, scientists posit that marathon runners' bodies might turn to brain tissue as a mid-race energy source, gobbling down the mind's protective myelin layer and turning it into fuel.
In other words, they were widely thought to be unchanging structures with a single job to do. But according to the paper, published in early October as a preprint, before-and-after scans of a handful of marathon runners' brains tell a different story: that myelin is a dynamic and adaptable tissue that's not only available to the body as a reserve energy source during prolonged physical exercise, but also as aThe study itself is fairly simple.
"This is definitely an intriguing observation," neuroimaging scientist at the National Institute on Aging in Baltimore Mustapha Bouhrara, who was not involved in the study, toldof the research. "It is quite plausible that myelin lipids are used as fuel in extended exercise."