Exercise interventions to minimise bone and muscle loss in obese older adults

Associate Professor David Scott is exploring exercise interventions to improve the health of older adults, of whom up to 40 per cent are obese and suffering significant disability and poor health.

In older adults with obesity, losing weight is the best way to reduce the risk of chronic diseases, such as heart disease and diabetes.

But a negative side effect of losing weight is the accompanying loss of bone mass (osteoporosis) and muscle mass (sarcopenia) that in turn may increase the risk of fractures.

Supported by an NHMRC Investigator Grant, Associate Professor David Scott’s program of research explores several themes related to obesity in older adults.

Associate Professor Scott will conduct specific exercise interventions in obese older adults who are losing weight through diet and also weight loss surgery, to determine whether bone and muscle loss can be minimised.

The exercise interventions, designed for both gym and home settings, will involve weight-lifting and ‘impact’ (hopping and jumping) exercises which are known to be beneficial for bone and muscle health. The final part of his research program focuses on using technology to prescribe and monitor impact exercise in the home environment.

“We are delivering individually-tailored home-based exercise programs to patients using telehealth systems, and we are also developing a wearable device which will enable us to measure impact achieved through hopping and jumping exercises,” Associate Professor Scott said. 

“This device will give us the information we need to make sure the exercise prescriptions we provide to older adults will benefit their bone health while avoiding potential joint pain and damage.”

Associate Professor Scott said almost 40 per cent of our older adult population were now obese.

“Contrary to popular belief, obesity itself is not associated with early mortality in this age group,” he said.

“This means we have a large population of older adults who are spending many years towards the end of their life with poor health and physical function. Evidence-backed exercise interventions will offer prolonged independence to people in this age group.

“As a result, more older adults will be able to spend more years of their life with the capacity to work, socialise with friends, and play with their grandchildren.”

Associate Professor Scott’s project builds on his previous research, which has demonstrated that older adults who lose weight over several years only appear to have increased risk of fracture if that lost weight comprises a relatively high amount of muscle mass compared to fat mass.

“This has informed our approach where we want to add targeted exercise training to weight loss to ensure that as much muscle mass as possible can be maintained,” he said.

Associate Professor Scott hopes his research will lead to new guidelines for management of obesity in older adults both in Australia and overseas, as well as the development of accessible programs and tools that can encourage and support older adults to take greater control over management of their own health.