I don't know for a fact what the origin was but I suspect it was simply a preventive measure b/c of the padded suits the racers have to wear and sit in at high heat to wait for the start of the race. Simple necessity I'd guess.
Dragging knee is for the track, and dragging tail is for the lot. --Kane Friesen
When you're in a car, you're watching a movie; when you're on a bike, you're in the movie. --Robert Pirsig
Identity theft is not Fun