Can a Glass Jaw be conditioned into an Iron Chin in Boxing and MMA?

The fact of not being able to take a punch in contact sports is embarrassing yet the biggest reality in the world of Boxing and MMA. People often use the term “glass jaw” when it comes to describing a person with a weak chin.

You must have seen this term thrown around with one fighter taunting the other in regard to their inability to eat punches.

One of the most prominent examples is that of the McGregor vs Khabib pre-match conference in 2018. (Refer to the clip below).

But Conor though unsuccessful isn’t the only one to give this reference, many boxers and MMA fighters look down upon their opponent who often gets knocked out.

If you’ve been at the receiving end of a sizzling punch in the fight, you absolutely know what that moment feels like.

If you haven’t, then let me describe it to you – it feels like time stands still and everything is frozen – you’re basically shaken from the impact.

Though your face freezes upon impact, it affects translate to your entire body. Within a second of getting hit, either of the two things will happen:

  1. Your legs will crumble and you’ll move like you have rubber legs
  2. Your body will rattle and you’ll fall flat on the canvas, not in a state to realize that the opponent followed that strike with two-three extra punches.

The inability to take punches in disheartening for any fighter and can force them to rethink their career. 

Though the subject has always been a mystery, there’s much more to knockout than just the inability of the chin to eat a punch. 

Let’s understand the relationship of the knockout with fight sport in general.

If you’ve been at the receiving end of a sizzling punch in the fight, you absolutely know what that moment feels like.

If you haven’t, then let me describe it to you – it feels like time stands still and everything is frozen – you’re basically shaken from the impact.

Though your face freezes upon impact, it affects translate to your entire body. Within a second of getting hit, either of the two things will happen:

  1. Your legs will crumble and you’ll move like you have rubber legs
  2. Your body will rattle and you’ll fall flat on the canvas, not in a state to realize that the opponent followed that strike with two-three extra punches.

Let me share an example with you from recent history. Amir Khan, one of the most talented boxers with no shortage of skills was out boxing his opponent Danny Garcia and was expecting to win the match.

However, he got caught with the left hook and fell flat onto the mat. (This is what fight fans refer to as Glass Jaw). Glass Jaw is not a one-off accident but rather a tendency to crumble time and time again.

Moving forward with yet another boxing example. This time it’s Gennady Golovkin. A man who’s known to have an iron jaw.

Not only is GGG a world-class counterpuncher but his ability to eat up punches is simply masterclass. 


In arguably, Golovkin chin has been his biggest strength. And his iron chin demoralizes his opponents to a great extent as he rarely blinks upon the impact. (This is what fight fans refer to as an Iron Chin).

What’s an Iron Chin? 

It’s basically an ability of a fighter to eat up devastating punches without being teleported to a parallel universe. Just a hyperbole. But you get my point.

Another prominent boxing example is Mike Tyson, who was such an aggressive fighter that he trained his chin so to be able to eat up punches. There’s a reason why they call him Iron Mike. We’ll discuss his drills later in this blog, so keep reading.

On the other hand, there’s an uber-talented boxer in Amir Khan who even after having an advantage lost the matches because he wasn’t able to eat up punches and take punishment to his chin.

The science behind knockout in boxing and MMA

Scientifically, a knockout happens when your brain slams inside of your skull upon the impact. To put it straight, the more your head moves after the blow, the more prone it is to knockout or concussion. 

Now, that we know what causes the concussion, we sure can work towards working it to improve. But before we move towards that, let’s understand the concept in a deeper sense.

Clearing the misconceptions about the role of the chin in a knockout​

Most of the fighters and athletes in different martial arts carry a major misconception about the chin. In reality, the ability to eat a punch has got nothing to do with your chin or the way your jawline is structured.

Your head rests on your neck. Assume your head is a lever and your neck is a fulcrum. Your brain is the object placed at the end of the liver than depends upon the lever for movement.

Now understand this, the wider and bigger the fulcrum is the less it can move. Thus, when your neck is bigger and strong, your head will move considerably less upon impact which will prevent the knockout substantially.

Has this got anything to do with genetics? Absolutely? Can it be conditioned to improve the strength? Absolutely.

How can you condition your chin to be able to take punches? ​

Firstly, you need to condition your neck and enhance the toughness to decrease the susceptibility to knockouts.

To train your chin, you actually need to train your head movement and strengthen your neck and not your jaw or any muscles related to it.

You might be wondering, why do fighters attack the chin then? Well, the reason is that chin is a lovely place to land a blow because it’s the target which leads to the most rotational acceleration in your brain stem.

Basically, a target where you can send your opponents on a trip without a passport.

So, how can they counter it? They can do so by mitigating the rotational acceleration. And the best way to do so is to develop neck straight which makes your neck capable of absorbing the force upon impact.

Why don’t athletes condition their chin in this manner? ​

Maybe most of them sleep on this idea or haven’t yet figured about the science behind it. The majority of the fighters are generally focused on working their neck for primary movement – back to front, front to back.

Surprisingly, very few boxers and MMA fighters work on the rotational neck strength. You can absolutely work your neck to develop anti-rotation strength which can prevent your head from spinning and your brain from dancing in your head.

Techniques such as a three-dimensional approach include rotational neck training which can improve your conditioning against a defining blow. Which brings us to the penultimate question.

Can you develop an Iron Chin? ​

I would say, it depends upon how badly you want to achieve it. You can simply push limits with your teammates during sparring sessions.

Face up against guys with extreme punching power and weight. Learn to get accustomed to their punches.

