Use of the triangle is rather extensive in martial arts, particularly as a way of conceptualizing stability and control (but also in such things as footwork); specifically such concepts as “three points of control“.
The triangle lends stability to structure. The structure of a choke or joint lock is enhanced by means of a triangle principle.
Here we see, in the rear naked choke, (1) one point of control is your arm cutting off blood in the carotid artery of the opponent’s neck, (2) one point of control is your hand on the opponent’s head and (3) another one is your hand from the arm wrapped around his neck on your own arm that’s controlling his head (if you are performing the choke). This kind of control can be applied to a variety of locks on the arm, leg, and ankle. Let’s look at famous UFC MMA fighter Bas Rutten performing the rear naked choke.
In this next choke, literally called The Triangle Choke, you use your legs to perform the choke; with your opponent’s neck between your legs, you wrap one leg around his neck and place the back of the knee on your own foot of the leg that’s wrap around his neck, and apply pressure to choke him out. Again, let’s watch Bas Rutten perform the choke.
The Figure 4 is a joint lock that can put pressure on the shoulder joint, the elbow, or wrist depending on how it is performed and in what position. It involves three points of control; (1)your hand grabbing his wrist, (2) the other arm wrapped around his arm, and (3) the hand on the arm wrapped around his grabbing your own wrist or arm. The lock creates a great amount of leverage and makes it easy to apply pressure to the opponent’s joint and can even be used to throw him. Let’s let Bas Rutten demonstrate once more.
The Achilles Lock creates excruciating pain for the person it’s used on by applying heavy pressure to the Achilles Tendon. It is done similarly to the Figure 4, by wrapping one arm under the leg, at the Achilles Tendon, putting your free hand on your opponent’s leg and grabbing the arm of that hand with the hand of the arm wrapped under your opponent’s leg. This clip of Ryron Gracie demonstrating a foothold is basically the same position and procedure as the Achilles Lock; you will have to feel out with a partner when you get the right spot to apply pressure to the Achilles tendon.
In addition, the triangle principle can be used when grappling with the Eskrima Stick. In this next video we see the conceptualization of the defender’s own shoulders and his stick as the base of a triangle and the pressure he applies toward the opponent as the top point of her triangle. As he penetrates her depth zone and keeps the pressure on her depth zone, he chooses the correct angle to apply a throw using a triangular lock; he uses his stick on her chest, his hand on her wrist, and his hand holding his stick all as points of control.
So, as you can see, in the correct position, and pressuring the right areas, with the stability and control of a three-point lock or choke, you will have the leverage to easily apply pressure to submit or even disable or throw an opponent.