NASHVILLE—When paired with repetitive task practice, exercise on a motorized stationary bicycle results in greater improvements in motor function among patients with stroke, compared with exercise on a nonmotorized stationary bicycle and repetitive task practice alone, according to research presented at the 2015 International Stroke Conference. Exercise on a motorized stationary bicycle also may improve nonmotor function and aerobic capacity at six to 12 months after a stroke.
This method of assisted exercise “has [been] shown to help patients with Parkinson’s disease … and may improve neuroplasticity,” said Susan Linder, PT, DPT, NCS, a physical therapist at the Cleveland Clinic in Ohio. The therapy helps patients with limited mobility to pedal and to achieve and maintain the intensity of training considered necessary to affect brain function.
Susan Linder, PT, DPT, NCS
Exercise Versus Task Practice Alone
Based on the findings of previous research, Dr. Linder and colleagues hypothesized that intensive aerobic exercise training combined with repetitive task practice would prime the CNS to exploit the motor learning effects of task practice. To test their hypothesis, the investigators studied 17 people (ages 23 to 84) who had had a stroke six to 12 months previously. All patients underwent repetitive task practice to help them regain arm use. Activities included relearning how to hold a cup or fork or how to dress. The investigators then randomized the participants to one of three treatment arms in addition to this therapy.
One of the three groups underwent forced exercise on a motorized stationary bicycle, one group underwent voluntary exercise on a nonmotorized stationary bicycle, and the third group underwent time-matched repetitive task practice. Participants in the forced exercise and voluntary groups completed one 45-minute session of stationary bicycling followed immediately by one 45-minute session of upper extremity repetitive task practice. The rate of cycling for the forced exercise group was increased to approximately 35% faster than the participants’ voluntary pedaling rate. All participants completed a total of 24 exercise sessions during an eight-week period.
Forced Exercise Improved Depression
Patients in all three groups made improvements in motor function, as measured by the Fugl–Meyer Assessment. Only the improvements by the forced exercise group achieved significance, however. Participants who exercised on the motorized bicycle had an improvement of 12.3 points on the Fugl–Meyer Assessment, compared with a 4.8-point improvement among participants who used the nonmotorized bicycle and a 4.4-point improvement among participants who had approximately twice as much repetitive task practice but no aerobic exercise. The difference between the forced exercise group and the other groups was statistically significant.
“The component of our sample that did not allow us to reach definitive conclusions regarding these results was that the forced [exercise] group was significantly higher functioning at baseline, compared with the other two groups,” said Dr. Linder. “A larger sample, along with stratified randomization according to age and baseline Fugl–Meyer scores, would likely allow us to achieve significance, according to our power analysis.”
The forced exercise and voluntary exercise groups also had improvements in cardiovascular fitness, as measured by peak VO2, but only the voluntary group’s changes were statistically significant.
In addition, patients who underwent forced exercise had improvements in depression, as measured by the Centers for Epidemiological Studies Depression Scale (CES-D). This group, however, had significantly greater CES-D scores at baseline than the others. All participants had improvements in the physical subscale of the Stroke Impact Scale, but those improvements did not persist at four weeks’ follow-up.
“Not only are we improving motor recovery with half the amount of task practice, but we’re also improving cardiovascular health, and stroke patients often have cardiovascular comorbidities,” said Ms. Linder. “If we can improve motor recovery and cardiovascular health simultaneously, patients can regain lost motor function and improve their quality of life.”
The researchers plan to conduct another, similar study of the effects of aerobic exercise on motor recovery among patients with stroke. In the new study, the researchers will stratify randomization to adjust for potentially confounding baseline demographic variables such as age and baseline Fugl–Meyer scores, said Dr. Linder.
—Erik Greb