A four-week walking exercise programme in patients with knee osteoarthritis improves the ability of dual-task performance: a randomized controlled trial.

Objective: To investigate whether a four-week walking exercise programme in patients with knee osteoarthritis improves the ability of dual-task performance in older adults with knee osteoarthritis.

Design: A randomized controlled trial with two groups: a walking group and a control group.

Subjects: Forty older adults with knee osteoarthritis, 20 participants in each group.

Intervention: The walking intervention was designed to increase the number of steps walked daily. The walking group was instructed to increase their number of steps to 3000 steps more than before the intervention.

Main Outcome Measures: Dual-task performance was computed by an automaticity index: the walking velocity under single-task condition/under dual-task conditions × 100 (%), defined as automaticity. The nearer to 100% automaticity, the better the dual-task performance. Decrease of the Trail Making Test (TMT) performance was defined as ΔTMT. ΔTMT was calculated as the difference between times (part B-part A) as a measure of executive function. In addition, functional ability was measured by the Japanese Knee Osteoarthritis Measure.

Results: The walking group improved significantly in automaticity (P < 0.001, from 75.2 (7.6) to 86.9 (10.4), ΔTMT (P < 0.001, from 63.4 (43.1) to 48.3 (29.6)) and Japanese Knee Osteoarthritis Measure score (P < 0.001, from 54.4 to 51.9) compared with before the intervention, while the control group displayed no significant differences.

Conclusions: We found that walking exercise improves executive function and dual-task performance.