Some old fart (76 years young) that claims to be my Dad switched from jogging to cycling in his late 50's to help with the diabetes after the joints started aching too much. Until a couple of years ago - he'd do several C's a year (came down with the shingles - and he hasn't been able to get the endurance back since then). I think it was 11 years in a row he did the Hotter N Hell.

He swears by Fig Newtons, Peanuts, and plain o' H2O. Claims the fancy power bars and power drinks make his blood sugar swing up and down too much.