Striking and Breaking
One of the four elements of Taekwondo (besides sparring, style forms or Poomse and self-defense) is the break-test. It is usually the right of passage to the next Geup or belt level, and it is an obligatory part of the black-belt exam. It is also a popular element of Taekwondo demonstrations and exhibitions.
Breaking an object is a good way to practice concentration, power, focus, speed and precision on non-living objects, without injuring oneself or another. It is very important to realize that a proper technique is needed and a breaking technique within your limits, because without it you can easily injure yourself, sometimes even permanently!
Practicing the breaking of objects, helps you to realize that your body itself, is a very strong weapon. It also helps you to understand that during practice with a partner, you have to be very careful, exercising respect, control and discipline.
The material that is most often used for breaking techniques is wood since it can be easily broken with either hand or foot. Other materials include bricks, concrete blocks, tiles and sometimes even baseball bats!
Breaking objects can be performed with any rigid part of the body. In Taekwondo, the most common are the hand or the foot, but breaking can also be done by using the elbow, the knee and even the head.
In order to break an object, it is best to start light. Use an object that is easy to break, instead of directly trying to break a thick board, start with a technique and a material in which you feel confident. Use your techniques as they are taught to you and try to be as relaxed as possible. When starting practicing breaking techniques, it might help you to focus a few inches behind the actual point of impact, that way you will achieve a clean break.
- Dry board are more brittle than wet ones and will break more easily.
- If a board does not break, a large force is transmitted back to your body for a relative long time, this could cause pain and injury, so be careful.
- Break boards following the grain. It is much easier!
- When breaking a board, make sure that the persons who holds the board has a firm grip on it. If the board moves during your technique, it will cancel your motion and it will soften your technique. This can also injure you and/or the board holder.
- There are other factors to consider, like angle of strike and size of the target given.
The Physics Behind a Break
Some novice martial arts students, dream of breaking cement blocks with single knife hand strike or a punch, like the world’s greatest martial artists. There are many professional martial arts competitions, where the strongest fighters break boards and concrete using different techniques. The average person wonders how they can make it look so easy. People that aren’t overly large or muscled can still shatter bricks and wood.
The secret to such ability is not in strength. Strength matters to a degree but it is the pure manipulation of strength that determines whether or not you will break that block or if the block will hurt something fierce. The secret behind breaking boards is in technique – speed, impulse, and kinetic energy.
Now without boring you to much, we like to get a little technical, utilizing one of the physics laws of motion, known as the second law of Newton:
FORCE = MASS x ACCELERATION
A body of mass M subject to a force F undergoes an acceleration A that has the same direction as the force and a magnitude that is directly proportional to the force, and inversely proportional to the mass, i.e.,F = ma. Alternatively, the total force applied on a body is equal to the time derivative momentum of the body.
What does all this means on easier to understand terms?, very simple, the shorter your contact is with the board, the bigger the force component will be, so the easier the board will break.
In order to break a board (or any other material), you must cause a shearing moment in the board that is larger than the critical moment or the breaking point for that type of material. When you try to break a board, the board itself is supported on both sides. If you perform your breaking technique well, you will hit the board in the center, which leads to an equal distribution of force on the two parts. Both parts will supply a reverse force of half the initial force.
Imagine that you are hitting a board from a standing position, hitting it in a downward motion. When the force meets the board, the top of the board will be in a state of compression and the bottom will be in tension. This will produce a torque on an axis through the middle of the board, where the strike was applied. If the torque is great enough, the board will break.
Besides force, other elements that are important to consider are power and pressure.
The thicker the board, the harder it is to break it. That is why, often multiple smaller boards instead of one thicker board are used.
Physics is yet again, the power that determines whether or not you can perform a break. By learning ground-breaking techniques, practice and concentration, you should be able to perform your break-test with confidence.
Now, a Little More Physics…but not too much…
We will try to make this easy and not so boring, so bear with us.
What is Impulse?
When we said earlier that something exerts a force – for example, Jackie Chan executing a spinning kick on his opponent, or when a bullet is fired into a wall, there is one very important factor everybody forgets to remember: Time.
If you were in a speeding car, unable to brake, but were given a choice of hitting a haystack or a brick wall, you don’t have to be genius to pick the haystack.
If you had to jump off a cliff to avoid an explosion, would you rather jump off the side leading to jagged rocks or the opposite side leading to a lake down below?
It’s obvious; we don’t even have to think about it. Impulse is the product of force and time.
Impulse = Force x Time
The haystack would increase the time of impact, lessening the force over a longer duration. The water does the same to save us from a devastating fall. Even airbags in cars increase impact times to save your life in a highway collision. In martial arts, the gloves are used to decrease the force dealt by punches that are too dangerous to be done bare-knuckled.
Remember, impulse is always the same in all events. It doesn’t matter what you choose to hit – the impulse is the same. However, the times and forces are different. If the time is long, the force will be mild. If the time is very short, the force is powerful. And when things bounce off an object after hitting them, it is even more deadly in force magnitude.
You have to be precise when you strike a stack of wooden boards with a knife-hand or a punch. Your strength doesn’t nearly matter as much as how you hit the board. Your movement must be fluid and accurate, with no loose movement during the strike. When the blade of your hand, or your fist makes contact, you have to follow through with as much power and speed as you can.
But here’s the trick. Withdraw the knife-hand or punch quickly after following through, ‘bounce’ your hand back off the breaking board like a whip-crack. This is not a weak blow; your strike must be powerful and quick ,but the entire movement must be done without sacrificing technique.
This is easier said than done. It takes much practice to be able to do it right each time. This should be practiced only under a black belted instructor’s supervision, and should never be done at home.
There’s a simple way to explain the secret to breaking boards and cement blocks. Or any life activity in general:
- Decrease the time of impact (to increase the force of impact).
- Follow through with each strike like the way a baseball coach stresses following through with the baseball bat on a swing.
- The impact must be quick and powerful. Keep your striking arm rigid and if you are experienced enough, ‘bounce’ back off the impact, to maximize the destruction. Kinetic energy is the key factor here. Every time you double strength, kinetic energy is doubled. But every time you double speed, kinetic energy isquadrupled, this means four times greater, WOW!
- Use the twisting torque of your shoulders, waist, and the core of your body to amplify the rotational force of the strike. The more you use your entire body in a short duration of time in the martial arts technique; you are capturing the laws of physics in real life.
Impulse = TIME x force (Boxing Gloves)
Impulse = time x FORCE (Bare-knuckles)
Size no longer matters. It is all about using the right technique and making the most of your ‘size.’ You can break boards and concrete blocks easily, if you master the process of using force in motion. It’s not a secret; do not believe advertisements and ‘strength’ pills. This is something you can learn in a high school textbook or in Taekwondo class.
Martial artists must know these laws to master legendary techniques.
To see physics in action, check Sabumnim Hale’s breaking technique, to go there, click on the image bellow.