The Physics of Judo
Judo is a martial art that is centered around physics. Even just the concept of throwing somebody is physics. To practice judo and not have a basic knowledge of physics is insane considering that physics is what makes judo possible. Judo is sport that consist of throws, take downs and over all control. Judo without physics is like have a sandwich with just bread, you don’t get much out of it. To understand how physics comes into play with judo we must start with Newton’s laws of motion.
“Newton’s first law: law of inertia, a net or unbalanced force is needed to change the state of motion of and object. In a judo match, two players try to throw each other by first off-balancing the other player, the fitting their body into a position underneath their opponent for a throw, and finally throwing their opponent squarely on their back. The key to throwing the other player in the off-balance. Without first off-balancing your opponent, your chance of successfully completing a throw are slim. You’re also asking to be countered if you don’t off-balance first.”(1)
“The first law of motion is important if you want to successfully throw your opponent in a match. For instance, suppose your opponent makes a move to his right in order to make you move to you left. In the instance that you are moving, you’re temporarily off-balanced. Rather than letting your opponent keep control of the situation you and take advantage of his motion by using Newton’s first law. In this scenario, the statement “an object in motion will stay in motion” applies. As he is in motion you quickly turn into your opponent enabling you to lift him up with your hips and throw him.”(1)
“Newton’s second law: F=ma, the acceleration of a body is proportional to the net force on it and inversely proportion al to its mass. If you are in a match, facing an opponent who weighs less than you and you push him with a quick acceleration of the hand, you will have exerted a larger force on him then you would have if you had only pushed him with a smaller acceleration and chances are that he will move or fall easier for you. If, on the other hand, your opponent has more mass than you, the acceleration that you hit the smaller man with will have less force on the more massive man because acceleration is inversely proportional to his mass.
The faster you throw your opponent with, the larger the force that he falls with will hit the mat. If he is larger than you, then he will not need to exert as much acceleration on you in order to achieve the same amount of force a man smaller that yo would. So, what does this tell you? That you’d be better off...