High-intensity treadmill exercise can be safely prescribed for patients with de novo Parkinson’s disease (PD) and may slow progression of some of the disease’s effects, according to a phase 2 clinical trial, the results of which were published in JAMA Neurology.
Preclinical studies, including one published in Experimental Neurology in 2003, that examined the link between exercise and PD in animals influenced development of the more recent research, the Study in Parkinson Disease of Exercise (SPARX).
“We began thinking about whether it was possible to [examine these effects in humans],” says lead author Margaret Schenkman, PhD, PT, FAPTA, Director of the Physical Therapy Program and Associate Dean for Physical Therapy Education at the University of Colorado School of Medicine. “It became clear that we needed to know the right dose [of exercise] before we started that type of study.”
Schenkman and other researchers from multiple institutions crafted the SPARX trial to determine a nonfutile dose of exercise that could be further researched in a phase 3 trial. They chose treadmills to effectively control the amount and intensity of exercise that the 128 SPARX trial participants performed.
Results and Implications
Of the participants, 43 engaged in high-intensity exercise at 80–85 percent of their maximum heart rate four days a week, 45 engaged in moderate-intensity exercise at 60–65 percent of maximum heart rate, and the remaining control group of 40 did not change their prior exercise habits, engaging in no more than three sessions of moderate exercise a week, if any.
Outcomes were determined by examining changes in participants’ Unified Parkinson’s Disease Rating Scale motor score after six months. This score tracks changes in tremors, agility, postural instability and other symptoms of PD, with a higher score signifying worsening symptoms.
The average increase in the score among the high-intensity group was three-tenths of a point, compared with two points in the moderate-intensity group and more than three points in the control group.
While both moderate- and high-intensity exercise were deemed safe, only the high-intensity group met the nonfutility threshold, paving the way for a phase 3 study to further determine the efficacy of high-intensity endurance exercise.
“Studies are also needed to elucidate the mechanism ...,” says co-lead author Daniel M. Corcos, PhD, Professor of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine at Northwestern University. “In the meantime, the best-informed advice we can give is to engage in high-intensity endurance exercise, weight training and balance training.”
Precautions are appropriate before PD patients begin exercise regimens.
“Someone who’s exercising at high intensity, especially if they have Parkinson’s, may have poor quality of movement,” says Laurie A. King, PhD, MCR, PT, Associate Professor of Neurology, School of Medicine at Oregon Health & Science University. “It’s important for them to see someone to help them get started, like a physical therapist who is familiar with PD.”
A recent study in The Lancet Neurology suggests that individuals who see physical therapists specializing in PD experience fewer complications related to the condition than those who visit physical therapists without that training.