I've been looking around this thread and tried using the search bar but i couldn't get much on this subject. I've been combining certain muscle groups with others in one workout eg: chest and tri's and other different combinations, trying to keep my body guessing. (sometimes it really hurts trying to give enough rest inbetween each muscle group.) I think that now i'm starting to plataeu. I was wondering what you guys thought about working only one muscle group a day hence giving lots of rest for each muscle group. Any inout?