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Can exercise during childhood protect you against memory loss many decades later? Exercise early in life seems to have lifelong benefits for the brain, in rats at least.

“This is an animal study, but it indicates that physical activity at a young age is very important – not just for development, but for the whole lifelong trajectory of cognitive development during ageing,” says Martin Wojtowicz of the University of Toronto, Canada. “In humans, it may compensate for and delay the appearance of Alzheimer’s symptoms, possibly to the point of preventing them.”


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Wojtowicz’s team spilt 80 young male rats into two equal groups, and placed running wheels in the cages of one group for a period of six weeks. Around four months later – when the rats had reached middle age – the team taught all the rats to associate an electric shock with being in a specific box. When placed in the box, they froze with fear.

Two weeks later, the team tested the rats in three scenarios: exactly the same box in the same room, the same box with the room arranged and lit differently, and a completely different box in a different room.

The rats without access to a running wheel when they were young now froze the same proportion of times in each of these situations, suggesting they couldn’t remember which one was hazardous. But those that had been able to run in their youth froze 40 to 50 per cent less in both altered box settings.

“The results suggest the amount of physical activity when we’re young, at least for rodents, has implications for brain and cognitive health—in the form of better memories—when we’re older,” says Arthur Kramer of Northeastern University in Boston, who has found that, in humans, exercise stimulates the growth of new brain cells.

Journal reference: eNeuro, DOI: 10.1523/ENEURO.0237-17.2017

This article will appear in print under the headline “Young runners remember better when old”