If they are air filled, it is due to an air leak that can happen during strenuous fighting. The solution is to lance the swollen air and let it escape. Some people will also give antibiotics in case of secondary infections.
The important thing is to keep it deflated until the air leak heals. A small jagged cut is more effective than puncturing with a needle. A needle puncture tends to seal back off before the air leak is healed.
Good luck.
