In an article below titled "The Weight Training" I made reference to some rotator cuff exercises. If you do not have a back ground in anatomy/physiology you may not have an idea what I am actually talking about. The rotator cuffs help to stablise the shoulder by drawing the arm into the joint socket. Imbalances in these muscles may lead to impingment issues and inflammation.
The topic itself deserves a number of dedicated articles which I will write up soon. For now I have found a few videos which describe some appropriate exercises quite well. Enjoy!
As a strong advocate for core stability and it's applications in sport I recommend performing a simple pilates routine 4-6 times per week. Some yoga or stretching will also help to open up those tight muscles. I have found a number of YouTube videos to be helpful in this area and will post some links in below: