Different training strategies to improve turning performance, functional mobility and brain activity in individuals with Parkinson’s disease

Participants in each group received one-on-one 30 minutes of specific exercise, turning-based treadmill training, or control exercise, respectively, followed by a 10-minute turning/walking training on a level surface for a total of 12 sessions over a 4–6-week period by a physiotherapist. All subjects needed to register of attendance at each session to monitor adherence. Specific exercise: Our previous study found that balance ability and lower extremity muscle strength correlated significantly with turning performance in individuals with PD. Therefore, participants in the specific exercise group received specific exercise training that included 20 minutes of balance exercises and 10 minutes of muscle strengthening exercises. The balance exercises focused on both static and dynamic standing balance training. For instance, standing on the ground composed of different materials and bases of support, and single leg stance were treatment programs for static balance training. For dynamic balance training, catching/throwing a ball, the ring toss game, and forward reaching to different directions were included. The strengthening training focused on hip extensors, abductors, and knee extensors, which were highly correlated with turning performance. Training intensity began from 50% of maximal voluntary contraction (MVC) for 10 repetitions, and the intensity increased to 75%–80% of MVC progressively. After the individual muscle strengthening exercises, participants performed squatting, stepping up/down in the standing position, and bridging and hip circle activities in the supine position. Normal breathing was emphasized during the training session. Turning-based training: Participants in the turning-based training group received the 30 minutes turning training on a rotational treadmill. This rotational treadmill (Rmax Science & Technology Co., Ltd., New Taipei City, Taiwan) was designed to provide turning-based (task-specific) training. The basic design principle of this rotational treadmill is similar to the regular treadmill except for its circular, running motor belt. The small radius (0.8 m) forces participants to perform a turning action rather than walking straight. Following the above-described, 30-minute exercise training for each group, a 10-minute over-the-ground turning program was carried out. This program included S-shaped, 8-shaped, square-shaped, and oval-shaped turning walking with verbal cues for gait correction.