There is no physiological limit preventing humans from running for more than 5 hours, and marathon runners aiming for a time of 4:30 or longer are completely legitimate.

noli's read

The assertion that humans are not built for prolonged exertion contradicts the endurance running hypothesis, which is widely supported in evolutionary anthropology (e.g., the work of Bramble & Lieberman, observational studies). Research confirms that our species possesses specific morphological adaptations—such as elastic Achilles tendons and efficient thermoregulation through sweating—that allow for long-distance running. It is true that beyond 5 hours, metabolic challenges (managing glycogen stores, hydration) increase, but this is a matter of physical preparation rather than biological impossibility. The creator rightly nuances elitist discourse by reminding us that performance is relative and accessible with proper training. There is no exaggeration here; the message aligns with sports science consensus regarding the accessibility of endurance.

the sources

No named source held this one up — that absence is part of the verdict.