Watch the Holding the Pick online guitar lesson by David Hamburger from Blues Guitar For Beginners
If you get deep into your practicing, you may not realize how long you've been hunched over in one position, using the same set of muscles over and over. Be careful! Try to unhunch slowly, rolling back your shoulders and gradually stretching out your arms to the side and loosening up your neck. Otherwise, you might tweak those muscles by moving too quickly and end up with a week's worth of Penguin Neck.