Women who run a single minute a day have better bone health than those who run less than a minute, say scientists from the U.K.'s University of Exeter and the University of Leicester.

The researchers found women who did "brief bursts" of high-intensity, weight-bearing activity equivalent to a medium-paced run for pre-menopausal women, or a slow jog for post-menopausal women, had better bone health, which reduces the risk of osteoporosis and fractures in older age.

"We don't yet know whether it's better to accumulate this small amount of exercise in bits throughout each day or all at once, and also whether a slightly longer bout of exercise on one or two days per week is just as good as 1-2 minutes a day," said lead author Dr. Victoria Stiles, of the University of Exeter.

The researchers compared activity levels (measured by wrist-worn monitors) with bone health (measured by an ultrasound scan of heel bone).

Women who on average did 60-120 seconds of high-intensity, weight-bearing activity per day had 4 percent better bone health than those who did less than a minute. Bone health was 6 percent better in those who exercised for more than two minutes a day.

Along these same lines, a recent Irish study which examined the relationship between dairy intake and bone density, found that the hip bones of senior citizens who ate the most yogurt were denser than the hip bones of those who ate the least. After adjusting for all risk factors, women who ate the most yogurt  had a 39 percent lower risk of osteoporosis and men a 52 percent lower risk when compared to those who ate the least yogurt.

These studies become even more significant in light of a recent study which found that bisphosphonates, which are sometimes used to treat osteoporosis, do not appear to prevent fractures in women who take them for more than 10 years. They include popular prescription drugs such as Boniva, Fosamax Plus D, and Reclast.

The study, which was published in the Journal of the American Geriatrics Society, examined women with a high risk for bone fractures who used bisphophonates. They discovered that women who took them for 10 to13 years had higher fracture rates compared with women who took the medications for two years.