I agree with the fact that stretching is very important if not more important. Have someone doe a postural assessment on you and you will have your answers on what muscles are affected. I have been involved in bodywork for 5 years through both Massage and Physical therapy. So posture and bodymechanics have been vital in my survival. But even so, by working many hours, and also doing being on the computer often, you can see that my anatomy has been affected. So whenever I remember to I stretch them out including in between clients. My pecs are tight, so I have IR at the shoulder, tight scalines, upper traps and L-scap, my forearms are pronated and my wrists are in extension... all because of overuse and compensation. But to also counteract the long term effects of my posture, I do workout to try and strengthen the aneforum.xxxonistic muscles. That way I am assisting in the fight against the muscles contracting into the postitions that I am working in. I was actually sore when I came back from my vacation after not massaging for 2 weeks!!! Because my body wasn't used to not working!