The arm triangle, also known as the 'kata gatame,' 'head and arm choke,' or 'side choke,' is a powerful submission used to compress the opponent's carotid arteries, restricting blood flow to the brain. From a dominant position such as side control or mount, isolate one of the opponent's arms across their neck while controlling their head from the same side. Bring the trapped arm upwards into their neck, securing your head tightly against their opposite shoulder. Clasp your hands together, forming a tight grip, and apply pressure by squeezing and driving your head and body weight downwards into their neck. This significantly reduces blood flow to the brain, ultimately forcing a submission. This technique may also be applied in reverse (Reverse arm triangle), in which the set up involves switching your grip so that your own palm rests under your bicep with your choking forearm facing downwards.
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