In April 2019 researchers from the UK published the results of their study to assess the effect of both a sedentary lifestyle and regular physical activity on bone strength. A total of 214 individuals (92 men, 112 women; aged 62 years) were involved in the study. Information on physical activity and sedentary time was collected via an accelerometer over a 4-day time period. In addition, each individual had their bone mineral density assessed. Results showed that men led a more sedentary life than women, and a higher sedentary time was associated with a reduced bone mineral density. In fact it was seen that every 84 minutes sedentary time corresponded to 0.268 g.cm-2 reduction in bone mineral density. In contrast, light physical activity and steps/day resulted in a higher bone mineral density in both sexes. In women, an increased number of steps/day was associated with a higher bone mineral density, with a difference of 1415 steps/day corresponding to 0.232 g.cm-2 increase in bone mineral density.
Hind K et al. Objectively-measured sedentary time, habitual physical activity and bone strength in adults aged 62 years: the Newcastle Thousand Families Study. J Public Health (Oxf). 2019 Apr 24. pii: fdz029. [Epub ahead of print]