Of all the lifestyle changes that have been studied, taking regular physical exercise appears to be one of the best things that you can do to reduce your risk of getting dementia according to the Alzheimer’s Society.
Several studies looking at the effect of aerobic exercise (exercise that increases your heart rate) in middle-aged or older adults have reported improvements in thinking and memory, and reduced rates of dementia.

Exercising in mid-life
Prospective studies follow the health and behavior of a group of people over time. Several prospective studies have looked at middle-aged people and the effects of physical exercise on their thinking and memory in later life. Combining the results of 11 studies shows that regular exercise can significantly reduce the risk of developing dementia by about 30 per cent. For Alzheimer’s disease specifically, the risk was reduced by 45 per cent.