Why Do Shoelaces Always Unfasten? Scientists Find Answers

Most kids learn how to tie their shoelaces by the time they reach kindergarten. However, no matter how old they get, these laces always seem to end up getting untied. This problem is not something only children struggle with. Even adults have a hard time keeping their shoelaces tied in a perfect knot the entire day with no re-tying.

There is a scientific explanation for that. According to a new study by mechanical engineers at UC Berkeley, the forces endured from stomping and whipping act like an invisible hand to them. These forces then start loosening the knot and tugging on the ends of the laces, until eventually the strings unfasten.

With the help of a slow-motion camera, the study was able to show that such unraveling happens in a matter of seconds, triggered by a complex reaction of the said forces. While this experiment may be simple enough, there are other bigger implications to the explanation, as far as science is concerned.

Christopher Daily-Diamond, co-author of the study and a graduate student at Berkeley, said that once the science of the shoelaces are understood, it is easier to apply it to various aspects of science. Among these, he noted, included understanding DNA or microstructures that are also known to fail under dynamic forces.

BBC News also noted that the group conducted tests with the help of different varieties of laces. While some are better than others as far as knot-tying is concerned, they all suffer from the same cause. Study co-author Christine Gregg noted that what makes this especially interesting is the fact that the mechanism allows laces to stay firmly knotted for a long time. Nonetheless, one motion that can cause the loosening can start an avalanche effect, eventually leading to what they call a "knot failure."