Posted by: ray porco (rporco@verizon.net) on Tue Jul 5 20:04:29 2005

Hitter,

Sorry if the crap gets a little deep, but there is no other way for me to say it.

The biggest problem with cues is you can’t and shouldn’t use them during competition.
All your senses should be finely attuned to visual reaction. Focus is the watchword.

The point I was trying to make to you /anyone willing to listen with the simple experiment of concentrating on and moving just your left knee, then just your right knee, then just rotating your hips is that:

muscles acting at a joint produce torque and combine this torque with interaction torques (generated by movement of linked joints) to produce the correct amount of torque to accomplish task (anticipatory response). Adjustments are made with inter-segmental interaction torques.

For example, during a reach involving multiple joints, elbow movement will cause an interaction torque to occur at the shoulder, and shoulder movement will cause an interaction torque to occur at the elbow. These torques are velocity and acceleration dependent and will increase in magnitude as movements are made more rapidly.

A Fable:

A centipede was happy, quite,
Until an ant, in fun,
Said "Pray, which leg comes after which?"
Which raised his doubts to such a pitch,
He fell befuddled in the ditch,
Not knowing how to run.

single joint movements are involved in multi-joint tasks but the movements are not controlled separately. If several elemental single-joint commands were executed simultaneously, a normal multi-joint movement would not be generated; instead, a very disorganized movement would arise.

When you wish to get up from your chair to walk across the room, you first think "get up and walk" (a voluntary action) but then you do not think "shift your weight over your right foot, bend your left knee and raise your left foot, extend the left foot in front of you and land on the heel, transfer body weight to the ball of the left foot while raising your right heel and then........"
What you do when you walk, is a learned motor task that has become an involuntary action.