High-Intensity Interval Training Enhances Cardiovascular and Functional Outcomes Compared With Moderate-Intensity Continuous Training in Higher-Functioning Chronic Stroke

Abstract

Objective: To compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on cardiovascular function, gait ability, and hematological variables in chronic stroke survivors.Methods: Twenty-nine higher-functioning, ambulatory chronic stroke survivors were randomized to HIIT (n=15) or MICT (n=14). Participants underwent supervised training three times weekly for six weeks, consisting of 30 minutes conventional therapy followed by 40 minutes aerobic exercise (HIIT: six 1-minute high-intensity intervals at 80%–100% maximum heart rate (HRmax) with 4-minute active recovery; MICT: continuous exercise at 60%–80% HRmax). Outcomes included cardiovascular function (maximal oxygen uptake [VO2max], HRmax, walking heart rate), gait (10-Meter Walk Test, Timed Up and Go test, 6-Minute Walk Test), and lipid profiles (low-density lipoprotein, high-density lipoprotein, triglycerides).Results: In this higher-functioning cohort (n=29), HIIT showed significantly greater improvements than MICT in VO2max (F=40.574, p=0.001), HR_max (F=24.661, p=0.001), walking heart rate (F=11.277, p=0.002), 10-Meter Walk Test (F=20.865, p=0.001), Timed Up and Go test (F=12.317, p=0.002), and 6-Minute Walk Test (F=9.742, p=0.004). Lipid profiles improved significantly within the HIIT group only (p<0.05), no between-group differences were observed.Conclusion: In higher-functioning chronic stroke survivors, HIIT was superior to MICT for cardiovascular fitness and functional mobility under a matched exposure; lipid changes occurred within HIIT only without between-group effects. These findings support incorporating HIIT into stroke rehabilitation programs to enhance recovery outcomes.