London, Dec. 4 (Reuters): An Australian mathematician has solved a problem that has confronted generations of youngsters and stumped a few adults — lacing shoes.
Most people use the criss-cross or the straight lace technique but Burkard Polster, of the Monash University in Victoria, Australia, has shown that although they are the strongest, neither is the most efficient method.
“We demonstrate mathematically that the shortest lacing is neither of these, but instead is a rarely used and unexpected type of lacing known as bowtie lacing,” Polster said in research reported in the science journal Nature.
The bowtie technique, in which the laces go across from one eyelet to another, down to the next one and then criss-cross in a repeating pattern, uses all of the shoe’s eyelets but the least amount of lace.
“When you think about it, learning to lace and tie shoes is a major hurdle that we all had to overcome while growing up,” Polster said in an interview.
He incorporated friction, eyelet alignment and the material of the laces in his equation, but he doesn’t expect his findings to change the way people lace their shoes. “For me it was a fun, quirky problem to think about for a while,” he said.
Polster’s preferred method is the criss-cross, although he does admit to sometimes straight lacing one shoe and criss-crossing on the other.
But he has no doubt about the best knot to use. Although people prefer the granny knot, the square, or reef knot, is better and tests have shown that it is unlikely to come undone.
If knots, lacing techniques and mathematical formulas are just too complicated, there is always Velcro. “I think it is conceivable that now there might be a few kids who will never master these tasks,” Polster added.