The effects of dual-task training with different task priorities on physical performance and cognitive status in patients with Parkinson's disease: a single-blind, randomized controlled trial.

Two strategies have been identified for dual-task training (DTT). These strategies are "variable-priority" DTT (V-DTT) and"fixed-priority" DTT (F-DTT). However, no study compared this DTT methods in patients with Parkinson's disease (PwPD). This study was planned to investigate the effects of V-DTT and F-DTT on physical performance, cognitive status and daily life in PwPD. 30 PwPD randomly allocated to V-DTT, F-DTT or single-task training (STT) groups. All groups received 60-minute training, two-times per week for 6-weeks. Physical performance, cognitive skills and activities of daily living (ADL) were evaluated before and after the training. All groups showed significant improvements in motor symptoms (MS), clinical symptoms (CS), functional balance (FB), stability limits (SL), static and dynamic balance (SB, DB), walking speed (WS), complex and backward walking skills (CWS, BWS), functional mobility (FM), ADL, and kinesiophobia. However, only DTT groups showed improvements in executive functions (EF), attention, verbal fluency (VF) and dual-tasking ability (DTA). Moreover, only V-DTT showed improvements in processing speed (PS). When the three groups were compared, the order of improvements in MS, SL, DB, WS, CWS, FM, EF, attention, VF, and ADL were as follows: V-DTT=F-DTT>STT. The order of improvements in FB, SB, and DTA was as follows: V-DTT>F-DTT>STT. The order of improvements in BWS and kinesiophobia was as follows: V-DTT=F-DTT=STT. V-DTT is more beneficial in some motor functions, especially in static situations, and in some cognitive functions. V-DTT also positively affected the PwPDs' DTA in ADL.Clinical trial registry: NCT06794177, 21 January 2025, retrospectively registered.