Roller Derby is a full contact sport, played mainly by women on rollerskates, by rollerskates we mean the proper ones with wheels at four corners.
Each bout is made up of two half an hour periods, these periods consist of ‘jams’ which can last up to two minutes.
A jam starts with four blockers and one jammer from each team on the track. On the first whistle the blockers set off around the track, they form ‘the pack’. On the second whistle the jammers race to catch up with and break through the pack, it is the job of the blockers to stop the opposing jammer from getting through. A jammer scores a point for her team for each opposing player she passes and at the end the team with the most points wins!