title: Effect of exercise on 24-month weight loss maintenance in overweight women.
abstract: BACKGROUND
  Debate remains regarding the amount of physical activity that will facilitate weight loss maintenance.
  
  
  METHODS
  Between December 1, 1999, and January 31, 2003, 201 overweight and obese women (body mass index [calculated as weight in kilograms divided by height in meters squared], 27 to 40; age range, 21-45 years) with no contraindications to weight loss or physical activity were recruited from a hospital-based weight loss research center. Participants were assigned to 1 of 4 behavioral weight loss intervention groups. They were randomly assigned to groups based on physical activity energy expenditure (1000 vs 2000 kcal/wk) and intensity (moderate vs vigorous). Participants also were told to reduce intake to 1200 to 1500 kcal/d. A combination of in-person conversations and telephone calls were conducted during the 24-month study period.
  
  
  RESULTS
  Weight loss did not differ among the randomized groups at 6 months' (8%-10% of initial body weight) or 24 months' (5% of initial body weight) follow-up. Post-hoc analysis showed that individuals sustaining a loss of 10% or more of initial body weight at 24 months reported performing more physical activity (1835 kcal/wk or 275 min/wk) compared with those sustaining a weight loss of less than 10% of initial body weight (P < .001).
  
  
  CONCLUSIONS
  The addition of 275 mins/wk of physical activity, in combination with a reduction in energy intake, is important in allowing overweight women to sustain a weight loss of more than 10%. Interventions to facilitate this level of physical activity are needed.
authors.affiliation: Physical Activity and Weight Management Research Center, University of Pittsburgh, 140 Trees Hall, Pittsburgh, PA 15261, USA. jjakicic@pitt.edu
authors.forename: John M
authors.initials: JM
authors.lastname: Jakicic
authors.forename: Bess H
authors.initials: BH
authors.lastname: Marcus
authors.forename: Wei
authors.initials: W
authors.lastname: Lang
authors.forename: Carol
authors.initials: C
authors.lastname: Janney
mesh_terms: D000328:Adult; D002149:Energy Intake; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D050177:Overweight / Q000378:metabolism / Q000628:therapy*; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D013997:Time Factors; D016896:Treatment Outcome; D015431:Weight Loss