rbibbs
07-24-2004, 01:11 PM
(Subject line borrowed from the movie 'Airplane'.)
Vector is a physics term describing both the direction and amplitude (amount) of a force. In lifting 10# directly above the shoulder, the apparent direction is vertical, and the apparent amplitude is 10#. A lot more is going on within this simple motion example, that illustrates how usable strength is a lot more than the product of muscle tension times cross-sectional area.
Structures humans build, taller than say flagpoles, are cross-braced. We've seen them; bridge towers, cross-country power transmission towers, broadcast towers. All have vertical, horizontal, and diagonal structural members. This is so in order to get the maximum strength into the structure, using the least materials, and enabling the structure to return all the forces it encounters (its own weight, the weight of what it's supporting, plus wind forces) to the ground. As we do, these engineered structures have to resolve all the load vectors they encounter into a nearly-vertical vector that falls within their base (groundfighters will be familiar with this term-- on a tower, it's the 'box' defined by where the tower is bolted to the ground). If the vector falls outside the base, the structure can be in danger of toppling.
In athletic strength pursuits, even in everyday life, we dynamically engineer this same structural strength through cross-bracing within our musculoskeleture. We're under the same constraints as the inanimate structures we used as examples; we want to get the maximum strength using the materials we're given (genetically), and our load vectors have to resolve into nearly-vertical and fall within our base (between our feet if we're standing).
Our job is much more complex though; our example structures are stationary while we're mobile, and their load vectors start out in cardinal planes (vertical and horizontal) whereas we want to be able to generate or counter forces from any vector. Our example of pressing 10# directly over the shoulder generates torsional vectors. That is, in that position, if our musculature 'shut down' and we lost all our cross-bracing, the weight would not fall vertically, we would fall, topple, in an arctuate (rotary) vector toward the side where the weight was suspended. This reveals that the vectors we're generating to cross-brace that apparently-simple load are quite complex.
We'll skip the vectoring that has to take place among wrist/elbow/shoulder/core to raise the weight and balance it once it's there, and just look at supporting it in a straight line. We now have 10# bearing down on our shoulder, displaced from our vertical axis (spine) by 9-12" horizontally, and by 24" (the length of our arm) vertically. First we have to cross-brace this torsional load into a vertical one our spine (primary vertical structural member) can support, through muscles linking arm to shoulder and shoulder to thorax. Since the load is torsional, we then have to cross-brace the thorax to the opposite side of the pelvis. Then, pelvic-girdle muscles have to cross-brace this asymmetry back toward the leg on the side the weight is on. And finally the legs/knees/ankles/feet have to adjust to the asymmetrical load distribution imposed upon them.
It would take pages and pages of complex math to resolve these loads and their cross-braced vectors into the required vertical vector falling within our base, in just this one static position. Yet our neuromuscular system can do it in motion, and in real time. The resolution with which this process operates is what we're training/refining in CST.
Fun, ain't it? :twisted:
Vector is a physics term describing both the direction and amplitude (amount) of a force. In lifting 10# directly above the shoulder, the apparent direction is vertical, and the apparent amplitude is 10#. A lot more is going on within this simple motion example, that illustrates how usable strength is a lot more than the product of muscle tension times cross-sectional area.
Structures humans build, taller than say flagpoles, are cross-braced. We've seen them; bridge towers, cross-country power transmission towers, broadcast towers. All have vertical, horizontal, and diagonal structural members. This is so in order to get the maximum strength into the structure, using the least materials, and enabling the structure to return all the forces it encounters (its own weight, the weight of what it's supporting, plus wind forces) to the ground. As we do, these engineered structures have to resolve all the load vectors they encounter into a nearly-vertical vector that falls within their base (groundfighters will be familiar with this term-- on a tower, it's the 'box' defined by where the tower is bolted to the ground). If the vector falls outside the base, the structure can be in danger of toppling.
In athletic strength pursuits, even in everyday life, we dynamically engineer this same structural strength through cross-bracing within our musculoskeleture. We're under the same constraints as the inanimate structures we used as examples; we want to get the maximum strength using the materials we're given (genetically), and our load vectors have to resolve into nearly-vertical and fall within our base (between our feet if we're standing).
Our job is much more complex though; our example structures are stationary while we're mobile, and their load vectors start out in cardinal planes (vertical and horizontal) whereas we want to be able to generate or counter forces from any vector. Our example of pressing 10# directly over the shoulder generates torsional vectors. That is, in that position, if our musculature 'shut down' and we lost all our cross-bracing, the weight would not fall vertically, we would fall, topple, in an arctuate (rotary) vector toward the side where the weight was suspended. This reveals that the vectors we're generating to cross-brace that apparently-simple load are quite complex.
We'll skip the vectoring that has to take place among wrist/elbow/shoulder/core to raise the weight and balance it once it's there, and just look at supporting it in a straight line. We now have 10# bearing down on our shoulder, displaced from our vertical axis (spine) by 9-12" horizontally, and by 24" (the length of our arm) vertically. First we have to cross-brace this torsional load into a vertical one our spine (primary vertical structural member) can support, through muscles linking arm to shoulder and shoulder to thorax. Since the load is torsional, we then have to cross-brace the thorax to the opposite side of the pelvis. Then, pelvic-girdle muscles have to cross-brace this asymmetry back toward the leg on the side the weight is on. And finally the legs/knees/ankles/feet have to adjust to the asymmetrical load distribution imposed upon them.
It would take pages and pages of complex math to resolve these loads and their cross-braced vectors into the required vertical vector falling within our base, in just this one static position. Yet our neuromuscular system can do it in motion, and in real time. The resolution with which this process operates is what we're training/refining in CST.
Fun, ain't it? :twisted: