There was a suggestion concerning "deep water running" using a floatation device as a means for developing physical fitness. In general I think its a great form of exercise. There is no scientific evidence that it will help or hurt people with PD. The only reservation I would have is that people who cannot swim should not be doing deep water running, inspite of wearing a floatation vest for bouyancy. For them water walking may be a better alternative. It's a good idea to consult the local red cross if they offer these classes in your community...they have qualified instructors who know what they are doing and thats also important, isn't it? Mark Hirsch, Ph.D. Johns Hopkins