Is there a supplement or vitamin that helps with joint pain? My shoulders hurt when i do incline press and military press...

I tore my rotator cup will playing football in high school, so i have had share of dealing with shoulder pain. I have tried taking Glucosamine Sulfate. I have had mixed results with it. The biggest improvement in reducing the pain in my shoulder is to have a stricter form. Use the heaviest weight you can use but dont substitute higher weight for improper form. I have also noticed with stricter form that I have actually made alot better gains.

Another suggestion might be to take a week or two off. Every so often I take a week off to allow my body time to recover after months of continous pounding. Not only does this give my body extra time to rest but it also increases my motivation. That week off feels like a year to me. So, I'm very motivated when I return to the gym.

I hope this helps.

This is probably a rotator cuff problem, it is doubtful that a supplement is going to help much. This problem is very common. My recommendation would be: Stop doing military press (your front delts get enough stimulation from benching movements to begin with) and use dumbbells for incline press. Also take it easy on the weights for a while and ice the area every now and then. There are also some exercises you can do to help with healing. Such as these ones:

http://www.aafp.org/afp/20030315/1315ph.html