as a "foot"note (man can ya tell I rode at lunch?)
I can't help you with the stress fracture question, I've never heard of a sprain or strain causing a stress fracture - but then I've never heard of a lot of things! BUT, what I can do is give you a GREAT exercise to help strenghten your ankles that the PTs gave me when I broke mine - both at 2 seperate times.
Stand in a doorway holding on to both sides of the door frame. Lift one leg, close your eyes and let go of the door frames. Count as far as you can until you lose your balance (using the door to catch you). Try and hold the one-legged, closed-eye stand for a count of 30. Switch legs and repeat.
I know, ya'll are probably laughing now but when you close your eyes, you lose your horizon reference which changes your balance. By standing on 1 leg, you have to use your ankle to support your torso. Try it.......the first time I did I couldn't hold it for more than 3 seconds. Even now 10 yrs later there are still times I can't make it to 30.
Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, champagne in one hand, strawberries in the other, body thoroughly used up, totally worn out and screaming: "Yeah Baby! What a Ride!"