High-Intensity Interval Training Benefits Chronic Stroke Patients

To optimize walking exercise capacity in chronic stroke patients, a recent study suggests that training at vigorous walking intensity is more effective than moderate intensity. The findings appeared in JAMA Neurology.

“For walking rehabilitation after stroke, training intensity and duration are critical dosing parameters that lack optimization,” the researchers wrote. To conduct this study, the investigators assessed 55 participants, of which 27 were randomized to receive high-intensity interval training (HIIT) and 28 received moderate-intensity aerobic training (MAT). Each program included 45 minutes of walking practice 3 times per week over the duration of 12 weeks. However, there was a marked difference in intensity, with the HIIT regimen using repeated 30-second bursts of walking at a safe speed while targeting an average aerobic intensity above 60% of the heart rate reserve (HRR), while the MAT protocol used continuous walking at moderate speed to maintain an initial target of 40% of HRR, progressing to 60% as tolerated. The main outcome of interest was defined as 6-minute walk test distance.

According to the results, both groups had had similar 6-minute walk test distance changes after 4 weeks (HIIT= 27 m [95% CI, 6-48 m]; MAT, 12 m [95% CI, −9 to 33 m]; mean difference, 15 m [95% CI, −13 to 42 m]; P = .28), but participants in the HIIT program exhibited superior walking gains after 8 weeks (58 m [95% CI, 39-76 m] vs 29 m [95% CI, 9-48 m]. Moreover, the HIIT group group displayed superior improvements in secondary outcomes that were assessed, such as gait speed and fatigue.

“These findings show proof of concept that vigorous training intensity is a critical dosing parameter for walking rehabilitation,” the researchers concluded. “In patients with chronic stroke, vigorous walking exercise produced significant and meaningful gains in walking capacity with only 4 weeks of training, but at least 12 weeks were needed to maximize immediate gains.”