Oh i have Zero Cardio, but being 6'5 and about 230 means I usually just KO folks immediately. But the bad cardio catches up with me when i have to run more than a mile after the fight ( Cops etc). Strangely Ive never hurt my knuckles, elbows are definitely good Close up though! But Yeah i Never train holding my hands high, i only train punch power. Good point about my (bad) footwork though!