Could high-intensity treadmill exercise slow the progression of symptoms among individuals with Parkinson disease (PD)? Authors of a new study say that while more research needs to be done, their randomized clinical trial has proven the intervention to be safe, with indications that sufficiently vigorous treadmill work 3 times a week slowed severity at 6 months.
Their findings, published in JAMA Neurology (abstract only available for free), are based on a study of 128 patients with stage 1 or 2 PD who were within 5 years of diagnosis. Authors wanted to find out whether endurance exercise—particularly the high-intensity variety—had any effect on PD severity over time. Authors say the study is the first to evaluate the effects of exercise at 80% to 85% of maximum heart rate among patients with PD, and 1 of only a handful that focused on disease severity as an outcome, rather than fitness or functional measures.
Researchers divided the participants into 3 groups: a high-intensity group that received a prescription for 30 minutes of target heart rate (80% to 85% of maximum heart rate) treadmill work 4 times a week, a moderate-intensity group that received a prescription for 30 minutes of treadmill work that reached 60% to 65% of maximum heart rate 4 times a week, and a usual-care group that was told to continue with their current rates of physical activity. Sessions during the first 2 weeks were conducted that the study site; after that participants engaged in the treadmill work at local gyms or health centers. Patients wore heart rate monitors for all sessions and participated in monthly calls with study coordinators.
At the end of 6 months, participants completed the Unified Parkinson Disease Rating Scale (UPDRS), and researchers compared those scores with UPDRS scores at baseline.
Authors of the study found that individuals in the usual-care group recorded an average 3.2 point increase in PD severity in the UPDRS motor score component after 6 months, while the high-intensity treadmill group averaged a 0.3 increase—a difference significant enough to warrant further investigation, they believe. But the same couldn't be said for the moderate-intensity group, which averaged a 2 point increase in UPDRS motor scores, representing no significant difference between that group and the usual care group.
Additionally, researchers found few adverse events associated with the high-intensity group, "demonstrating that patients with [PD] can exercise safely without direct supervision when guided by exercise specialists," they write.
"In light of a recent report that low-dose, patient-centered, goal-directed physiotherapy and occupational therapy in patients in the early stages of [PD] is not effective, a demonstration of the nonfutility of high-intensity treadmill exercise in patients with mild [PD] is particularly important," authors write.
Authors acknowledge limitations to their study, noting that only treadmill work was studied (as opposed to other forms of endurance training); that intensities were reached by manipulating both treadmill speed and incline (as opposed to isolating the effects of each); and that the study did not address other types of exercise that are also important in addressing PD, such as strength training.
The bottom line, however, remains, as far as the authors are concerned: not only is high-intensity treadmill exercise safe for patients with PD, it shows promise as an approach to lessen disease severity. More research should be done, they write, but "meanwhile, clinicians may safely prescribe exercise at this intensity level for this population."
Authors of the study include APTA members Margaret Schenkman, PT, PhD, FAPTA; Anthony Delitto, PT, PhD, FAPTA; Deborah Josbeno, PT, PhD; and Cory Christiansen, PT, PhD.
Research-related stories featured in PT in Motion News are intended to highlight a topic of interest only and do not constitute an endorsement by APTA.