London: Any physical activity that gets the heart pumping may reduce the risk of dementia and slow the condition's progression once it starts, a new study has found.

Researchers at Mayo Clinic in the US examined the role of aerobic exercise in preserving cognitive abilities and reached a conclusion that it should not be overlooked as an important therapy against dementia.

The researchers broadly defined exercise as enough aerobic physical activity to raise the heart rate and increase the body's need for oxygen. Examples include walking, gym workouts and activities at home such as shovelling snow or raking leaves, the Daily Mail reported.

Study researcher Eric Ahlskog said: "We culled through all the scientific literature we could find on the subject of exercise and cognition, including animal studies and observational studies, reviewing over 1,600 papers, with 130 bearing directly on this issue.

"We attempted to put together a balanced view of the subject. We concluded that you can make a very compelling argument for exercise as a disease-modifying strategy to prevent dementia and mild cognitive impairment, and for favourably modifying these processes once they have developed."

The researchers, who detailed their findings in journal Mayo Clinic Proceedings, noted that brain imaging studies have consistently revealed objective evidence of favourable effects of exercise on human brain integrity.

Also, they said, animal research has shown that exercise generates trophic factors that improve brain functioning, plus exercise facilitates brain connections (neuroplasticity).

More research is needed on the relationship between exercise and cognitive function, the authors said, but added that exercise should be encouraged in general, especially for those with or worried about cognitive issues.

(Agencies)