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The Science of Shoelacing?

Australian mathematician Burkard Polster has been all tied up in an unusual research project. This month, he announced in Nature magazine that he has found the most efficient way to lace a shoe. It turns out this method has been kicked to the curb. It's rarely used!

Polster spent years comparing hundreds of "reasonable" ways to lace a shoe. He says that bowtie lacing, which uses both Xs and vertical lacings (see photo), takes up the least amount of shoelace.

Most folks opt for either criss-crossing (also below) or straight lacing to tie their shoes. Though a bit wasteful, these two ways give the tightest fit. It's a result of "hundreds of years of trial and error," says Polster. What's next? An in-depth look at belt-buckling?

Next: Tigers Hold Their Ground