename: David
authors.initials: D
authors.lastname: Markland
authors.forename: Marlene N
authors.initials: MN
authors.lastname: Silva
authors.forename: Sílvia R
authors.initials: SR
authors.lastname: Coutinho
authors.forename: Paulo N
authors.initials: PN
authors.lastname: Vieira
authors.forename: Cláudia S
authors.initials: CS
authors.lastname: Minderico
authors.forename: Luís B
authors.initials: LB
authors.lastname: Sardinha
authors.forename: Pedro J
authors.initials: PJ
authors.lastname: Teixeira
mesh_terms: D000328:Adult; D001521:Behavior Therapy / Q000379:methods*; D001828:Body Image / Q000523:psychology*; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology*; D015444:Exercise; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008019:Life Style; D008137:Longitudinal Studies; D008875:Middle Aged; D009043:Motor Activity; D009765:Obesity / Q000523:psychology* / Q000628:therapy; D011795:Surveys and Questionnaires