Research Highlights:
Embargoed until 4 a.m. CT/5 a.m. ET, Thursday, Aug. 8, 2024
DALLAS, Aug. 8, 2024 — One-minute, short bursts of high-intensity interval training for 19 minutes may be more effective for improving fitness among people six months or more after a stroke than traditional, 20-30 minutes of moderate-intensity exercise sessions, according to research published today in Stroke , the peer-reviewed scientific journal of the American Stroke Association, a division of the American Heart Association.
“This study shows that people with stroke can also benefit from high-intensity interval training,” said Kevin Moncion, Ph.D., a physiotherapist who led this study as part of his doctoral studies at McMaster University in Hamilton, Ontario, Canada. “With the right support and guidance, stroke survivors can safely and effectively engage in high-intensity interval training, significantly improving their overall health and recovery.”
The multi-site trial took place between September 2018 and March 2024 and included stroke survivors between six months to 5 years after a stroke. Researchers randomly grouped participants to receive either three days per week of 12 weeks of high-intensity interval training or three days per week of 12 weeks of traditional moderate exercise sessions. The high-intensity interval training protocol involved ten 1-minute intervals of high-intensity exercise, interspersed with nine 1-minute low-intensity intervals, for 19 minutes total. The moderate intensity continuous training involved 20 to 30 minutes of steady exercise at moderate intensity.
Researchers then compared fitness levels, cardiovascular risk factors such as blood pressure and stiffness of blood vessels, walking speeds and distances between the two groups. All assessments were repeated one final time 8 weeks after the exercise interventions to evaluate whether the changes were sustained over time.
Researchers found:
“This is the first randomized trial to examine a time-efficient, high intensity interval training program to incorporate a phased and progressive approach,” said senior author Ada Tang, Ph.D., a physiotherapist, professor and assistant dean of Rehabilitation Science at McMaster University. “We also used an adaptive recumbent stepper, which we believe allowed more people to participate in high-intensity interval training, even those who cannot walk fast enough or long enough on a treadmill.”
The limitations of the study include that study participants were higher functioning stroke survivors from a physical standpoint who were at lower risk for heart disease. Study minimum criteria included the ability to walk 10 meters without physical assistance of another person, although the use of cane or walker was permitted. Outcome assessments were unblinded at follow-up, which may have influenced results. Lastly, enrollment and exercise for the trial was halted two years for COVID-19 lockdowns, thus inflating the rate of participants who left the study and potentially limiting the statistical power of the analysis.
In 2021, there were 7.44 million deaths attributable to stroke worldwide, according to the American Heart Association’s Heart Disease and Stroke Statistics 2024 Update .
Future research should examine stroke survivors with more severe impairment in physical function or heart disease risk, according to the study authors.
“Stroke rehabilitation professionals now have evidence to support implementing short, high-intensity interval training protocols in clinical practice. We showed our program is safe and effective at improving fitness and walking distance in people after stroke, which are important outcomes for stroke survivors,” Tang said.
Study details and background:
Co-authors, disclosures and funding sources are listed in the manuscript.
Studies published in the American Heart Association’s scientific journals are peer-reviewed. The statements and conclusions in each manuscript are solely those of the study authors and do not necessarily reflect the Association’s policy or position. The Association makes no representation or guarantee as to their accuracy or reliability. The Association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific Association programs and events. The Association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and biotech companies, device manufacturers and health insurance providers and the Association’s overall financial information are available here .
Additional Resources:
###
About the American Stroke Association
The American Stroke Association is devoted to saving people from stroke — the No. 2 cause of death in the world and a leading cause of serious disability. We team with millions of volunteers to fund innovative research, fight for stronger public health policies and provide lifesaving tools and information to prevent and treat stroke. The Dallas-based association officially launched in 1998 as a division of the American Heart Association. To learn more or to get involved, call 1-888-4STROKE or visit stroke.org . Follow us on Facebook , X .
Stroke
Cardiorespiratory Fitness Benefits of High- Intensity Interval Training After Stroke: A Randomized Controlled Trial
8-Aug-2024