Changes in sedentary time and physical activity in response to an exercise training and/or lifestyle intervention.

Author(s): Kozey-Keadle S,  Staudenmayer J,  Libertine A,  Mavilia M,  Lyden K,  Braun B,  Freedson P

Journal: J Phys Act Health

Date: 2014 Sep

Major Program(s) or Research Group(s): CPFP

PubMed ID: 24184493

PMC ID: not available

Abstract: BACKGROUND: Individuals may compensate for exercise training by modifying nonexercise behavior (ie, increase sedentary time (ST) and decrease nonexercise physical activity [NEPA]). PURPOSE: 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.