Parkinson's disease is a progressive neurological condition that affects movement and is caused by a reduction in dopamine-producing cells in the brain. Common symptoms include slowed movements, muscle stiffness, tremor, reduced balance, and changes in walking such as shuffling steps or difficulty initiating movement. People with Parkinson's disease may also experience fatigue, changes in posture, reduced coordination, and challenges with daily activities. Although Parkinson's disease is progressive, exercise and rehabilitation play an important role in maintaining mobility, function, and independence.