The Effect of Exercise in Water on Functional Fitness in People With Parkinson's Disease

The goal of this clinical trial study is to learn about the effect of aquatic exercise in parkinson\'s patients. The main questions it aims to answer are: * What is the effect of exercise in water on balance in parkinson\'s patients? * What is the effect of exercise in water on muscle strength in parkinson\'s patients? * What is the effect of exercise in water on flexibility in parkinson\'s patients? Parkinson\'s patients in this study will do some functional tests. One group of them will do exercises in water 3 times weekly for 8 weeks.