Why Exercise Changes Your Brain
A scientist who fled fascist Italy and ran a secret lab in her bedroom discovered the first protein that tells nerve cells to grow — laying the groundwork for how we now understand exercise reshaping the brain.
Levi-Montalcini and her collaborator Viktor Hamburger discovered nerve growth factor (NGF) in the late 1940s, the first identified protein shown to be necessary for the growth and survival of specific nerve cells — establishing the entire concept of "growth factors" that has since expanded into a large family of related molecules.
Key Findings
- 1986 Nobel Prize — Levi-Montalcini and Cohen discovered growth factors, including NGF
- NGF was the first protein shown necessary for nerve cell growth and survival
- A related but distinct molecule, BDNF, is what rises with exercise
- NGF and exercise-boosted BDNF are different discoveries, decades apart
The foundational discovery
The 1986 Nobel Prize in Physiology or Medicine was awarded to Rita Levi-Montalcini and Stanley Cohen "for their discoveries of growth factors."1 Levi-Montalcini and Hamburger identified nerve growth factor after observing that a transplanted mouse tumor caused unusual outgrowth of nerve fibers in a chick embryo, concluding the tumor released a nerve-growth-promoting substance.
The molecule people actually mean when they talk about exercise
NGF itself is one specific member of a broader neurotrophin family. A related molecule, brain-derived neurotrophic factor (BDNF), discovered later and separately, is the one most directly linked in subsequent research to exercise — aerobic exercise is consistently shown to raise circulating BDNF levels.2
Why the distinction matters
BDNF is a molecule in the same conceptual family the Nobel Prize established, but a genuinely distinct discovery — not the same protein as NGF. It's worth being precise that "Nobel Prize-winning nerve growth factor" and "exercise boosts BDNF" are related but different findings, decades apart.
The practical takeaway
- Regular aerobic exercise raising BDNF is real, well-supported research building on the growth-factor concept this Nobel Prize established
- NGF and BDNF are related family members, not the same molecule — precision matters when claims cite "Nobel Prize-winning" research
- The underlying concept — the brain responds to specific signaling proteins that promote nerve growth — is the real, awarded contribution
Sources
- "The Nobel Prize in Physiology or Medicine 1986." NobelPrize.org. nobelprize.org
- "Rita Levi-Montalcini biography." Britannica. britannica.com
