026) Rotational Body Movement: Week of February 22, 2009
Aikido involves a lot of rotational body movement. We can create rotations by turning forwards and backwards. Regardless of the direction, there are only two basic types of rotational movement. One, is centrifugal rotation. This type of rotational movement is characterized by movement in which force moves outwards from the center of the rotating object. A good example of this type of movement would be when you swing a rope with a ball attached to it. increased force sends the ball outwards. The second type of rotational movement in called centripetal force. This type of rotational movement is characterized by movement in which force moves towards the center of the rotational object. A good example of this would be water that is flushed down a toilet.
If we are seeking to retain our posture throughout the execution of techniques, then exerting centrifugal force would work against that goal. We would have to utilize body resources towards maintaining our dynamic equilibrium if we are creating a rotational force that moves outwards from our center. When we engage in rotational body movements that are centrifugal in nature, we find that it is not easy to execute a 180 degree turn while maintaining a stable rotational axis. It is very common for Aikidoka to create this type of movement by starting the movement with forceful torque. Although we may be able to exert a significant amount of force towards an opponent, this force still creates a destabilizing force within us.
Centripetal force allows us to rotate around a stable rotational axis. Centripetal force allows us to not have to spend a lot of body energy towards maintaining dynamic equilibrium. Any object that is attached to us, such as the attacker, is forced to move in a centrifugal manner. In other words, we are moving in a manner that significantly unbalances an opponent. This is the optimal type of rotational movement that we can engage in. we move in a stable manner that destabilizes our opponents.
Moving in a centripetal manner requires that we establish a vertical rotational axis in which to move around. The second component is the relaxing of the part of the torso that is furthest away from the rotational axis. This releasing of energy inwards creates a centripetal force towards our center and draws the attacker into our center.
This week we will explore this type of movement in depth. We will begin to see how diffcult it is to “rewire” our bodies to create centripedal movement. Once again, the same realization confronts us. When we are confronted with tension, we are predisposed to react with recipricocal tension. We need to “rewire” our bodies to to react with reciprocal tension, but with a releasing of tension that begins the process of centripedal rotation.
Marc Abrams Sensei