Soccertese, you want to be sure to have your heart rate at 60-80% of your maximum rate. Maximum rate = 220 - your age. I get foot dystonia too, but I get a strong sense that everyone's is different and easier or harder to cope with. I just returned from 25 miles at 44 degrees and wind. My foot went south at about 12 miles, but I was paying too much attention to the headwind, chill factor and impending rain to let it slow me down. Maybe I speeded up just to get home! My dystonia can't be as bad as some of you endure.