Would glucosamine chondroitin really work for a man in his 40's who works out with shoulder joint pain?

You can try, but...: Glucosamine and chondroitin are supplements that some believe help osteoarthritis pain; studies have shown mixed results; the american academy of orthopedic surgeons recommend against routine prescription of these for knee oa; they have not been well studied for shoulder arthritis; see a sports med doc to get a diagnosis (you may not have oa)-that will help guide you toward optimal treatment.

If you have OA.: The combination of glucosamine and chondroitin has been shown in studies to (1) provide a degree of pain relief in the short term, and (2) trigger growth of new cartilage when taken for at least two years straight. So it can help you pain and reverse some of the chronic damage. You can find this in the health food store. If you have arthritis, it may help.

No: Totally worthless. Save your money and do regular exercise for the most benefit.