A so-called 'new' study suggests that getting regular weight-bearing resistance exercise and taking plenty of calcium can help maintain bone density, at least in the hip, without taking HRT. The research was published in Jan. 2003, but issued as a press release on Sept. 30, 2005.
The study simply concluded that bone mineral density in post menopausal women can be increased by certain kinds of exercise combined with high calcium consumption. It did not conclude that this helps keep osteoporosis at bay.
Doctors have known for a long time that high impact exercise and calcium supplements do indeed increase bone density. This very short-term study (just one year) simply confirms other studies showing that bone mineral density increases with high impact exercise and calcium supplements. But this comes at a terrible price. As explained in The Milk Imperative ( www.milkimperative.com ), when you increase bone density in this manner, you increase the risk of osteoporosis later in life. This is so, because by increasing bone density you use up bone-making cells and deplete the bodys finite capacity for making new bone, thus speeding up the onset of osteoporosis.
To see the full text of the study go to Weight Lifted in Strength Training Predicts Bone Change in Postmenopausal Women, Medicine & Science in Sports & Exercise. 35(1):10-17, January 2003.