Think you know how to lace your shoes? Mathematician Burkard Polster of Monash University in Australia suggests you think again. He has found that the traditional crisscross and straight lacing methods we all learned as children are far less efficient than an obscure hybrid lacing pattern.
Considering each string-eyelet combination as a pulley, Polster analyzed all the reasonable lacings, those in which every one helps pull the two sides of the shoe together. For a shoe having seven pairs of eyelets, there are about 400 million options. Traditional crisscross and straight lacings were the strongest alternatives. But when it comes to efficiency, these two use far more lace than an elaborate series of horizontal, vertical, and crisscross lacing that Polster calls a "bow tie" method.
Should we all change our shoe fastening techniques? "You could save a lot of lace," Polster says.