Working out can be a double edged sword. You increase the oxidative damage by increasing your metabolism so it is imperative to take anti-oxidants. You tear up bone cartilage so you also have to increase your amino acid intake so your body has the raw materials to rapidly rebuild the tissue.
I work on people almost every day that were hardcore weight trainers and by thier 50's they have nearly destroyed thier joints. We have to look at our bodies as checking accounts and not write checks that our bodies can't cash.