Do you have Parkinson’s disease and are currently able to walk without using any assistive device and are ages 50-74? If your answer to these questions is yes, you may qualify for our study. What will you do? You will wear activity monitors and a metabolic system; You will walk overground and on the treadmill. There is 1 lab visit that will last 2-3 hours. This study will advance the way we measure physical activity in people with Parkinson’s disease. Compensated with a $25 gift-card for participation. For more information, contact Jeffer on 205-975-9321 or via email enrl@uabmc.edu