The study found that high-intensity exercise improved tremors and slowed the progression of symptoms. Symptoms of the disease did not change or improve significantly for most of those who took part in the high-intensity exercise. Participants in the moderate-intensity exercise group saw their symptoms worsen by 7.5%, while symptoms of those in the control group worsened by 15%. Medicines that stimulate dopamine are currently standard treatment but can cause unwanted, uncontrolled movements, called dyskinesia, as the disease progresses.