Why do laces loosen?
Interest in why lace knots loosen is not just an academic issue. Scientists point out that this research may help create better surgeon knots and stronger fibers, and even solve the mystery of why deep-sea optical cables become tangled and broken. It can also help computer animators improve their imitation of hair movement, because the movement and distortion of hair are similar to the movement of shoelaces and knots.
The researchers found that when walking, the combined impact and acceleration of a shoelace totaled up to seven gravitational accelerations, which was about the same as the gravitational acceleration that Apollo spacecraft endured when it returned to the Earth's atmosphere.
Further experiments show that simply stamping up and down is not enough to loosen the end of the shoelace, or just swing back and forth. Only when two forces interlace can the lace knot be loosened - the lace is pulled continuously with the change of direction of force, and this repeated impact eventually leads to the lace knot loosening.
For this, we recommand the No Tie Shoelaces to you, so that you don't have to worry about the shoelace would loosen when you running or you may tripped by untied shoelaces.