Roundhouse kick (mawashi geri) is the kicking technique that combines forward, upward and sideways directions. In order to produce maximum speed and power and maintain the balance at the same time, both legs have to be engaged in optimal way. That means that support leg can accumulate maximum amount of energy before it transfers it to kicking leg. The accumulation of such energy is possible thanks to grounding action along the leg which takes place from the start up to the passing point. At passing point the energy reaches its maximum level and has to be expressed through the technique. The action of support leg can be tested for example with the help of training partner by pulling your arm on the support leg’ side. Countering such pull unifies leg, torso and arm which is necessary for optimal energy accumulation and transfer to the other side of the body.
The process of energy increase is initiated at the very beginning of the kick and continues until the stage of release (completion). Throughout this time the foot of kicking leg accelerates until reaching the target (or simply completing the kick). It is important that every consecutive stage of the kick shows an increase in acceleration. In order to fully utilize the potential of roundhouse kick both legs have to be equally engaged. At later stage of the kick they form single powerline allowing the energy to stay within the circuit and be applied to the target in precise way (and is not allowed to escape through the unstable tailbone area for example). Importantly, initial action of kicking leg as shown in video (longer distance between the foot and the hip – longer radius) allows better use of centrifugal force which is reduced in cases when kicking leg is raised up prematurely (shorter distance between the foot and the hip – shorter radius).