Ok I've got a strange problem I come in one day with a light warm up and I'm benching 350 like its nothin a few days later I come in and I'm weak as hell the weight from 135 even hurts. One day I'll come in and do a few sets of 20 with 225 and the next training session I'm fighting for a rep of 10. My muscles ache from what should be warm ups for me. This doesnt happen very often but its more often than what I want it to happen. My diet doesnt change, I stretch and have tried diffrent things but I usually just call it quits for the day. My question is what is causing this? Does anyone else have this problem? I really feel its more than just having an "off day". I'm thinking I might have some type of defecincy or reaction to something in my diet but my deit doesnt seem to change.