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Vrksasana
tree pose This familiar pose builds strength and better balance.
FIRST Stand with your back near a wall to build confidence. With your feet parallel, spread your toes, and actively feel the floor under your feet. Stretch your legs straight. Bring the tops of your thighs back, and widen your sitting bones and upper thighs. Reach your hips back slightly, as if you were about to sit down in a chair. Then pull your tailbone down, firm your pelvic floor, and lift your lower abdomen. With your pelvis now directly over your legs, stretch down through your legs, up through your spine, and out through your arms, which are outstretched to the sides and lightly touching the wall. Bring the sole of your
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right foot onto the inner ankle of your left foot, and press it in firmly. You can keep your toes touching the floor lightly if you need to, or bring the entire right foot off the floor. Vigorously stretch your stand ing leg, your spine, and your arms. Embody the strength and dignity of a tall tree. Bring the top foot down, switch standing leg, and repeat on the other side. NEXT When you feel secure, increase the challenge as you stand away from the wall, bring the foot higher on the inner edge of your standing leg, and reach your arms overhead for as long as you feel comfortable.
remodeling. The rate at which bone remodeling happens is affected by how much calcium is stored in the bones and introduced in the diet, as well as by three catalysts (vitamin D, hormones, and exercise) that determine how effectively the body uses calcium to build new bone and prevent bone loss through resorption. Osteoporosis results from an imbalance in remodeling—where too much old bone is broken down and removed, or too little new bone is formed, or both. About 90 percent of an adult’s bone mineral content (calcium) is deposited by the end of adolescence, with peak bone mass achieved by age 20, says Kathy M. Shipp, an adjunct associate professor of physical therapy at Duke University School of Medicine who was a contributing author of the surgeon general’s 2004 report on bone health. Osteoporosis prevention begins in childhood with good health habits (such as proper nutrition and exercise), she notes. After about age 40, bone’s withdrawal period starts, and less bone is replaced during remodeling. For women, a drop in estrogen at the time of menopause leads to a more rapid and significant loss of bone mass. For men, a drop in testosterone—often beginning around age 70—can cause it. So will certain medications (notably steroids), medical conditions (such as rheumatoid arthritis and eating disorders), smoking, and excessive alcohol consumption.
maintenance plan
It’s not possible for adults past the peak growth years to add significant amounts of bone. (In the past, hormone replacement therapy was widely used to strengthen bones and reduce fracture risk in postmenopausal women until the Women’s Health Initiative study showed that it significantly increased the risk of breast cancer and stroke. There is also emerging evidence that vitamin D can be useful in significantly increasing bone strength.) But you can strengthen bones by exercising to maintain the bone mass you already have. “Bones get stronger from exercise by changing shape and by getting larger in diameter, even with the mass remaining constant,” says Shipp. “Progressive-resistance exercise [such as jogging, jumping, or walking], where you move your body or a weight against gravity while you remain upright, has been shown continued on page 88
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