This is a really good explanation of the tactics and effort required to win the Track Sprint event. From what I can see, Anna Meares’s winning race is a perfect example of this

http://www.nytimes.com/interactive/2012/08/03/sports/olympics/olympics-cycling-track-sprint-how-to-win.html?smid=fb-share

A Simple Bicycle Race

In the match sprint, riders go around a 250-meter track three times. Typically, they go slowly at the start, until someone makes a move.