title: Changes in sedentary time and physical activity in response to an exercise training and/or lifestyle intervention.
abstract: BACKGROUND
  Individuals may compensate for exercise training by modifying nonexercise behavior (ie, increase sedentary time (ST) and decrease nonexercise physical activity [NEPA]).
  
  
  OBJECTIVE
  To compare ST and NEPA during a 12-week exercise training and/or lifestyle intervention.
  
  
  METHODS
  Fifty-seven overweight/obese participants (19 M/39 F) completed the study (mean ± SD; age 43.6 ± 9.9 y, BMI 35.1 ± 4.6 kg/m2). There were no between-group differences in activity levels at baseline. Four-arm quasi-experimental intervention study 1) EX: exercise 5 days per week at a moderate intensity (40% to 65% VO2peak) 2) rST: reduce ST and increase NEPA, 3) EX-rST: combination of EX and rST and 4) CON: maintain habitual behavior.
  
  
  RESULTS
  For the EX group, ST did not decrease significantly (mean ((95% confidence interval) 0.48 (-2.2 to 3.1)% and there was no changes in NEPA at week-12 compared with baseline. The changes were variable, with approximately 50% of participants increasing ST and decreasing NEPA. The rST group decreased ST (-4.8 (0.8 to 7.9)% and increased NEPA. EX-rST significantly decreased ST (-5.1 (-2.2 to 7.9)% and increased time in NEPA at week-12 compared with baseline. The control group increased ST by 4.3 (0.8 to 7.9)%.
  
  
  CONCLUSIONS
  Changes in nonexercise ST and NEPA are variable among participants in an exercise-training program, with nearly half decreasing NEPA compared with baseline. Interventions targeting multiple behaviors (ST and NEPA) may effectively reduce compensation and increase daily activity.
authors.affiliation: Dept of Kinesiology, University of Massachusetts, Amherst, MA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Kozey-Keadle
authors.forename: John
authors.initials: J
authors.lastname: Staudenmayer
authors.forename: Amanda
authors.initials: A
authors.lastname: Libertine
authors.forename: Marianna
authors.initials: M
authors.lastname: Mavilia
authors.forename: Kate
authors.initials: K
authors.lastname: Lyden
authors.forename: Barry
authors.initials: B
authors.lastname: Braun
authors.forename: Patty
authors.initials: P
authors.lastname: Freedson
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology / Q000628:therapy; D050177:Overweight / Q000503:physiopathology / Q000628:therapy*; D057185:Sedentary Behavior