Overview
- Teams led by the University of Castilla-La Mancha report cardiorespiratory capacity nearly triple what is typical for his age.
- Measurements disclosed by researchers include about 77% muscle mass, cardiac output near 18 liters per minute, and strong mitochondrial function.
- Juan López began running at 66 and went on to win the 2024 European marathon title in the M80 category.
- He set the 50 km world record in 2025, reinforcing lab findings with elite age-group performance.
- López credits genetics, daily training, and a simple diet, and he stays fit to care for his dependent wife as international media track ongoing studies.