A true knock out is a level 3 concussion which is the worst one I have only suffered one from backyard football going up in the air and landing backwards with my head whipping into the ground and I tell ya its not fun its 3 or 4 days of throwing up because your balance and the migraine headache is so bad till you throw up, its a bruise on the brain I mean fuck those kinds of shots is what causes CTE and Dave Mirra a BMX superstar just recently blew his head off they think because of CTE but its repeated concussions that are so dangerous especially suffering another before one has had time to heal . Its like a standing 8 count for a boxer more than likely he already has suffered a level 1 concussion but they give him the go light and the bell rings and he keeps going. Blows to the head are not healthy period but they sign up for it and we pay to see it this is a sick world we live in.