Study Explains Why Shoes Come Untied

Are loose shoestrings tying you up in knots? Don't let them. Turns out there's a scientific reason why shoestrings come untied.

A new study by mechanical engineers at the University of California in Berkeley illustrates why. Whipping forces act like an invisible hand, loosening the knot and then tugging on the free ends of your laces until the whole thing unravels.

"We deal with them coming untied all the time," said Colin Adams, a mathematician at Williams College in Williamstown, Mass., who was not involved with the study. "And yet, nobody's ever taken the time to say: Why does it happen?"

Now we have a better idea why. One more thing: The "square knot" holds up better than the "granny knot."

And if you need a hand, there's a TED Talk video on how to tie your shoes.https://hls.ted.com/talks/1150.m3u8