As with other jointlocks, leglocks are more effective with full body leverage. Some attack the large joints of the knee or hip and involve utilizing leverage to counteract the larger muscle groups, while others directly attack ligaments in the knee or the smaller joint of the ankle. Leglocks can involve control positions such as the inside leg triangle or leg knot to maintain control while applying the attack or transitioning between two attacks, though they and some other control positions are banned in Brazilian Jiu-jitsu competition. Some other leglock control positions have been adopted into modern BJJ and submission grappling competitions as "guards" such as the snake guard, one-legged X-guard, and 50/50 Guard, where they are used for both leglocks and to reverse into dominant positions from the bottom.
In training or sparring, leglocks are applied in a slow and controlled manner, and are often not hyperextended such as in the case of the comparatively dangerous heel hook. Instead, submission is signalled before the lock is fully applied. In self-defense application, or when applied improperly or with excessive force, leglocks can cause muscle, tendon and ligament damage, even dislocation or bone fractures.
Some examples of the many types of leglocks are found below.
A kneebar (also known as legbar, kneelock or hiza-juji-gatame) is a leglock that can hyperextend the knee. The basic kneebar technique is similar to that of an armbar. The practitioner will trap the opponent's leg in between their legs and secure the leg with their arms so the opponent's kneecap points towards the body. The practitioner then applies pressure with their hips, forcing the opponent's leg to straighten, hyperextending the knee joint. A variation of the kneebar is similarly accomplished, but instead of holding the leg with the hands, the practitioner will trap the opponent's foot behind one armpit. The practitioner will then apply pressure using their upper body as well and their hips, yielding a greater amount of force applied to the knee, therefore rendering the lock much more difficult to escape before tissue or ligament damage occurs.
An ankle lock (occasionally referred to as a shin lock) is a leglock that is applied to any of the joints in the ankle, typically by hyperextending the talocrural joint through plantar hyperflexion. Ankle locks are often applied in a manner which simultaneously causes a compression lock to the achilles tendon, and sometimes also to the calf muscle.