This seated spiral twist will strengthen and stretch your spine, but a common mistake is to round your back, which causes your chest to cave in. If this happens to you, try elevating your hips on a yoga block. You will find it easier to sit up straight and perform the exercise correctly.
Sit cross-legged on a yoga block or on the edge of a thick blanket with your right leg in front. Rest your hands on your legs. Inhale and lift your chest, pull your abdominals toward your spine and relax your shoulders down and away from your ears.
On an exhalation, rotate your rib cage, chest, shoulders and head to the right. Place your left arm across your right outer thigh to increase your range of motion. Be sure your hips don't twist and you can feel the stretch in the mid-back. Pause for three to four breaths. Then return to center, change the cross of your legs and repeat on the other side.
Voight is the creator of a line of fitness DVDs, including "Full Body Stretch" and "Ballet BodySculpt."