Moving your body towards an opponent while you strike is working through depth and uses backup mass to generate power. Rotating the hips or torso while throwing a kick is moving through the width zone and creates power with rotational torque. Dropping your bodyweight downward and settling as you strike is lowering yourself in the height zone employing marriage of gravity.
Let’s take these concepts and see how they apply to a couple basic kicks used across multiple Martial Arts disciplines. At the end of Part 1, I left you with the question, “How can you execute a roundhouse kick and derive power from movement through all three planes of action?” So, let’s start there…
The roundhouse kick can be thrown with either the front or rear leg. In arts such as Tae Kwon Do, Karate and Kenpo it is commonly thrown with either. When used in Kickboxing or Muay Thai, it is more frequently thrown with the back leg, or a version of a switch kick/stance is used to temporarily to place what was the front leg in the rear before execution. No matter the system, the leg, one way or another, moves in a path from left to right or right to left, depending upon which leg is performing the kick. It's apparent that “rotational torque” is a main driver for power creation of a roundhouse kick. The body’s hip and trunk rotate, and the leg becomes an extension of that rotation in a whip-like fashion generating great power at the shin or foot.
When throwing the front foot roundhouse as is common in TKD, Karate, and Kenpo, hip rotation is paramount to generating power. Forward movement of the entire body is rarely of consequence in the front leg roundhouse. This version of the roundhouse is seen less frequently in Muay Thai or Dutch Kickboxing. It’s not that they can’t throw them, but they tend to put more emphasis on power, and it is easier to capitalize on rotational torque when throwing the rear leg roundhouse as the rotational angle is greatly increased.
Now, let’s focus on that rear leg. Interestingly, you can also increase the power of the back leg roundhouse not only via improved rotational torque, but also with marriage of gravity. Think for a moment about the foot upon which you are rotating to bring the back leg forward. When rotating, you elevate the heel and rotate on the ball of the foot. The heel then drops as the strike comes to its apex, thus lowering the body simultaneously at the moment of impact. The result is a timed combination of marriage of gravity and rotational torque. For this reason, you can see another reason why the back leg roundhouse can pack such a wallop.
Another point to consider is how the Dutch Kickboxer frequently throws the roundhouse. Where other systems rely primarily on rotational torque to power up the kick, the Dutch put a large emphasis on back-up mass. I use this term a bit loosely, but please stick with me as I explain. When a Dutch Kickboxer throws a rear leg roundhouse or switch kick roundhouse, they step to a 45-degree angle to the side of the opponent in the direction of which the kicking leg is headed. As a result, the leg doesn’t come around the side of the opponent as it does in many of the other fighting systems. Instead, the shin of the kicking leg “stripes” the front side of their adversary like a seatbelt. This approach uses rotational torque as the body is rotating somewhat, but it also puts to use the idea of back-up mass as a result of the body moving towards the opponent (depth) and “pulling” the leg into the action. Though the mass is not literally “backing-up” the action, the mass is “leading the action” and its movement forward expresses its force through the leg as it pulls it into the opponent. This kicking style can prove very effective in an altercation by combining rotational torque and back-up mass.
FRONT KICK (Ball Kick, Push Kick, Teep)
When considering the front kick, it is important to distinguish between snapping and thrusting. Both the front and rear leg can be used for either. For starters, we will consider the front leg and how it can be used for the front kick.
When using the front leg for a front kick, the knee lifts, and then the leg extends at the knee. The difference between a snapping and thrusting version is in what happens at the hip and when that action occurs. If the kick is to be a snapping style, the hip rotates a bit forward as the foot is approaching the target. The whole torso may additionally move forward as in a TKD skipping front kick or Kenpo drag-up ball kick as the foot approaches the target. No matter the overall motion of the torso, the majority of the movement at the hip happens before contact of the snapping kick. There is, of course, some forward hip motion after contact, but again I said the majority.
In comparison, when considering a thrusting front kick with the front foot, the knee lifts and the lower leg extends similar to the snapping version, but the majority of the hip movement forward happens after the foot makes contact with the opponent. This is because the thrusting front kick is typically used to push the opponent away, whereas the snapping is meant to damage a specific area. Depth of penetration of the weapon is vital to consider and consequently the formation of the foot and which portion is used also varies. But that is a topic for another day.
So, when we consider the front foot front kick, we can see that moving through depth is the primary means of movement to create power. Barring a switch kick which would allow for great rotation of the hip, the main action of the body to generate power with the strike in either version from the front foot is a result of the hips moving forward as rotation is limited.
Now, let’s look at the back leg front kick. Here we will find more ways to create power and, as they are used simultaneously, you will see why the back leg ball kick is much more powerful. The hips can still drive towards target creating power via back-up mass as the back leg comes forward for either a snapping or thrusting front kick. What you also gain in potential force production by using the back leg, though, is the very potent rotational torque. As the back leg comes forward into the kicking action, the kicking hip not only move forward, but it also rotates to a great degree towards the opponent. Whether it be a snapping or thrusting kick, the hips will go through most of their rotation either just before or slightly after impact, respectively.
As mentioned previously in Part 1, the power of the rotation is expressed in the forward projection of the front kick. The circular motion of the hips rotating results in the linear projection of the foot towards an assailant. “Circles become lines and lines become circles.”
Today, we discussed just a couple of kicks. Now would be a good time to think about the other kicks in your arsenal and consider how your body mechanics in each of them is used to derive power. Next week we will finish our discussion of creating power as we look at a few hand strikes. Until next time…