Next to finger, toes, ears and nose, an athlete’s lungs suffer most from the temperatures we’ve enjoyed this week. Minuscule ice crystals inhaled in our raw air can cut into the airway and bronchi, resulting in chronic cough and infections. Cross country skiers are particularly susceptible to the effects and many develop asthma from the stress their sport puts on the respiratory system.

That’s why Northwest Territories biathlete Brendan Green used a heat exchanger all week.

He held the whistle-sized plastic device in his mouth and, as he exhaled, the air passed thin aluminum coils that trapped the warmth and condensed the moisture expelled with his breath. When Green breathed in, he drew the -30 degree outside air through the chamber where it was warmed and humidified before entering his lungs.

But why would Green want to run around with a plastic bit in his mouth? He only has to remove it for a blast of the Yukon’s razor-sharp atmosphere, to feel the benefit. Green keeps his exchanger in while racing. Occasionally, ice builds up over the opening and can sometimes be constricting, but he flicks it off and keeps going.

“I started skiing in Hay River when I was about three or four and I’ve been serious about biathlon for about six years,” said the 20-year-old who’s training with the National Junior team in Canmore, Alberta, “but I wish I’d had this when I trained at home.”

Green’s first look at a heat exchanger came during competition at the 2005 World Junior Championships in Finland. Scandinavians have been using exchangers for a decade. “I’d only ever seen the Europeans with these, and then in one of the Quebec coaches brought them for us,” Green said. He tried it once and was sold. At $50 each, it’s a small price to pay for internal frost protection.

The device has gained interest at the Athletes’ Village. “Some of the other athletes have asked me about it,” said Green, “and the long-track speed skating coaches.” Spectators and athletes can see the device in action when Green races in the cross country skiing events during Week Two at Mt. McIntyre.