Dear Linda: Thanks for the reply. You may be right on the off and on;that was the first and only time that it has been so definitely "off." I will try the boost idea next time I am confronted with it. Riding sounds like a good idea; glad it works. In my last note on the network, I mentioned Feldenkreis and noted a book by Jack Heggie on running. His approach to the process and the exercises would be very helpful to us with PD walking; the name of the book is a bit of a misnomer. You might look at it. It would be really useful to get some direct attention from a Feldenkreis practitioner, since the experience of a person goes far beyond what they can tell you in a book. Good luck with the diagnostic process. I have nothing to offer there. Regards, Bob N.