Popular sport named brain killer - Unexpected scientific findings

Marathon running is a popular way to stay in shape, but a new study published in Nature Metabolism has revealed potentially concerning consequences for the brain. Scientists have discovered that during prolonged exertion, the brain may consume its own resources, including myelin - a fat-like substance that covers neurons and ensures their normal functioning.

During a marathon, when glucose reserves are depleted, the brain begins to use alternative energy sources. Research by Spanish scientists has shown that at this point, myelin itself may be utilized, which can temporarily reduce brain functions. Areas responsible for movement and emotions are especially affected.

The experiment was conducted with 10 marathon runners. Their brains were scanned using MRI before the race, immediately after, as well as two weeks and two months later. A decrease in myelin levels was recorded 48 hours after the marathon, but after two months, the indicators returned to normal.

Although the changes proved to be reversible, scientists warn: for people with certain diseases, such as ALS, such exertion can be dangerous. In their case, the destruction of myelin may worsen the course of the disease.

Overall, the study suggests that healthy people can continue to participate in marathons without risk to the brain - provided they take a sensible approach to training and recovery.