Forward bends have a calming effect on the nervous system and are generally done at the end of yoga practice.

Begin seated on the floor with your legs straight in front of you, feet flexed. Bend your right leg and place the sole of your right foot against the left inner thigh, like a seated tree pose.

Turn your torso slightly so that your navel is pointing toward the leg. Inhale and lengthen up and out from your hips and fold over the leg as you exhale. If you can reach your foot, take hold of it and press it into your hands, engaging the leg. This will protect the hamstring.

Think of extending as you inhale and releasing as you exhale. Although the Sanskrit name of the pose means head to knee, it's more important to have length in your spine than to force your head down to your knee. Switch legs and repeat on the other side.