Arq. Bras. Cardiol. 2025; 122(5): e20250231

Beyond Limits: What 366 Consecutive Marathons Reveal about the Human Heart

Fabricio Braga, Ricardo Stein

DOI: 10.36660/abc.20250231i

This Short Editorial is referred by the Research article "Record-Breaking Endurance of 366 Marathons in 366 Days: A Case Study".

Western culture has always celebrated the pursuit of physical extremes — from ancient epics to modern ultramarathons, endurance has always been more than sport: it is narrative, identity, and defiance of perceived limits. Completing a single marathon already places substantial stress on the cardiovascular, metabolic, and musculoskeletal systems. Doing a Marathon 366 times over 366 consecutive days shifts the focus from physiology to philosophy: Just how far can the human heart truly go?

The case study published in this issue of Arquivos Brasileiros de Cardiologia documents a feat previously unimaginable: a Brazilian amateur athlete completed a full marathon every single day for a year — all under systematic medical supervision. More than a Guinness World Record, this is a real-time exploration of human adaptability. The athlete’s cardiovascular system remained remarkably stable throughout the year, with maximal oxygen uptake (VO₂ max), cardiac structure, and biomarkers within physiological ranges, despite the extreme exercise volume.

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