With this pose, you'll build strong abdominal muscles that will support your lower back. Your legs will need to be very flexible, so you might have to keep your knee bent for a while. In this pose, it's more important to straighten your back than to fully straighten your leg.
Sit cross-legged on a padded surface or a mat. Bring your right knee toward your chest and hold the sole of your right foot with both hands. Inhale, sit up tall and move your knee toward your chest without rounding your back or collapsing forward. Pause for a few breaths while feeling a stretch in the back of your right thigh.
Continue to keep your chest and back lifted as you slowly straighten your right leg as far as you can. Balance on your buttocks, drawing your shoulder blades down and into your chest (don't let your shoulders rise up toward your ears). Hold this pose for three to six breaths, keeping your breath relaxed. Release your leg and repeat on the other side.
Voight is the creator of a line of fitness DVDs, including "Sleek Essentials."