Stroke survivors who completed group-based aerobic exercise programs similar in design and duration to cardiac rehabilitation programs significantly improved their aerobic endurance and walking ability, according to new research in Journal of the American Heart Association.
Most current rehabilitation care following stroke has little to no focus on aerobic fitness, and when continued rehabilitation activity is suggested patients often fail to keep active without any support or guidance, according to an analysis of 19 published studies to assess the impact of aerobic exercise programs on endurance and walking ability after stroke.
“The physical therapy we currently provide to patients after a stroke focuses more on improving the ability to move and move well rather than on increasing how far and long you can move,” said Elizabeth Regan, DPT, study lead author, and Ph.D. candidate in Exercise Science at the University of South Carolina.
“It doesn’t matter how well you can walk if your endurance level keeps you at home.”
Nearly 500 adults average ages between 54-71 completed aerobic exercise programs similar in structure to cardiac rehabilitation.
Participants attended two to three sessions per week for about three months.
Of nearly two dozen different exercise groups, walking was the most common type of activity, followed by stationary cycling and then mixed mode aerobic exercise.
Physical abilities were tested before and after the intervention.
Looking at results by activity type, researchers found:
- Mixed aerobic activity provides the best result (4 treatment groups) followed by walking (12 treatment groups).
- Cycling or recumbent stepping (machine that allows stepping while in seated position) while still significant was the least effective (7 treatment groups).
- Overall, participants significantly improved their endurance level and walking speed.
- On average, participants walked almost half the size of a football field farther during a six-minute walking test. Participants with mild movement impairments benefited the most.
“These benefits were realized regardless of how long it had been since their stroke,” Regan said.
“Our analysis included stroke survivors across a wide range, from less than six months to greater than a year since their stroke, and the benefits were seen whether they started an aerobic exercise program one month or one year after having a stroke.”
“Cardiac rehab programs may be a viable option for patients after a stroke who have health risks and endurance losses similar to traditional cardiac rehab participants,” said Stacy Fritz, Ph.D., PT, the study’s co-author and associate professor of exercise science in the Physical Therapy Program at the University of South Carolina.
“Almost every hospital has a cardiac rehab program, so it’s an existing platform that could be used for stroke survivors. Funneling patients with stroke into these existing programs may be an easy, cost-effective solution with long-term benefits.”
While this study suggests group-based aerobic exercise programs improve health and endurance in stroke survivors, no control group analysis was performed for results comparison. Limited follow-up data were available to determine whether the health benefits persisted.
Stroke and ischemic heart disease accounted for 15 million out of 57 million deaths in 2016; these cardiovascular diseases have been the leading causes of death for the last 15 years .
Stroke incidence is proportionally related to age – the average population is aging – so stroke prevention and treatment is increasingly important.
Classic neurorehabilitation programmes for stroke survivors provide a ‘limited opportunity for cardiovascular exercise’ and ‘the use of moderate-intensity continuous exercise (MICE) to improve cardiorespiratory fitness.
Niether of these two types or exercise is routinely implemented in clinical practice. When used, their intensity may be insufficient to elicit a training effect .
Post stroke guidelines recommend MICE to improve aerobic capacity, mobility and walking speed.
However, effects on functional recovery, aerobic fitness and quality of life remain unclear .
Most stroke rehabilitation programs – which generally last only a few months – lack aerobic exercise training .
This might be due to lack of knowledge regarding exercise testing and prescription for people after stroke.
Classic stroke rehabilitation certainly does not include aerobic- or resistance-type high-intensity interval training (HIIT).
One assumption is that high-exertion activity would increase spasticity .
HIIT is a training that consists of repeated (very) short bursts of high-intensity exercises (at 85%-95% of peak heart rate) followed by low-intensity recovery activity.
HIIT improves fitness, ie, aerobic capacity in healthy as well as persons with cardiovascular diseases . Does HIIT constitute a safe and effective method to improve the lives of stroke survivors? What does science tell us?
What type of (research) knowledge exists regarding HIIT in stroke survivors?
HIIT for stroke survivors undoubtedly found its way into neurorehabilitation after many benefits were shown over the years ‘High-intensity interval training (HIIT) emerged as a powerful time-efficient alternative to MICE for individuals without known disability, as well as clinical populations’ .
Furthermore, HIIT might be superior to MICE in persons with heart disease .
To improve function, mobility and prevent further disease in stroke survivors there is emerging information from randomized controlled trials (RCTs) that HIIT may be safe and effective.
Billinger and colleagues write that “compared to lower intensity, higher intensity training elicits greater improvement in aerobic fitness among healthy adults, persons with heart disease, and persons with stroke”.
While we acknowledge that repetitive taks training (RTT) does not mimic high intensity training, we alert the read to the Cochrane Review which found low- to moderate-quality evidence for the effectiveness of repetitive task training (RTT) on upper and lower limb function in patients after stroke . Additionally,Veerbeek et al conclude that RTT intervention should be executed in high-intensity .
What are possible benefits of HIIT for stroke survivors?
One study found similar increases in VO2max in four weeks of HIIT compared to 6 months of moderate intensity continuous exercise (MICE) as well as improvements in (persistent hemiparetic) gait, walking economy, walking speed and walking distance in chronic stroke survivors .
Another trial compared HIIT with conventional care physiotherapy following moderate stroke demonstrating that HIIT leads to better results in cardiovascular fitness, reflected in improved self-rated functional mobility, i.e. improved independence in performing basic activities of daily living, improved maximum gait speed, balance and quality of life .
What is the level of effectiveness and safety in HIIT in stroke survivors? Is it accepted among stroke survivors?
Some reports suggest that HIIT is feasible and safe in moderate stroke patients .
Billinger and colleagues note that “low-intensity exercise can be prescribed for most, if not all, persons with stroke, higher intensities should be prescribed whenever safe and well tolerated because they are generally more effective“.
In addition to this, results from a safety analysis show the potential for HIIT in stroke survivors as an adjunct to established (pharmacological) therapy .
A feasibility study demonstrated its clinical applicability when necessary precautions for high-risk populations were taken into account with the American College of Sports Medicine guidelines .
Also, Boyne and colleagues report that HIIT appears to be safe with no serious adverse events being reported.
HIIT generally has good acceptance in chronic stroke patients .
Could HIIT be a big `HIT` for stroke rehabilitation?
Research in HIIT in stroke survivors is limited to feasibility studies and safety analyses (indicating the effectiveness of HIIT in stroke patients).
Some small clinical trials exist, primarily small sample-sized efficacy studies, which limit the generalizability of effects.
There is a need for high quality randomized controlled studies to address the questions in this blog.
HIIT for stroke survivors is safe and effective and is well accepted by many patients.
HIIT can rapidly show benefits such as improved quality of life in stroke patients.
Future research is needed to prove if HIIT has the chance to become the next big `HIT` in neurorehabilitation for stroke survivors.
More information:Journal of the American Heart Association (2019). DOI: 10.1161/JAHA.119.012761
Journal information: Journal of the American Heart Association
Provided by American Heart Association