Objective: To compare the effects of a group-mediated cognitive behavioral exercise intervention (GMCB) with traditional center-based exercise therapy (TRAD) on objectively assessed levels of physical activity (PA) and mobility in sedentary patients with knee osteoarthritis (OA).
Methods: The Improving Maintenance of Physical Activity in Knee Osteoarthritis Trial-Pilot (IMPACT-P) was a 12-month, 2-arm, single-blind, randomized controlled pilot study designed to compare the effects of GMCB and TRAD on 80 sedentary patients with knee OA with self-reported difficulty in daily activities [mean age 63.5 yrs, 84% women, mean body mass index (BMI) 32.7 kg/m(2)]. Objective assessments of PA (LIFECORDER Plus Accelerometer) and mobility (400-m walk) were obtained at baseline, 3 months, and 12 months by study personnel blinded to participants' treatment assignment.
Results: Intent to treat 2 (treatment: GMCB and TRAD) × 2 (time: 3 mos and 12 mos) analyses of covariance of controlling for baseline, age, sex, and BMI-adjusted change in the outcomes demonstrated that the GMCB intervention yielded significantly greater increases in PA (p < 0.01) and a nonsignificant yet more favorable improvement in mobility (p = 0.09) relative to TRAD. Partial correlation analyses also revealed that change in PA was significantly correlated with the 400-m walk performance at 3-month (r = -0.51, p < 0.01) and 12-month (r = -0.40, p < 0.01) followup assessments.
Conclusion: Findings from the IMPACT-P trial suggest that the GMCB treatment resulted in significantly greater improvement in PA and nonsignificant yet more favorable change in mobility relative to TRAD.
Keywords: AGING; EXERCISE; MOBILITY; OSTEOARTHRITIS; PHYSICAL ACTIVITY.