# The combined effect of task-oriented treadmill and high-intensity interval training on balance, gait parameters, and ADL in patients with chronic stroke: A randomized controlled trial with short-term follow-up PMID: 42011378 Journal: Journal of exercise science and fitness Published: 2026-07-01 Authors: Kim K, Jung NJ, Kang MB ## Question Does task-oriented treadmill training combined with HIIT improve balance, spatiotemporal gait parameters, and activities of daily living more than HIIT treadmill training alone in patients with chronic stroke? ## Summary In a 4-week assessor-blinded randomized trial of 30 inpatient adults with chronic stroke, task-oriented treadmill HIIT using obstacle crossing was compared with high-intensity interval treadmill training alone. Both groups trained 30 minutes per session, 3 times per week, and both improved over time. The task-oriented HIIT group showed greater improvements for several gait and balance measures and showed a stronger 2-week transfer effect, although between-group differences were not significant for cadence and modified Barthel Index at post-test. ## Population - Chronic stroke patients in an inpatient rehabilitation ward, able to walk at least 10 m, gait speed less than 0.8 m/s, and MMSE at least 24. - Sample size: 30 - Age: TO-HIIT 59.53 +/- 8.96 years; HIIT 53.27 +/- 10.13 years. - Sex: TO-HIIT 7 male/8 female; HIIT 11 male/4 female. - Fitness level: Ambulatory chronic stroke patients with FAC about 3.3-3.6 and gait speed below 0.8 m/s. - Health status: Stroke onset 6-24 months prior; severe visual/cognitive impairment, cardiovascular/circulatory disease, and lower-extremity medical instability excluded. ## Methodology - Parallel-group assessor-blinded randomized controlled trial with 1:1 allocation and 2-week follow-up. - 4 weeks of training plus 2-week follow-up. - Inpatient rehabilitation ward of K Hospital in Daegu, Republic of Korea. - Randomized and controlled study design. ## Protocol - TO-HIIT. - Modality: Treadmill walking with obstacle-crossing tasks and body-weight support harness. - Work intervals: 2 minutes at 70%-80% HRR. - Recovery: 2 minutes active recovery at 30%-40% HRR. - Sets or repetitions: Repeated cycles during a 20-minute main set, consistent with five work bouts and five recovery bouts. - Intensity: Target HRR calculated by Karvonen formula with real-time HR-guided treadmill speed titration. - Session duration: 30 minutes including 5-minute warm-up, 20-minute main set, and 5-minute cool-down. - Frequency: 3 sessions/week. - Program length: 4 weeks. - Progression: Obstacle task progressed weekly by affected/non-affected stepping direction, obstacle size, and randomization. - HIIT. - Modality: Treadmill walking with body-weight support harness, no task-oriented obstacle component. - Work intervals: 2 minutes at 70%-80% HRR. - Recovery: 2 minutes active recovery at 30%-40% HRR. - Sets or repetitions: Repeated cycles during a 20-minute main set, consistent with five work bouts and five recovery bouts. - Intensity: Target HRR calculated by Karvonen formula with real-time HR-guided treadmill speed titration. - Session duration: 30 minutes including 5-minute warm-up, 20-minute main set, and 5-minute cool-down. - Frequency: 3 sessions/week. - Program length: 4 weeks. - Progression: Treadmill speed adjusted in real time to maintain HRR targets; no task-oriented progression. ## Outcomes ### Gait parameters Status: improved Significant time x group interactions occurred for step length, stride length, cadence, double limb support, and single support; TO-HIIT showed greater post-test and follow-up advantages for most gait variables. Time x group p<.05 for all gait parameters; partial eta2 examples: step length .601, stride length .797, cadence .536, double limb .589, single support .645. ### Static balance Status: improved TO-HIIT improved COP 95% area, COP path length, and COP average velocity more than HIIT alone. Time x group partial eta2: COP 95% area .804, COP path length .613, COP average velocity .153; p<.05. ### Modified Barthel Index Status: mixed MBI improved over time and showed a significant time x group interaction, but post-test between-group difference was not significant after correction; follow-up favored TO-HIIT. Time x group partial eta2=.510, p<.05; post-test between-group p=.027 not significant under p<.025 correction; follow-up p=.016 significant. ### Completion and dropout Status: mixed Thirty participants completed the study after 6 withdrawals from 36 selected/randomized participants. TO-HIIT n=15 and HIIT n=15 completed; 3 withdrawals per group. ## Practical Insights - For rehabilitation transfer, pairing HIIT with task-specific gait challenges may be more useful than intensity-focused treadmill intervals alone. - A 30-minute session using 5-minute warm-up, 20-minute 2:2 intervals, and 5-minute cool-down is a reproducible clinical structure. - Obstacle/task progression can be treated as a programming variable separate from intensity. - Translation to consumer HIIT is limited because the intervention required harnessed treadmill walking, therapist supervision, and clinical screening. ## Limitations - Small sample size. - Sample size assumptions may have been optimistic. - Homogeneous selected sample with walking speed <0.8 m/s, FAC >=3, and MMSE-K >=24. - Short 4-week intervention. - Only 2-week follow-up. - No long-term sustainability data. - Participants and therapists could not be blinded. - Achieved HRR, RPE, attendance percentage, and adverse event counts were not reported. ## Safety And Adherence - No adverse event count was reported in the extracted full text. - One TO-HIIT participant withdrew because of other medical problems. - Protocol required immediate stopping for shortness of breath, chest pain, muscle discomfort, or other distress. - Vital signs were to be monitored after distress, and training withheld until attending physician clearance. ## Original Sources - [PubMed](https://pubmed.ncbi.nlm.nih.gov/42011378/) (pubmed) - [DOI](https://doi.org/10.1016/j.jesf.2026.200475) (doi) - [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13091996/) (full text) ## Agent Guidance Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.