Why We Walk on Our Heels Instead of Our Toes
Walking heel-to-toe gives humans the mechanical advantage of longer "virtual limbs," suggests UA researcher James Webber.
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It was an especially interesting question from Webber's perspective, because those who do barefoot running, or "natural running," land on the middle or balls of their feet instead of the heels when they run — a stride that would feel unnatural when walking.
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As Webber explains: "Humans land on their heel and push off on their toes. You land at one point, and then you push off from another point eight to 10 inches away from where you started. If you connect those points to make a pivot point, it happens underneath the ground, basically, and you end up with a new kind of limb length that you can understand. Mechanically, it's like we have a much longer leg than you would expect."
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They found that toe-first walkers moved slower and had to work 10 percent harder than those walking with a conventional stride, and that conventional walkers' limbs were, in essence, 15 centimeters longer than toe-first walkers.
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It's no wonder humans are so set in our ways when it comes to walking heel-first — we've been doing it for a long time. Scientists know from footprints found preserved in volcanic ash in Latoli, Tanzania, that ancient hominins practiced heel-to-toe walking as early as 3.6 million years ago.