Possible Duplicate:
What can I do to minimize damage to my picking hand wrist as I practice guitar?
I've heard of many musicians having problems with carpal tunnel and tendonitis, and now some of my friends are even dealing with mild cases (one of them is even less than 17 years old). How can injuries of this type be prevented? What types of stretches of should I look at to protect myself from injury?
I want to be able to enjoy a lifetime's worth of making music, so I'm eager to make sure my body is able to handle it as well.
NOTE: I think this question is fairly instrument-agnostic as nearly all instruments involve repetitive motion, but it could be split up for specific groups of instruments if necessary. I know this is a health topic, but I think it's highly relevant to virtually all musicians.