How best to run away from osteoporosis

Two-minute dashes strengthened the bones of women

Denis Strigun, Naked Science

Osteoporosis manifests itself in a decrease in bone strength. The risk of a violation is increased by many factors, including old age and gender: it is detected much more often in women than in men, especially after menopause. It is assumed that regular exercise can reduce the likelihood of illness. But unlike the prevention of cardiovascular diseases (150 minutes a week with approaches of 10 minutes at moderate exercise), the intensity and frequency of exercises optimal for stimulating bone metabolism are unclear. Insufficient efforts will be ineffective, and excessive efforts can lead to the opposite effect – a decrease in bone mass – or injury. The authors of the new work have filled this gap.

To do this, scientists examined the cases of 1,218 healthy women before and 1,316 after menopause, data on which were contained in the Biobank UK (UK Biobank). For six days, including a day off, they wore a wrist accelerometer. Thus, the researchers obtained statistics of total physical activity, with the help of which they calculated the average daily values. Bone mineral density was measured by an ultrasound osteodensitometer on the calcaneus and then compared with sensor readings. The comparison was carried out on the basis of the 2014 work: according to it, moderate and high load corresponds to the values of the accelerometer 100 and 400 milli-g, respectively.

The authors of the new article adapted these values taking into account the strength of the normal reaction, optimal for the bone. As a result, they took 750 and 1000 milli-g for the threshold (about three to six MET – metabolic equivalents), which are approximately comparable to jogging - at a speed of eight and ten kilometers per hour, respectively. Separately, the scientists examined the dynamics of changes in the activity intervals of 50-99, 100-749 and 100-999 milli-g. Subsequent modeling showed that bone density in women before menopause increased statistically significantly at the highest loads, and the effect was observed only for approaches whose duration was at least one minute.

On the contrary, after the onset of menopause, loads of slightly lower intensity – 750 milli-g - were better associated with the strength of the skeleton. The trend was also associated with a certain duration of exercises: they had to exceed one minute. In both groups, the increase in tissue mineral density reached four and six percent for one to two and more than two minutes, respectively. According to the researchers, the data obtained indicate that short and high loads seem to be more useful for bones than long, but moderate ones. However, it is not known how the frequency and number of such approaches per week correlate with the indicator. It is planned to clarify this in future works.

Article Stiles et al. A small amount of precisely measured high-intensity habitual physical activity predicts bone health in pre- and post-menopausal women in UK Biobank is published in The International Journal of Epidemiology.

Portal "Eternal youth" http://vechnayamolodost.ru  19.07.2017