Do specific exercises capable of improving your neck and the muscles around your jaw. One fine conditioning exercise in the olden times was chewing tree barks to strengthen jaw muscles.

You can improve significantly by enhancing your neck toughness. Below is the list of exercises that can help you condition your neck.

I won’t claim that you will have an iron chin after these drills, but you’ll be well-conditioned to eat punches on your chin as compared to the current times.

Exercises to strengthen your neck and overcome a glass jaw

Weighted Neck Raise

When performing these exercises, make sure you’re taking care of the movement. As visible in this video below. Simple put a cloth between the weight (5-25lbs) and bite down on the towel which will work your jaw. Once you bite it, simply move face up and down and that will activate the muscles in your neck. 

Yes, No, Idk Movement ​

No, not the Kane and Daniel Bryan one. It’s a simple chin tuck movement related to the yes movement. Herein, our aim to learn to control our head movement.

With your chin tucked in, try to move your chin in either direction saying No with a head gesture.

Do it in full range of motion and try to bring your chin as close to your shoulders as you can. After 10 reps, try to do the forward movement as if you were saying Yes and then proceed to maybe. 

Maybe Movement ​

What’s not a Yes or a No? It’s maybe. To do the maybe movement. Keep your chin tucked and move it towards either shoulder. This exercise requires you to move your head in a tilting motion. It’s similar to the No movement except, you’re not exercising the full range of motion.

Chin Tuck ​

Chin Tuck is a great exercise and is recommended to every individual. From a neutral position, you try to bring your chin inwards and move it towards your neck. It’s a widely used exercise to improve chin strength.

Howling at the Moon ​

A simple exercise, you do what it says. You look up to the ceiling and howl. Not with the sound obviously. This exercise is going to work your jaw and the neck. It will strengthen your jaw, platysma and sternomastoid. As soon as you do this, you’ll feel your neck muscles working.

Neck Bridges

Like Shane Fazen explains in this video below, “Your neck supports your head which supports the brain. Your brain is like a Jell-O, inner fluid encased within your hard skull.” If you listen closely, he explains it in a simple manner.

What causes concussion is the fact that upon getting hit, your brain stays in the same spot, where your head moves instantaneously upon the impact.

Similar instances can be understood with a car accident example. Coming back onto the topic, let’s check out some more exercises which you can any time to condition your neck better.

Inarguably one of Mike Tyson’s favorite drills to condition his jaw and improve his neck strength. To perform a neck bridge, simply lay down on your back and lift up on to the back of your head. Bridge up with your hips off the ground.

Now when doing this, be extremely careful with the execution. Keep the movement slow and smooth and do not rush or you’ll injure your neck.

In this drill, you’re placing a great amount of weight on your neck and so you wouldn’t want it to snap. So, just take it slow

Cervical Flexion​

The next advanced exercise is Cervical Flexion. It involves keeping your jaw closed. Your tongue on the roof of your mouth. And try to flatten the back of your neck. Try to make your neck flush against the wall. And you’ll instantly feel the tension on the front of your neck and on your nose.

Prone Cobra ​

An advanced neck exercise strengthens the muscles of your neck, upper back, and shoulder girdle. You should do this exercise while lying on the floor with your face down. Herein, the goal is to use gravity as the resistance in order to strengthen your neck and back.

To perform a prone cobra, place your forehead on a rolled-up towel for comfort. Place your arms towards the side and palms on the floor.

While placing the tongue on the roof of your mouth, pinch the shoulder blades together and make an attempt to lift your hands off the floor.

When doing this drill, roll your elbows in, with your palms out and thumbs pointing upwards.

Gently lift your forehead off the towel whilst keeping eyes straight at the floor level. Hold the position for 10 seconds each.

Neck Isometrics ​

You can perform neck isometrics using a hand or by pressing your head against the wall or soft wall. Place your palm against the forehead while sitting straight.

You can use both your arms for increased resistance. With your palm against your forehead, now push your head down intending to bring your chin closer to your chest.

When you try to do this, you’ll feel resistance from your hands.

When you feel it, move your hands to the back of the head and push back and try to look towards the ceiling.

You can also do this exercise sideways by bringing your neck towards the right ear or your left ear.

Remember to hold each position for a period of up to 3 or 5 seconds and do 10 sets each. While performing isometric exercises, do not allow your head to move.

Using Exercise Band and Extension ​

Many entrepreneurs have capitalized on the growing market of neck exercises and have blessed us with some exceptional products.

You can use these bands and extensions to work your neck against different levels of resistance. You can use the band, to do angular left and right head movement.

You can use it for front and back movement. You can also do exercises while sitting and perform the up and down movement.

Products such as NeckFlex are advisable for such exercises, you can watch Shane’s review on this product.

Can an iron chin get worn down upon repeated impact?

Absolutely, there are many fighters who as they progress witness the condition of their chin deteriorating. It’s common. Upon reaching a certain age, a human brain and our jaw are not able to recover and return back to its pristine position.

MMA fighters such as Overeem, Liddell, and Wanderlei Silva fell prey to the Broken Jaw Theory and after brutal knockouts or all-out wars in the Octagon saw their career arcs dip. Similar can be said for boxers such as Amir Khan, James Toney and Klitschko.

Conclusion ​

Yes, genetics do have a lot of say. But not completely. You can work on things and improve them significantly. Getting punched in the face is pretty common in the fighting sport. 

A reality which you have to come to terms with. Your best bet would be to find out ways and work the aspects that pull you down rather than simply accepting your genetics as fate.