1. Shaolin Iron Egg
Shaolin monks were once evidently quite concerned that potential opponents might kick them in the groin, so they decided to be prepared.
The idea with people who train “the Iron Egg” are seeking to toughen up potential vulnerable parts of their body, i.e their groin. There is no ancient secret or magic spell that allows Shaolin monks to be able to withstand brutal blows to their groin, they just practice kicking each other in the area so often that they have “toughened” up the region some. In the event they are engaged in hand-to-hand combat with someone, imagine their attacker’s surprise when a low blow has no impact at all.
When kicking each other in the groin ceases to no longer have the impact it once did, a monk may graduate to a more advanced testicle training technique, which involves the attachment of large and heavy objects to the testicles that the monk then drags around. Now if Joe Son had just done some of that training before he met Keith Hackney at UFC 4, things may have gone different for him…