[ZenGum]

As well as the teamwork already explained, sometimes they act as a waterboy. In eg the Tour de France, a team rider cruises to the back of the peloton, hooks up with the team car, loads up with drink bottles (I've seen them shoving a dozen inside their shirt) and then powers back up to hook up with the rest of the team and pass on the drinks. Climb the ladder, serve your time, maybe one day YOU will be the number one.