Scientists Have Figured Out Why Shoelaces Untie Themselves!

     So, your shoelaces weirdly untie themselves while you're running, or walking, and you end up tripping. We've mostly come to accept this as normal, even though it is a bit tiring to have to stop every few meters to retie a pair of especially slippery laces.  Why though, do shoelaces untie themselves so easily? Researchers  at University Of California Berkely - Graduate student Christine Gregg, Christopher Daily-Diamond and their professor Oliver O'Reily teamed together to find out..
They eventually published their findings on April 12 in Proceedings of the Royal Society A.
The trio decided they would try to figure it out by recording Christine Gregg, a co-author of the study, and also a runner on a treadmill while she ran. Capturing the movements of her feet with a  camera that took 900 frames per second.
     They noticed that as Christine ran, her feet hitting the floor of the treadmill struck the ground at about seven times the force of gravity. The knot stretched, then relaxed in response to the force, and as the knot loosened, the swinging leg applied an inertial force on the free ends of her laces which rapidly pulled apart the knots in as little as two strides after.
When looking at two different kinds of knots, the trio realized that one kind of knot was more likely to loosen
They also realized that in comparing two kinds of shoelace knots, one knot was more likely to hold than the other.
The stronger bow is based on a square knot where you cross the left end over the right end,  bring the left end under and out. But wrap the other lace clockwise around it after making a loop in your right wand.
The weaker bow on the other hand is based on a granny knot. To tie this you cross the left end over the right end, bring the left end under and out. Make a loop in your  right hand, wrap the other lace counter-clockwise around the loop, then pull it through.
So , there you have it! Why and How your shoelaces get untied.