Five 15-Minute Workouts
What they do: Warm up the muscles along the spine; stretch the hips, back, abs, shoulders, and neck.
How to do them: Start on your hands and knees. For cow (shown), arch your back and press your shoulders down and back, away from your ears, and open your chest. For cat, round your back, lower your head, lift your belly, and look at your thighs. Try to create space between your shoulder blades.