Every Tae Kwon Do student has been told by, his or her instructor, to "relax"
Every Tae Kwon Do student has heard about the importance of sine wave.
Senior black belts will tell you that power is generated with very little effort.
Here are some things you can try that will help you understand why and how. They will give you a feeling of why it works without bothering with the proper scientific names for what is going on. You need to complete all the exercises for the best result.
Exercise #1 (only do this with adult supervision)
Find a car to push. One with a manual transmission is best. Have someone steer that can control the vehicle and apply the brake if necessary. Here is what you will find out. You have to push very hard to get the car moving. Once it starts rolling, it is very easy to keep it going. Your body is just like the car and the down up down of sine wave is designed to provide the first big push.
Exercise #2 (pair up with a partner for this one)
One-student steps into right walking stance with obverse middle punch. Then have the student lock out the front leg. The partner places his hands on the punch and braces to see what happens next. Once everyone is ready, the student in walking stance bends the front leg to form a proper walking stance. The partner will fill a push. It is that push which provides the force to get your body moving (remember the car?). What the student in walking stance has done is to complete the down part of sine wave that is included in down up down. Ask the student that was in walking stance, if he had to exert any effort to cause the force. Switch roles and do it again.
Exercise #3 (stay with a partner)
One student will form a walking stance while the other watches. Straighten the front leg and then bend it into the correct position. Note what happens. What happens is the body moves forward and the top of the head drops. We will talk about this after the next exercise.
Exercise #4 (be careful with this one)
Find something heavy. Put it on a table then push it off. It hits the floor with a crash. Keep your toes from under it because it could do enough damage to send you to the hospital. Wait a minute . . . Hmmm, a heavy weight moving toward the floor can do damage. . . . a student (whose head gets lower as he forms a walking stance) causes a force on his partners hands. . . . And the student doesn't have to exert effort. . . . What is going on is gravity and it is possible to generate tremendous force by simply relaxing. Now you know why every Tae Kwon Do instructor you will ever meet says relax and use sine wave. "Down up down" it can generate tremendous power with out any effort.
Exercise #5 (Isn't there a better way to do it? Can't it be muscled?)
Get out the mats - take turns standing on the mat and see what the fastest way to get down is. See if any one has any ideas- and try them. You will find that the fastest way down is to fall. So relaxing is the fastest way to get power into your Tae Kwon Do walking stance, or any stance for that matter.
Exercise #6 (you will need a heavy bag for this one.)
Make sure the area is clear, because this one can take you for a ride. Wind up the bag like kids do with swings on a playground. Notice the bag gets higher when you do this. Get somebody young and enthusiastic ready to grab the bag to stop the spin. Give it a spin to get it going - when it is spinning well - give the volunteer the command to "grab it". Observe the effect. Wow - rotation has energy.
Exercise #7 (two partners working with L stance)Part 1
One partner assumes a right L stance while the other observes. Extend an obverse punch to the center of the stance and cover it with the other hand. Have the student straighten, and lock out the right leg. Then have the student relax the right leg back into the proper L stance position - you should see the extended fists move through an arc. (This is a great opportunity to correct a students L stance). If you do not see the fists move through an arc, then look at the legs, the student is not "dropping" into the stance and is simply squatting with both legs. Squatting provides no rotational power. The front leg should act as a pivot and flex slightly but the body must rotate as the rear leg is flexed.Part 2
When everyone has the rotation down, proceed to this part. One student executes obverse punch in right L stance. He then keeps the punch out and locks out his right leg. The partner places his hands on the obverse punch. The student then relaxes his right leg so he drops into right L stance. The observer will feel a force on his hand --- a force that the student generated by relaxing.
Exercise #8 (get in a group and talk about what you have seen)
What these experiments show is that by using sine wave, and relaxing, you can generate force and power for free, without any effort on your part. Tae Kwon Do, especially patterns, is full of examples where we use gravity and our body weight to generate force in a focused direction. That is where the power of Tae Kwon Do comes from - we are using our body weight and gravity in a coordinated, timed motion, to generate the maximum possible amount of power with the least effort. Remember the exercise on the mat? The best way to do that is by relaxing.
Exercise #9 (more rotation)
Get a single board and support it in a holder or on some cinder blocks. Now extend your hand above it, and using only the rotation of your hand, break the board. It can be done, usually only by senior black belts, and it demonstrates rotational power. It also explains why we time the rotation of the arms in a block until the last possible moment. That way the attacking tool has the highest speed possible. Rotating your hands through the entire time that your arms are moving does not generate the amount of power created by waiting until the last possible moment. Talk about this and let everyone try to break the board. But understand this - the power of this rotation is enough to break one board - don't waste it with sloppy technique. Remember the power in a proper stance and don't waste that with improper sine wave. All of things taken together are what make Tae Kwon Do the RELAXED POWER HOUSE that it is.Mr. Ed Tardoni