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If your arms were long enough, would it be physically possible to skip with them? © Getty Images

If your arms were long enough, would it be physically possible to skip with them?

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Asked by: Sara Stevenson, Maidstone

No. And you can prove this for yourself with a simple experiment. Hold your hands behind your back and try lifting them above your head. You won’t get very far because the shape of your shoulder joints means that each arm must tilt outwards from your body as it rotates back up over your head. Holding your arms close together stops this rotation from happening, and longer arms won’t help with this.

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A skipping rope gets around this problem by connecting your hands with a flexible line that is free to rotate through half a turn and then back again. The skipping rope is effectively extending the length of your fingers, rather than your arms, but even with very long fingers you would need to hold hands very loosely to allow them to rotate past each other.

Some very flexible people can approximate a sort of arm skipping, but it’s actually more of a rowing motion since each arm rises over their head alternately, to allow the arms to rotate one at a time.

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luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.

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