In motocross, the person that holds the racer's water or bike while the racer is preoccupied is called the pit bitch. Although it seems like a derogatory term, the job is actually very important to the racer. Female presence is expected.
In motorcycle racing, every pit bitch graduates to an umbrella girl and the clothing becomes sexier because of the lack of dirt and dust. Also, high heels can be worn on the pavement.
Squid: "Dude I could have totally used a pit bitch after that last moto, I nearly passed the fuck out when I came off the track!"
Pro: "Man, I remember those days. My pit bitch holds my water while I'm in the gate and she even holds my bike when I gotta take a piss!"