Toughest Part Of Sport: Hard route to knowledge for sport climber Mark Chan

In a room dedicated to upward mobility, the aerospace engineering student contemplates his ascent. He looks up at the wall in Boulder World and figures out the geometry of his climbing route. He's so lean he seems built of cords, wires and elastic, yet he's a cousin of weightlifters. For like them, he starts work by dipping his hands into powdered chalk.

Mark Chan's chalk is kept in a bag and his hands emerge coated in a film of white dust. Chalk helps his grip and his life depends on his grip. Sometimes his 57kg frame hangs from a tiny hold which is a few millimetres wide and he can't afford to fall. He won't die, just lose.