When athletes engage in prolonged endurance activities like marathons, their brains may resort to “eating” its own fatty tissue for fuel. According to a recent pilot study, the brain’s myelin sheath, which helps neurons send messages efficiently, can be reused and recycled when glucose levels are low.
Researchers analyzed the brains of 10 marathon runners before and after their event. They found that within 24-48 hours, markers of myelin were significantly reduced in regions associated with motor function and coordination, sensory integration, and emotional regulation. However, two weeks post-event, these markers began to recover, and by two months later, they had re-stabilized.
The study suggests that the brain’s metabolism is acting as a “metabolic safety net,” allowing it to draw fuel from restricted regions when common nutrients are scarce. This finding challenges previous assumptions about the brain’s energy sources and highlights the importance of myelin in maintaining brain function during endurance events.
While the sample size is small, the study aligns with recent research on mice that found myelin can be used as a fat reserve when glucose levels are low. The discovery may have significant implications for our understanding of the brain’s adaptability to stress and its potential role in neurological diseases such as multiple sclerosis.
Source: https://www.sciencealert.com/your-brain-might-start-eating-itself-during-strenuous-endurance-exercise