Roller derby is a full contact sport played on quad roller skates.
Two teams of up to 15 players skate against each other on an elliptical track.
A game consists of two 30 minute halves, broken down into jams which last for no more than 2 minutes.
Teams field up to 5 skaters for each jam, 4 blockers and 1 jammer.
The jammer is the point scorer, aiming to break through the pack for the opportunity to earn ‘lead jammer’, take control of the jam and race around the track to pass opposing players a second time to start scoring points.
Blockers are simultaneously playing offence and defence, aiming to help their jammer get out of the pack and stop the opposing jammer scoring points.
For more details on the rules of roller derby, check out the Women's Flat Track Derby Association website.