When explaining the biomechanics of movement it’s important to understand how the body functions as a unit with multiple systems within the body working together to execute movement. This is called the kinetic chain and it has three primary systems:

1. Nervous System
2. Muscular System
3. Skeletal System

By inhibiting the nervous system, the kinetic chain is broken and requires more effort to execute a movement. One way of inhibiting the nervous system is by closing your eyes. Sounds simple but makes the movement extremely challenging. I’ll give you a quick example, lift up your foot and execute a 3 count front kick. No close your eyes and try it again. What happened? You noticed that kick became much more difficult, didn’t it? You can use this same application and completely change your training methods. In addition, the kata’s were designed in perfect pattern to where you should end the form exactly where you started. Close your eyes throughout the entire kata and see if you can finish in the same spot. There are three planes of motion that the body can move in:

1. Frontal Plane
2. Sagittal Plane
3. Transverse Plane

Let’s look at the three basic technical kicks and how they fit into these planes of motion to increase the difficulty level. The front kick is executed in the sagittal plane – The most basic kick and easiest to execute. Most movements occur in the sagittal plane, which makes the front kick the easiest to learn. The second kick is the round kick which is executed in the frontal plan. Since this technical kick occurs on the left or right side of the body, it would occur in the frontal plane. Finally, the most difficult of the basic kicks is the sidekick. There is rotation that has to occur within the hip joint to chamber the sidekick, which occurs in the transverse plane.

So how does one train in all planes of motion? In Jhoon Rhee Tae Kwon Do a student must be able to properly execute what we call a 9 count kick. The nine count kick includes the front kick, round kick, sidekick, and hook kick. All the basic kicks must be executed without putting the foot down. Front/Round/Side/Hook Kick.

When training the body there are multiple training variables that can be manipulated to progress or regress a movement. Once a student reaches black belt, it’s important to understand that, yes, there is a more challenging curriculum from 1st to 2nd degree, but it’s also about perfecting the basics. How does one challenge the body? Here a few different training variables that can be used:

1. Range of Motion
2. Speed
3. Frequency
4. Duration
5. Stability
6. Planes of Motion

This article is going to focus on increasing difficulty by understanding the stability principal. The easiest way to explain the stability principal is by using what we call a base of support. When you stand up, both feet are touching the ground which gives you a wide base of support. As soon as a student lifts a leg off the ground they’ve shortened their base which makes it harder to balance. Thus, by decreasing your stability you can make a basic movement more challenging. So how can someone decrease stability while standing on one leg? This is where training tools would come into the picture. Let’s use a dyna-disk for example. Below is a picture of a dyna disk. The dyna-disc allows for movement in all planes of motion in addition to being on an unstable surface. Try doing a front kick on the dyna-disc. What happens? The front kick now becomes extremely difficult.