Running an entire marathon takes a lot of energy. Neuroscientist Carlos Matute knows this: he's run 18 of them. He wondered how runners' bodies get the energy they need to make it to the finish line.
His new research in the journal Nature Metabolism may be the first step in answering the question – and suggests their brains might be (temporarily) depleting a fatty substance that coats nerve cells called myelin.
Myelin makes up about 40% of the brain. It helps electrical signals travel around. After scanning the brains of 10 marathon runners, Matute and his team saw that myelin decreased in areas important for things like motor coordination – how we move our bodies – and sensory and emotional integration.
The changes were temporary – so runners, no need to panic – but Matute thinks the study could be a step towards understanding conditions like multiple sclerosis, where myelin decreases in the brain and typically doesn't return.
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This episode was produced by Berly McCoy and Mia Venkat. It was edited by Geoff Brumfiel and Christopher Intagliata. Tyler Jones checked the facts. Kwesi Lee and Jimmy Keeley were the audio engineers.
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