The next concept is called Torque. Torque is what causes rotation. Torque is extremely useful in trying to flip an opponent or in applying most joint locks. Torque is sometimes referred to as leverage, and it is the product of the magnitude of the Force and the distance away from the rotational point.

Torque [NM] = Torque equals Force times Distance.

For instance, say you are applying a joint lock on the thumb. Say you press at the near side of the thumb nail, 1 cm from the joint. Then say you instead press at the far end of the thumb nail, 2 cm from the joint. By only moving one centimeter away, you have effectively doubled the Torque on the joint and doubled the pain of your opponent.

The best way to cause rotation is to apply two forces such that they add together and both put Torque around the part of the body you want to rotate. Two forces acting in opposite directions is called a Couple. This is extremely important when trying to trip or sweep an opponent. Try to ‘sweep’ someone by putting your leg behind their leg and pushing on their shoulder, and then try the same thing while sweeping with your leg and pushing on their shoulder at the same time. Also, the farther both forces are from the point about which you are rotating, the larger the Torque. This is why can sometimes be easier to trip tall people, or why you are more stable in grappling when you spread out to a low and wide base.