Effects of Adding Treadmill Training to Conventional Physiotherapy on Lower-Limb Thermal Asymmetry, Motor Function, and Walking Capacity in Patients with Chronic Stroke: A Randomized Controlled Trial

Background/objectives: Thermal asymmetries between the affected and unaffected sides of the body are common after stroke and can be detected using infrared thermography; however, their responsiveness to rehabilitation and its relationship with motor and functional performance remain unclear. This study investigated whether the addition of treadmill training to conventional physiotherapy modifies lower-limb thermal asymmetry and explored its relationship with functional outcomes in individuals with chronic stroke. Methods: A randomized controlled trial was conducted in 22 individuals with chronic stroke randomly assigned to either an intervention group [n = 12] or a control group [n = 10]. All participants received conventional physiotherapy twice weekly for 12 weeks, while the intervention group additionally performed treadmill training. Thermal asymmetry was assessed using infrared thermography, whereas motor function and walking capacity were evaluated using the Fugl–Meyer Assessment for the Lower Extremity and the Six-Minute Walk Test. Results: Both groups showed reduced thermal asymmetry after the intervention, with no significant between-group differences. Significant improvements in motor function (p = 0.016) and walking distance (p = 0.016) were observed only in the intervention group. Between-group analysis revealed greater motor improvement in the intervention group (p = 0.017). Baseline-adjusted analyses confirmed superior motor function and walking capacity outcomes in the intervention group. Conclusions: Infrared thermography detected changes in lower-limb thermal asymmetry following the 12-week physiotherapy program in individuals with chronic stroke, with no significant between-group differences. In contrast, treadmill training produced superior improvements in motor function and walking capacity. These differing patterns suggest that thermographic and functional assessments may provide complementary information regarding recovery after chronic stroke.