Intense Physical Activity Cuts Parkinson's Risk
Strenuous Exercise Lowers Risk for Men but Not Women, Study Finds
Feb. 24, 2005 -- Physical activity may lower the risk of developing Parkinson's disease, a new study shows.
Parkinson's disease occurs when certain nerve cells in an area of the brain (substantia nigra) die or become impaired. These cells produce a chemical known as dopamine, which helps direct and control muscle movement.
Parkinson's cause has not been identified. While no cure currently exists, treatment including drug therapy and/or surgery can manage symptoms, which include tremors, stiff muscles and achiness, and problems with balance, posture, and movement.
The average age at which it is diagnosed is 60. However, about 10%-20% of those diagnosed with Parkinson's disease are under age 50, and about half of those are diagnosed before age 40. When the diagnosis is made early, it is referred to as "young-onset" Parkinson's disease.
The new study appears in the journal Neurology's Feb. 22 issue. It's the work of researchers including Alberto Ascherio, MD, DrPH, associate professor of nutrition and epidemiology at the Harvard School of Public Health in Boston.
Participants included more than 48,500 male health professionals and more than 77,000 female registered nurses. At the study's start in 1986, the men were 40-75 years old and the women were aged 40-65 years.
Starting in 1986, participants filled out questionnaires about their physical activity every two years. They reported how much time they spent per week walking or hiking outdoors; jogging; running; bicycling; swimming laps; doing calisthenics, aerobics, or aerobic dance; using a rowing machine; or playing tennis, squash, or racquetball. They also estimated the number of flights of stairs they climbed per day.
By 2000, a total of 252 men and 135 women developed Parkinson's disease. Men were about 69 years old and women were nearly 65 when symptoms were first noticed.
Physically active men had a lower risk of Parkinson's disease. "In men, overall physical activity was inversely associated with Parkinson's disease risk," write the researchers.
How Do Results Differ for Men and Women?
Strenuous activity, but not moderate activity, was the key. "A 50% risk reduction was observed when comparing men in the highest category of vigorous physical activity vs. those in the lowest [category]," write the researchers.