God almighty, I may go on forever, be immortal! I walk 300kms a week, mostly pushing a lawnmower, all my life. Furthermore, I can work 100+ hrs a wk, ad finitum. There is TRUTH to this study. My advice, do as Nancy Sinatra, "these boots are for walkin" Well, I wear Merrill running shoes and German WW2 camo pants. Forgot, never been to a doc since I was 8.