June '20

High temperatures and the sunlight that falls on our dark shoes in the summer are an infernal combination. Your feet and other body parts heat up. There is nothing left but to respond with droplets of water, also known as sweat, which decrease the body’s temperature as they evaporate from the surface.

The cooling system, which has been being developed over millions of years, did not anticipate the anthropologically red-hot new invention of footwear, which limits airflow and impedes effective evaporation. The resulting warm and moist microclimate (one could call it “tropical”) confuses the lower extremities about why the water is not evaporating. “Rainforest, humid air, slow evaporation,” they diagnose. “Ha! More sweat!” they conclude with good intentions, triggering a vicious cycle.

Our savior can only be a sock. Miniature holes in the sock’s fiber are able to absorb water and hold it at a safe distance from the panicking tootsie. But how should the sock pump moisture out, when water is naturally pulled downward by gravity? The only way out is up! Our woven heroine brandishes an unexpected ace: capillary action. If the rungs of her metaphorical ladder are set up correctly, the conspiring oxygen-hydrogen sock-climbers can inch their way out of the shoe. They then blend in with the first whiff of fresh air.

To tie it up nicely, your new sock is made from extremely airy bamboo fiber. That fast-growing plant originates in humid tropical areas and is widely used to produce ladders or even high-rise scaffolding.