Weight classes exist for one reason: size is an advantage. In MMA, where strikes, takedowns and submissions compound that advantage, divisions are the sport's basic fairness mechanism.

How divisions work

• Fighters weigh in the day before an event and must be at or under their division's limit.
• Major promotions run divisions from strawweight up to heavyweight, each with its own champion.
• Missing weight usually costs the fighter part of their purse and can cancel title stakes.

The trade-off

Cutting weight can bring a size edge on fight night, but a hard cut drains exactly the attributes — chin, cardio, power — a fighter needs most. The scale is the first opponent every fighter faces.