Alternating Hot-Cold Water Immersion Facilitates Motor Function Recovery in the Paretic Upper Limb After Stroke: A Pilot Randomized Controlled Trial

Objective: To assess the effectiveness of alternating hot-cold water immersion (AHCWI) in patients with acute stroke. Design: A single-blind pilot randomized controlled trial. Setting: Department of Rehabilitation Medicine of a medical center. Participants: Early stroke survivors (N=24) with moderate-to-severe arm paresis. Interventions: In addition to conventional rehabilitation, eligible patients were randomly assigned to an AHCWI group (n=12, for AHCWI) or a control group (n=12, for upper limb [UL] cycling exercises) 5 times per week for 6 weeks. Main Outcome Measures: The Fugl-Meyer Assessment motor-UL (FMA-UL) score, Motricity Index-UL (MI-UL) score, modified Motor Assessment Scale (MMAS; including its UL sections, MMAS-UL) score, Berg Balance Scale score, Barthel Index (BI), and modified Ashworth Scale score were assessed by the same uninvolved physical therapist at baseline and after 4 and 6 weeks of intervention. Results: Compared with the control group, the AHCWI group performed better, with significant group effects (P<.05), and exhibited significant improvements in FMA-UL, MI-UL, and MMAS-UL scores at 4 and 6 weeks (P<.05). Although the remaining outcomes were not significantly different, they favored the AHCWI group. Notably, a significant difference was observed in the BI at 4 weeks (P=.032). Significant changes in the muscle tone or adverse effects were not observed in either group after the intervention. Conclusions: AHCWI with stroke rehabilitation is feasible and may facilitate motor function recovery of the paretic UL after a stroke.