Washington, Aug 10 (IANS) Getting older by the day and you feel you're forgetting things? A bit of muscle flexing could help you, says a new research.

The findings suggest moderate exercise may modify the brain to boost its ability to protect itself during ageing, when it is particularly vulnerable.

Researchers led by Ruth Barrientos, University of Colorado, Boulder, found older rats experienced memory loss following a bacterial infection, an outcome not seen in young adult rats.

But they found them recovering from memory loss if they ran just about half a kilometre each week.

In humans, older adults are more likely than the younger ones to suffer memory impairment following severe bacterial infection or injury, reports The Journal of Neuroscience.

"This is the first study to show that exercise reduces susceptibility to the cognitive impairments that follow infection in ageing animals," said Barrientos, according to a Colorado statement.

Bacterial infections kick off a cascade of events that signal to the brain that something is wrong.

They also found immune defence cells in the older animals's brains became more reactive to infection, releasing more chemicals involved in inflammation in the hippocampus (inside the brain), as compared with younger animals.

"This study provides exciting evidence that a little moderate exercise is protective against age-related problems with health and immunity," said Jonathan Godbout, an expert on ageing at Ohio State University, not affiliated with the study.