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Some of the first work on bone health in Arizona started in 1984 by physiology Professor Timothy Lohman, who established the Body Composition Laboratory. This lab assessed bone development and associations with physical activity, nutrition, and exercise training. Since then, the UA research team has explored bone development in young girls, athletes, pre- and postmenopausal women and have developed exercise and nutrition recommendations for achieving maximum bone density.

Deterioration of bone tissue and low bone mass are symptoms of the disease osteoporosis. "The cost to the community is estimated to increase to between 20 and 40 billion dollars per year unless effective prevention strategies are found," says Going. Statistics reveal that Arizona has some of the highest rates of osteoporosis nationwide, with 810,000 diagnosed cases to date. The high rate is attributed to the state's growing number of retirement communities and their aging residents.

In 1989, Going, Houtkooper, and Lohman began looking at trends in women's health care. One of the first things they discovered was that not much was known about the effects of exercise and calcium on bone health of pre-menopausal women (28-38 years old) and whether increased exercise and adequate calcium in the diet may help prevent bone loss at menopause. "This was a new frontier in research with women," says Houtkooper.

The researchers initially studied groups of pre-menopausal women and most recently post-menopausal women to test their theories on preventing, slowing, and even reversing bone loss. While other factors such as genetics, diet, smoking, and hormone-replacement therapy play a role, the findings indicate that weight-bearing and progressive-resistance (weight lifting) exercise three times a week can make a difference.

One challenge was not being able to see what was happening under the skin and through muscle and bone. Over the years, work evolved on new methods of estimating how much fat, bone, and muscle are in the human body and how physical activity slows the aging process. This led to the invention of Dual Energy X-ray Absorptiometry (DEXA), which using body scans to provide a method of assessing body composition over time.

Because women approaching or in menopause are often thinking about hormone replacement therapy, which has been shown to increase bone mass, researchers had questions. "We wanted to know if it was it all about hormones, or could exercise play a role?" Going says. The research team looked at multiple-intervention strategies. The desired research subjects were sedentary, post-menopausal (naturally or surgically induced), non-smoking women.