Brain tissue may be fuel for marathon runners

November 2, 2023

Marathon runners appear to rely on myelin, the fatty tissue bundled around nerve fibers, for energy during a race, scientists report October 10 in a paper posted at bioRxiv.org. In the day or two following a marathon, this tissue seems to dwindle drastically, brain scans of runners reveal. Two weeks after the race, the brain fat bounces back to nearly prerace levels. The find suggests that the athletes burn so much energy running that they need to tap into a new fuel supply to keep the brain operating smoothly. SN