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It’s good to keep on your toes. Metaphorically¹, that is. Not when you’re actually out for a stroll. Because a new study suggests that it takes nearly twice as much energy to walk on your toes than it does to land on your heel.

Humans are among a small handful of animals that tend to strut² heel-to-toe. Chimps³ and other apes do it, as do bears. But most critters bounce on the balls of their feet—think cats and dogs—while others trot⁴ on their toes, like horses and deer.

To find out whether our gait gives us any advantages, scientists asked 27 volunteers to walk on a treadmill⁵ all three ways: heel-first, ball-of-the-foot first, or up on tippy toes. The participants also wore face masks that enabled the researchers to measure their oxygen consumption. The results: the subjects walking on the balls of their feet, in addition to looking ridiculous, expended⁶ 50 percent more energy. The ones prancing⁷ on their toes needed 83 percent more energy. The study is in the Journal of Experimental Biology.

The bottom line: landing on our heels provides more leverage⁸ and limits energy losses to the ground. And does not look like a tribute to classic Monty Python.