Taking part in regular aerobic exercise could decrease the likelihood of developing Alzheimer's disease in adults who are at higher risk of generating the illness.

A study by a team at the Wisconsin Alzheimer’s Disease Research Center (ADRC), University of Wisconsin School of Medicine and Public Health, looked at the effects of exercise over a period of six months on individuals at risk for Alzheimer's due family history or genetic predisposition.

The study investigated cognitively normal, older adults with a family history or genetic risk for Alzheimer's.

All patients had a sedentary lifestyle and underwent a number of assessments, including cardiorespiratory fitness testing, measurement of daily physical activity, brain glucose metabolism imaging (a measure of neuronal health) and cognitive function tests.

Half of the participants were given information about maintaining an active lifestyle – but did not take part in organised exercise sessions.

The other half participated in a moderate-intensity treadmill training programme with a personal trainer, three times per week for 26 weeks.

Compared to the participants maintaining their usual level of physical activity, individuals assigned to the active training programme improved their cardiorespiratory fitness, spent less time sedentary after the training program ended, and performed better on cognitive tests of executive functioning (but not episodic memory).

The participants’ improved cardiorespiratory fitness was associated with increased brain glucose metabolism in the posterior cingulate cortex, an area of the brain linked to AD.

According to Ozioma C. Okonkwo, lead investigator at ADRC, the results could see exercise being incorporated into care plans against Alzheimer's.

“This study is a significant step toward developing an exercise prescription that protects the brain against AD, even among people who were previously sedentary,” Okonkwo said.

“The research shows that lifestyle behaviour – in this case regular aerobic exercise – can potentially enhance brain and cognitive functions that are particularly sensitive to the disease.

"The findings are especially relevant to individuals who are at a higher risk due to family history or genetic predisposition."

The results of this study are published in a special issue of Brain Plasticity devoted to Exercise and Cognition.

To read the full report, click here.