Roller derby is one of the fastest growing sports in the world — here's how it works

This is roller derby, one of the fastest growing sports in the world.

It is a game that pits two teams of 14 players against each other, skating anti-clockwise around an oval track. Each team has 5 players on track at a time, 4 blockers and 1 jammer.

Jammers are identified by the stars on their helmets and they score points by trying to overlap opposing players. It is up to the blockers to negate this by stopping opposing jammers passing them, preventing points being scored.

The sport is predominately played by all-female squads, but also has a growing number of male, unisex and junior teams; showing how much the sport is expanding.

Produced by David Ibekwe. Special thanks to Lianna Brinded, Seaside Siren Roller Girls, and Essex Men's Roller Derby.

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