Travis_Bickle Have you considered yoga, or other martial arts? They focus a lot on stretching, core strength, flexibility and trying to warm up all muscle groups to keep injuries to a minimum. I don't think I would be running without the martial arts, or vice-versa, to be honest. Back problems are something I haven't suffered from very much, which I think is down to the martial arts stuff, but I don't want to jinx it.