Here's a stretch to work one hamstring at a time. You'll feel this in your lower back, too, and it'll also begin to open your hips.
- Sit on the floor with both legs extended in front of you. Bend your right knee and pull the sole of your foot against your left inner thigh.
- Reach your right hand to the outside edge of your left foot so you can stack your torso directly on top of your left leg. Bring your left hand to the arch of your left foot. If you can't reach your hands to your foot, then reach out as far as you can, resting your chest on your left thigh. Remember, the point here is to stretch your hamstrings, hips, and lower back, not to touch your foot.
- Stay here for five breaths, relaxing your shoulders away from your ears. Then do the other side.