It started as a bit of a mystery: how did the cooling shirt end up in NASCAR?
Some drivers didn't know. Others assumed it had to be Hendrick Motorsports -- or, more specifically, Jimmie Johnson, who always seemed to be on the cutting edge of fitness and nutrition.
"I was the first driver to wear one," Johnson said, "but the guy who started it was Chad Knaus."
According to Johnson, his crew chief always had an eye on new technology as well as a holistic approach to performance, and that included Johnson.