Researchers headed by a team at the University of Pennsylvania have found that exercise does more than strengthen muscles, it also rewires the brain. Studying mice, the investigators discovered that the lasting gain in endurance from repeated exercise—such as the ability to run farther and faster over time—involves changes in brain activity that help muscles and hearts to become stronger. Their results linked the metabolic adaptations that boost endurance to the activity of a group of neurons known as SF1 neurons, in the ventromedial hypothalamus (VMH). “When we lift weights, we think we are just building muscle,” says J. Nicholas Betley, PhD, at the University of Pennsylvania department of biology. “It turns out we might be building up our brain when we exercise.” Betley is corresponding author of the researchers’ published paper in Neuron, titled “Exercise-induced activation of ventromedial hypothalamic steroidogenic factor-1 neurons mediates improvements in endurance.” In their paper the team concluded “By emphasizing the role of the CNS, particularly VMH SF1 neurons, this work suggests that central neural adaptations contribute more significantly to endurance than previously recognized.” “Physical exercise engages adaptive mechanisms that facilitate future exercise performance (colloquially referred to as endurance) and improves physiological function,” the authors wrote. “The benefits from exercise training result from the remodeling of skeletomuscular, cardiovascular, metabolic, and endocrine systems.” And while exercise is associated with remodeling of brain circuits, these adaptations have been presumed to reflect, rather than produce, the endurance benefits that result from repeated exercise. “A lot of people say they feel sharper and their minds…
