Summary: We often credit muscles, lungs, and heart for fitness gains, but a new study co-led by UT Southwestern researchers shows the brain plays a central role: specific neurons in the ventromedial hypothalamus (VMH) program and sustain improvements in physical endurance.
The team identified a population of VMH neurons defined by the protein steroidogenic factor-1 (SF1) that responds to exercise, retains a trace of past activity, and actively drives the body’s long-term endurance adaptations. Rather than merely reflecting peripheral changes, these neurons appear to coordinate the physiological remodeling that underlies improved stamina.
Key Facts
- SF1 “memory”: During treadmill training in mice, SF1-producing neurons in the VMH showed progressively increased activity, creating a neural trace of prior exercise that correlated with later endurance gains.
- Direct control of stamina: Silencing these neurons prevented endurance improvements from training, while boosting their activity enabled mice to break through typical fitness plateaus.
- Brain as a mediator: The results shift part of the focus from muscle- and heart-centered explanations toward the brain as a key intermediary that tells the body how to adapt.
- Metabolic consequences: Earlier work found that without SF1 neurons, mice did not reap exercise-linked metabolic benefits such as increased calorie burning or resistance to weight gain.
- Therapeutic potential: Understanding how these neurons encode exercise history could lead to interventions that mimic exercise’s benefits for people with limited mobility.
Source: UT Southwestern
Neurons in the ventromedial hypothalamus (VMH) appear to direct the body to boost endurance in response to exercise, according to a study co-led by UT Southwestern Medical Center researchers.
Published in Neuron, the study explains how the brain’s response to activity is essential for the physiological remodeling that produces lasting improvements in performance and metabolism. These findings could eventually inform treatments that reproduce exercise benefits when physical movement is limited.
“People usually think of exercise adaptations as changes in muscles, the heart, or lungs. Our work demonstrates that the brain itself can program endurance capacity,” said Kevin Williams, Ph.D., Associate Professor of Internal Medicine, member of the Center for Hypothalamic Research, and an investigator in the Peter O’Donnell Jr. Brain Institute at UT Southwestern. Dr. Williams co-led the study with J. Nicholas Betley, Ph.D., Associate Professor of Biology at the University of Pennsylvania, and Erik B. Bloss, Ph.D., Assistant Professor at The Jackson Laboratory.
Previous research has shown that exercise alters the brain—promoting neurogenesis, strengthening neural connections, and reducing inflammation—but those changes were typically viewed as consequences of physical training. This study turns that view around by showing hypothalamic neurons actively drive the body’s adaptive response.
Earlier work from UT Southwestern and others pointed to SF1, a protein made by a subset of VMH neurons, as important for exercise-related metabolic benefits. Mice lacking SF1 signaling failed to develop normal muscle adaptations, resist weight gain, or increase calorie burning after increased activity. To investigate further, the researchers trained mice on a strict treadmill program—running five days a week with a progressively faster long run each week.
The trained mice showed clear endurance gains that peaked around three weeks. During training, SF1-producing neurons increased their activity, and repeated exercise made that post-exercise activation progressively larger—creating what the team describes as a neural memory of prior activity. Blocking those neurons after training prevented further endurance improvements, while stimulating them promoted continued gains beyond the usual plateau.
These observations indicate that VMH SF1 neurons encode exercise history through changes in excitability and synaptic inputs and that this hypothalamic plasticity is necessary for coordinating the systemic adaptations that support greater endurance. The researchers plan to investigate how these neurons detect prior exercise and how downstream circuits contribute to the observed effects.
Long-term, this line of research could enable therapies that activate the same brain circuits to produce some benefits of training for people who cannot exercise due to illness, injury, or limited mobility.
“Traditionally we think of improved athletic performance as the product of building the musculoskeletal, cardiovascular, and respiratory systems,” said Dr. Betley. “Our findings place the brain squarely in the middle of that process, acting as a controller that drives peripheral systems to upgrade.”
Other UT Southwestern contributors to the study include Joel K. Elmquist, D.V.M., Ph.D.; Teppei Fujikawa, Ph.D.; Eunsang Hwang, Ph.D.; and Kyle Grose, B.S., among others.
Funding: This research was supported by grants from the University of Pennsylvania School of Arts and Sciences; the National Institutes of Health; the National Science Foundation; the National Research Foundation of Korea; Rhode Island biomedical research awards and foundations; Providence College; and the University of Pennsylvania.
Key Questions Answered:
A: In a sense, yes. The study shows that signals in the VMH translate the intent and experience of exercise into physiological commands that promote endurance. The brain acts like a coach, integrating exercise history and instructing peripheral tissues to adapt.
A: That is a long-term goal. If researchers can safely and precisely target the SF1 neurons or their downstream pathways, it may be possible to recreate some exercise benefits for individuals who cannot perform physical training.
A: Fitness plateaus often reflect an equilibrium between current demands and the body’s programmed set point. The study found that enhancing activity in SF1 neurons can push past that ceiling, implying the brain helps set those limits and can be manipulated to extend gains.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- The journal paper was reviewed in full.
- Additional context was added by staff.
About this exercise and neuroscience research news
Author: Kevin Williams
Source: UT Southwestern
Contact: Kevin Williams – UT Southwestern
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Exercise-induced activation of ventromedial hypothalamic steroidogenic factor-1 neurons mediates improvements in endurance” by Morgan Kindel et al., Neuron.
DOI:10.1016/j.neuron.2025.12.033
Abstract
Exercise-induced activation of ventromedial hypothalamic steroidogenic factor-1 neurons mediates improvements in endurance
Repeated exercise provides robust physiological benefits by remodeling skeletal muscle, cardiovascular, metabolic, and endocrine systems. In mice, activation of central nervous system circuits after exercise is essential for subsequent improvements in endurance and metabolism. Ventromedial hypothalamic SF1 neurons become active after exercise, and repeated training amplifies this post-exercise activation.
Training increases the intrinsic excitability of SF1 neurons and the density of their excitatory synapses, suggesting exercise history is encoded through hypothalamic plasticity. Blocking SF1 neuron output prevents the endurance and metabolic gains normally gained from exercise training, while stimulating these neurons after exercise enhances endurance improvements. These results demonstrate that exercise-induced SF1 neuron activity in the hypothalamus is required to coordinate the physiological adaptations that follow repeated training.