White matter: Why physical activity rewrites the brain after 50.
White matter — the brain's white matter — is not a passive cable between neurons. It's a tissue that movement can remodel, even in old age. A new longitudinal study from May 2026 tracked 715 adults. It revealed a simple, yet counterintuitive, finding: the brain doesn't just degrade with age; it reorganises. And physical activity drives this remodelling. Sounds like an Instagram slogan...
