Go for the knees! This commonly is performed straight out of an opponent’s guard. Once the guard is broken, the fighter on top steps through the guard (turning his or her back to the opponent), and grabs a leg. Then, using leverage, the performer falls back with the leg in both hands and secures it like an arm bar by pulling the toes in (the performer must also wrap their legs around the isolated leg to add leverage).
A kneebar (technically known as a straight legbar) is a leglock which hyperextends the knee. The basic kneebar is performed similarly to an armbar by holding the opponents leg in between the legs and arms so the opponent’s kneecap points towards the body. By pushing the hips forward, the opponent’s leg is straightened, and further leveraging hyperextends the knee. A variation of the kneebar is done similarly, but instead of holding the leg with the hands, the opponent’s foot is pushed behind one armpit. By pushing the shoulder backwards and pushing the hips forward, a greater amount of force is applied to the knee, and the lock becomes much more difficult to escape.