Are Marathon Winners Determined by their Genetics?

What role does your DNA play in how fast you run? In this Short, Alex Dainis breaks down the real science behind running performance and explores whether marathon winners are shaped more by training or by genetics.

We know that factors like how much you train, the type of training, your altitude, and diet all matter. But researchers have also found genetic differences between marathon runners and non-runners. A 2019 review paper identified 14 genes with small but notable variations—some involved in oxygen response (like the HIF1A gene), others in cell hydration and water balance (like AQP1).

Still, as Alex points out, you can't predict athletic success from genetics alone. It's a complex mix of biological traits and lifestyle factors, and studying these genetic links helps us better understand how all human bodies function—not just those of elite athletes.