In college, we played this drinking game in which we’d bet on which of the fishies in the fishy-screen-saver would cross the screen first. Well, this activity is sort of the same thing for a baby.
You see, your baby doesn’t really know he’s racing you. In order to heat things up, you need to quickly crawl up to him (in the same direction that he is already crawling) and then challenge him to a race by crawling faster and acting excited with noise… much like a person at a stop-light might start gunning their engine if they wanted to challenge you.
If you wanted to put money on the crawling races in my house, I would suggest that the mama always wins on carpet and the baby always wins on hardwood.