Man, I always forget which one. My lower back is sore as hell (not injured, just sore). I've been doing 5x5's for DL, squats and bench. The DL's are killing me and the squats don't help either. My back has been sore for a couple of weeks straight now. And being hunched over making that sand bag and farting around with it didn't help either. So is it ice or heat and how often?