Just five minutes of exercise a day can reduce the risk of dementia in frail older people by more than a third, according to new research. The analysis of exercise levels among 90,000 adults found that engaging in as little as 35 minutes of “moderate to vigorous” physical activity per week was associated with a 41pc lower risk of developing the

A study by Johns Hopkins Bloomberg School of Public Health researchers found that five minutes a day of light exercise may help prevent dementia, even for frail older adults. A doctor weighed in.