An understanding of how these are related and how they function will enable us to learn more rapidly and safely. To understand our power you need to understand the difference between a relaxed and tight muscle. Do this exercise. Have your athlete lie down flat and ask them to be relaxed. Then ask them to tighten up or squeeze a part of their body, then release it. This should teach them the difference between a relaxed body and tense body. If you are not relaxed a physiological process keeps your nerves from telling your muscles how to do a skill, even when they know how to do the skill.
The Four Power Centers
The first power center is your head and neck region. We call this the GPS because it directs your body where you want it to go. To engage or tighten this area, you must make sure your tongue is against the roof of your mouth behind your upper teeth. Try this. Ask your athlete to relax and give a push against their forehead. Then ask them to put their tongue up behind the upper teeth against the roof of the mouth. Then try the test again. They should be much stronger.
The second power center is your thoracic or chest area. This area is engaged by acting as if you were holding your breath making sure your shoulders are in alignment with your ear above the center of your shoulders. Remember your chin should be neutral or level like on a shelf.
The third area is the inner core or the power center for everything. This is engaged by pulling your belly button in and up while squeezing your glutes and hamstrings tightly. This idea can be compared to a spring. The compression of a long spring allows it to be more efficient than that of a short, weak spring in its explosiveness. The body must be long and compressed (squeezed tightly) to produce maximum power.
The fourth power center is the power base. Your triple extension area of hips, knees and ankles. This requires pushing through the toes completely.
If your body is in proper alignment, all of these power centers work together by sending ground forces up through muscles and nerve channels to create power off the ground.