Doing lots of exercise in older age can prevent the immune system from declining and protect people against infections. Scientists followed 125 long-distance cyclists, some now in their 80s, and found they had the immune systems of 20-year-olds. The research was published in the journal Aging Cell.

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Doing lots of exercise in older age can prevent the immune system from declining and protect people against infections. Scientists followed 125 long-distance cyclists, some now in their 80s, and found they had the immune systems of 20-year-olds. The research was published in the journal Aging Cell.