Biomechanics Question

[Robert schmitt]

I should have explained the effect of the golgi better. You are right they do inhibit muscle contration. But from this inhibitory effect they spread the force of contraction equally over all muscle fibers. Each gogi tendon organ is only inervated by 10-15 muscle fibers connected in series. so each tendon organ is detecting tension in portins of the muscle not the entire muscle. If a load becomes so great through out the entire muscle yes the entire muscle would shut down. However, you should not be reaching this point in a controled wieght training enviroment. So when looking at a typical training enviroment. The effect would be to theoretically envolve more of the muscle fibers and re-enforcing contractile patterns that involve more of the muscle in a uniform matter which is what you were asking. My first respone was very poorly stated I'm sorry.

From Guyton & Hall "Textbook of Nuerophysiology" 9th ed. p 692 Unit XI

"Another function of the Golgi tendon relfex is to equalize the contractile forces of the seperate Musscle fibers. That is, those fibers that exert excess tension become inhibited by the reflex, whereas those that exert too little tension become more excited because of the absence of reflex inhibition. This would spread the muscle load over all the fibers and especilly would precevnt damage to isolated areas of a muscle where small numbers of fibers might be over loaded."

[Robert schmitt]

The other thing is I'm not sure what you mean by torque. the def of torqu is: ( I high lighted what I think you mean by torque with in the def.)

In physics, torque can informally be thought of as "rotational force" or "angular force" which causes a change in rotational motion. This force is defined by linear force multiplied by a radius. The SI units for Torque are newton metres. In the U.S., foot-pounds force (ft·lbf) are also commonly encountered. The symbol for torque is τ, the Greek letter tau. The concept of torque, also called moment or couple, originated with the work of Archimedes on levers. The rotational analogues of force, mass, and acceleration are torque, moment of inertia, and angular acceleration respectively. The force applied to a lever, multiplied by its distance from the lever's fulcrum, is the torque. For example, a force of three newtons applied two metres from the fulcrum exerts the same torque as one newton applied six metres from the fulcrum. This assumes the force is in a direction at right angles to the straight lever.

Mathematically, the torque on a particle (which has the position r in some reference frame) can be defined as the cross product:


where

r is the particle's position vector
x is the symbol for vector cross product
F is the force acting on the particle,
or, more generally, torque can be defined as the rate of change of angular momentum,


where L is the angular momentum vector, and t stands for time. As a consequence of either of these definitions, torque is a vector, which points along the axis of the rotation it would tend to cause.