Photo credits: James Michelfelder.
1. Hold the bar (alternatively, you can use a pair of dumbbells) overhead with an overhand, shoulder-width grip and lie back on the floor.
2. Press the bar over your head and then reach back over your head, bending your elbows only slightly. Continue until you feel a stretch in your lats, and then pull the bar back over your chest, flexing your triceps as you go.