Taking part in the right amount of moderate to vigorous physical activity could slash a person’s risk of experiencing dementia, stroke, anxiety, depression and sleep disorders by up to 40%, a study suggests.

Researchers analysed data from more than 73,000 people in the UK who wore accelerometer devices to monitor their movement for seven days.

The devices also measures how much energy they used and how much time they spent sitting down each day.

Physical activity was measured in metabolic equivalents (METs), with moderate to vigorous activities defined as those measuring at least three METs.

For example, walking or cleaning counted as three mets and more intense exercise such as cycling could be six, deepening on the speed.

The analysis found that people who did more moderate to vigorous physical activity were between 14 and 40% less likely to develop one of the three diseases.

People who did not develop any of the diseases had an average daily moderate to vigorous physical activity energy expenditure of 1.22 kilojoules per kilogram, compared to 0.85 for the people who developed dementia, 0.95 for those who developed sleep disorders, 1.02 for stroke, 1.08 for depression and 1.10 for anxiety.

Those who spent the most time sitting were also up to 54% more likely to be diagnosed with one of the conditions.

Study author Dr Jia-Yi Wu, of Fudan University in Shanghai, China, said: “This research highlights the role of physical activity and sedentary behaviour as modifiable factors that may enhance brain health and reduce the incidence of these diseases.

“It is promising to think that encouraging people to make these lifestyle changes could potentially lessen the burden of these diseases in the future.”

Dr Wu added: “Some previous studies have relied on people reporting on their own levels of activity.

“With our large number of participants and the use of devices that provide objective measurements of activity levels, these results will have implications for assessing risk factors and developing interventions to prevent the development of these diseases.”

Researchers noted that 96% of study participants were white, which may mean the results do not apply to people from other backgrounds.

The findings will be presented at the American Academy of Neurology's 77th Annual Meeting in April.