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What Happens When a Fighter is Knocked Out in Combat Sports?

When people tune in for any combat sport, they mainly want to see one thing and one thing alone — knockouts. Whether it’s boxing, mixed martial arts or kickboxing, nothing gets the crowd going more than a crazy knockout victory.

While they’re great to witness and will always be a memorable moment, what actually happens to the fighters who get knocked out?

When a fighter gets knocked out by a blunt force to the head area, their brain shuts itself down immediately, which is why fighters often go unconscious. This is the brain’s automatic response to reset the body.

What happens to their bodies and what are the long-term effects? In this article, we will look at everything related to what happens when a fighter gets knocked out in combat sports.

What happens to your body when you get knocked out?

It should be noted that there are two types of knockouts. One is a technical knockout(TKO) which is when a fighter is not properly defending themselves which results in the referee stepping in and stopping the contest.

The other is the more well-known knockout(KO) in which a fighter goes out cold or doesn’t know where they are.

What causes the latter to happen? Essentially, your body has taken enough blunt trauma and your brain shuts itself down which is why fighters sometimes go unconscious. This is the brain’s effort to reset the body.

If a strike causes the brain to move around in the cranium(skull), this can also result in a knockout and more specifically, a concussion where the fighter doesn’t have their wits about them. In some cases, the short-term as well as long-term effects could be fatal after a knockout.

Another reason why fighters go out cold is due to their blood and oxygen flow following a fight-ending strike. The sinus regulates this flow of blood and oxygen, but when a good strike connects, it can jolt the sinus. This results in the flow of both blood and oxygen altering rapidly which can cause a blackout.

Why does the fighter’s body stiffen up after being knocked out?

When fighters go stiff, this is known as the body’s fencing response. This is when a fighter has absorbed such a strong impact that it causes a concussion and the result is an extension of the arms as they’re falling down mid-air. This response usually lasts a few seconds until the fighter’s brain and body come to its senses and the fighter proceeds to wake up.

What happens to the brain during knockout?

When the brain moves around in the cranium due to the force of a strike or punch, the fighter is dealing with a traumatic brain injury. What this does essentially forces the brain to reset by causing a loss of consciousness. A vast number of neurotransmitters will fire simultaneously which causes an overload in the nervous system. The end result is temporary paralysis, which is why fighters who get knocked out tend to stay that way usually for a couple of seconds to up to a minute. 

How long can someone be knocked out by a punch?

How long a person can be knocked out for depends on the individual and the severity of the strike they suffered that caused the knockout.

In combat sports, it’s very common to see fighters wake up in a matter of seconds. However, in some cases, it can be minutes and if it’s longer than that, it is uncommon and a cause for concern. Some fighters have never woken up as a result of serious brain injuries which have eventually led to their deaths.

Why does a jaw punch knock someone out?

It’s not necessary that a punch to the jaw will guarantee that someone will get knocked out. Any punch, no matter where it is on the head, can cause a knockout if it causes the recipient’s brain to slam inside the skull.

Punches to the jaw, however, are more likely to cause a knockout because of the rotation generated compared to a punch on the dome or forehead.

Do knockouts cause brain damage?

Knockouts do cause brain damage, but it depends on the severity of the knockout. Any knockout in combat sports will result in the dying of brain cells and brain tissue. In most cases, these brain cells regenerate and form new ones.

However, the more severe a strike, the more brain cells and tissue is damaged which could result in no regeneration of these lost parts. Essentially, the more cells die, the more brain tissue you lose. When that happens, it can lead to symptoms like memory problems, a change in mood, confusion, information being processed much slower and inevitably brain damage or chronic traumatic encephalopathy (CTE).

Do MMA Fighters Get Brain Damage?

Do fighters get a concussion every time they get knocked out?

If a fighter is knocked out cold, goes unconscious or blacks out, they have suffered a concussion. This is because all those results happen whenever the brain has suffered a traumatic injury or has been rattled inside the skull causing the body to reset and the fighter to go out cold. To keep it simple, you can be concussed without getting knocked out. But you will be concussed every time you are knocked out.

What does being knocked out feel like?

Being knocked out is similar to being asleep. In many cases, when a fighter is awoken from a knockout, they will feel better and refreshed until the pain of the strike eventually starts to affect them.

In other cases, fighters have a headache right after getting woken up. It’s also very common for fighters to have no recollection or memory of what happened right after the knockout. In the UFC, many fighters have remarked how they had no memory of giving an interview or meeting someone right after they were woken up from a knockout.

How can you wake someone up if they’ve been knocked out?

You can’t specifically wake up someone who has been knocked out. In combat sports, you usually see a fighter wake up when a referee or team member attends to them. However, this is not due to any external signal or action — it’s because the brain and body has recovered and reset from the trauma it experienced from the knockout blow.

Do UFC fighters get CT scans?

UFC fighters do get CT scans if they have been on the receiving end of a knockout. However, UFC fighters do not get CT scans prior to their fights. One big reason for this is that continuous CT scans would expose them to high levels of radiation. 

Which is more brutal: boxing or MMA?

While there can be more devastating knockouts in MMA, boxing is the more brutal sport, especially when brain damage is considered. One simple reason is that most times a fighter is knocked down or appears to be concussed in MMA, the fight is usually ended by the referee or the opponent who lands quick follow-up strikes.

In boxing, there is a 10-second count, and if the fighter is able to convince the referee they can keep fighting, they will continue to fight and potentially absorb more damage.

10 counts in boxing
Photo by Biser Todorov

There’s also the fact that there is more padding on the gloves in boxing and since the head is the main target other than the body, boxers absorb more damage to the head in the long-term compared to MMA fighters. For example, a fight in MMA can end in a submission without the loser receiving a single strike to the head. All of this contributes to the reason why there are so many more deaths from boxing due to brain damage even in recent years compared to MMA.

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While knockouts are great to watch, they can have short and long-term effects that affect the fighter on the receiving end. After reading this article, you should hopefully be more than aware of what happens during and after a knockout along with the after-effects on a fighter’s brain.