Taekkyon kicks are different to those of Taekwondo, Hapkido, and other martial arts. Even though some kicks found in Taekwondo and Hapkido originated from Taekkyon, they do not seem to be performed the same way as there are in Taekkyon.
The stances are different, as are the mechanics of the kicks.
Taekkyon kicks are peformed both when standing very close to the opponent, or like Taekwondo where kicks are usually preformed further away from the opponent.
If a Taekwondo practitioner performas a kick extremely close to an opponent, it will be different to a Taekkyon practitioner performing the same kick. These differences are mostly put down to differences in stance.
Within Taekkyon there are kicks used during a competition, and there are martial kicks to be performed during a fight. The kicks performed during a competition do hurt, but they are not meant to damage the opponent seriously.
Kicks performed during a fight are martial kicks, and thus are designed to result in serious damage.
When the Taekkyon practitioner kicks, internal movement is developed within their body.The whole body moves rather than just moving the kicking leg. Power is derived from bending and rising of the supporting leg at the knee, pushing of the hips, and movement of the upper body in relation to the movement of the kicking leg.
Bending of the supporting leg at the knee, like a spring is integral to Taekkyon kicks. They are smooth & flowing without having a snapping action.
Taekkyon kicks have a pushing action rather than a whipping action seen in Taekwondo.
And knee joints are not locked. When kicking, smoothness, remaining natural, and not being stiff are emphasised.
Please refer to Feet / Stance section to learn more about Taekkyon kicks and how they differ to those of Taekwondo.