I'm not a runner- my boobs make it a very uncomfortable experience for me- even in a shock absorber bra!! I've walked it a couple of times though!! However, this year I'm going to do a 22 mile walk for Macmillan instead, which takes place on 11th September on the Gower peninsula where I live (near Swansea). I feel that if I'm going to walk anyway, I may as well make it a long one, and I'm really into walking at the moment- I love it!!X