title: Keeping the weight off: physical activity, sitting time, and weight loss maintenance in bariatric surgery patients 2 to 16 years postsurgery.
abstract: BACKGROUND
  Bariatric surgery patients often exhibit low levels of physical activity (PA), despite the presumed importance of PA as an adjunct to surgery for successful weight loss. Little is known regarding the associations of PA and sedentary behaviors to weight loss outcomes in the long term following surgery. The objective of the study was to assess the associations of PA and sitting time with weight status, weight loss, and weight maintenance outcomes in bariatric patients 2-16 years postsurgery.
  
  
  METHODS
  A total of 303 Roux-en-Y Gastric Bypass patients (73% female; mean age 47 ± 10 years, mean 7 ± 4 years since surgery) completed a telephone questionnaire. Patients reported moderate-to-vigorous PA (MVPA: # sessions/week ≥30 min) and average daily sitting time (h/day). Associations with various weight outcomes were assessed.
  
  
  RESULTS
  Only 48% of patients reported ≥1 session/week MVPA, and mean reported sitting time was 7 ± 4 h/day. Neither MVPA nor sitting time was associated with weight loss outcomes at patients' lowest weight postsurgery. However, both MVPA and sitting time were independently positively and inversely, respectively, associated with total (kg) weight loss, % weight loss, and % excess weight loss at current weight, as well as weight loss maintained vs. regained, controlling for age, sex, surgery type, presurgery BMI, total initial weight loss, and time since surgery.
  
  
  CONCLUSIONS
  Results demonstrate associations between MVPA and high sitting time and weight loss outcomes among bariatric patients in the long term. The implications for long-term weight management and concomitant health outcomes highlight the need for appropriate follow-up and interventions in this unique high-risk patient population.
authors.affiliation: Department of Kinesiology and Physical Education, McGill University, 475 Pine Ave W, Montreal, QC, H2W 1S4, Canada, Katya.Herman@uregina.ca.
authors.forename: Katya M
authors.initials: KM
authors.lastname: Herman
authors.forename: Tamara E
authors.initials: TE
authors.lastname: Carver
authors.forename: Nicolas V
authors.initials: NV
authors.lastname: Christou
authors.forename: Ross E
authors.initials: RE
authors.lastname: Andersen
mesh_terms: D000328:Adult; D050110:Bariatric Surgery; D002170:Canada / Q000453:epidemiology; D015444:Exercise; D005260:Female; D005500:Follow-Up Studies; D015438:Health Behavior; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000453:epidemiology* / Q000517:prevention & control* / Q000601:surgery; D010349:Patient Compliance / Q000706:statistics & numerical data*; D057185:Sedentary Behavior; D057566:Self Report; D011795:Surveys and Questionnaires; D013997:Time Factors; D015430:Weight Gain; D015431:Weight Loss