Polynesians, no just Hawaiians, have an exceptionnaly robust constitution due to natural selection. They are extremely well represented in combat sports and rugby.
They also have a culture of street fight and brawls.
I watched a documentary from the french legion sleection a while ago, and the applicants have to do combat test, basically figthing another applicant in a ring. The instructors were saying that polynesians were exceptionnaly gifted for combat, with a unique mix of strength, chin and toughness.