CHICAGO, Dec. 15 (Xinhua) -- High-intensity exercise three times a week is safe for individuals with early-stage Parkinson's disease and decreases worsening of motor symptoms, according to a multi-site trial led by researchers from Northwestern Medicine and University of Colorado School of Medicine.
The randomized clinical trial included 128 participants aged 40 to 80 years old. Participants enrolled in the Study in Parkinson Disease of Exercise (SPARX) were at an early stage of the disease and not taking Parkinson's medication, ensuring the results of the study were related to the exercise and not affected by medication.
Researchers examined the safety and effects of exercise three times weekly for six months at high intensity, 80 to 85 percent of maximum heart rate, and moderate intensity, 60 to 65 percent of maximum heart rate. They compared the results to a control group who did not exercise.
After six months, participants were rated by clinicians on a Parkinson's disease scale ranging from 0 to 108.
Participants in the study had a score of about 20 before exercise. Those in the high intensity group stayed at 20. The group with moderate exercise got worse by 1.5 points. The group that did not exercise worsened by three points. Three points out of a score of 20 points is a 15 percent change in the primary signs of the disease and considered clinically important to patients. It makes a difference in their quality of life.
"We are stopping people from getting worse, which is significant, particularly if we catch them early in the disease," said Daniel Corcos, professor of physical therapy and human movement sciences at Northwestern University Feinberg School of Medicine.
"The earlier in the disease you intervene, the more likely it is you can prevent the progression of the disease," Corcos said. "We delayed worsening of symptoms for six months; whether we can prevent progression any longer than six months will require further study."
This is the first time the effects of high-intensity exercise on patients with Parkinson's disease have been tested. Parkinson's disease is the second most common neurodegenerative disorder and the most common movement disorder, affecting more than a million people in the United States.
The study has been published Dec. 11 in JAMA Neurology.
