T Nation

Science-Heavy Question for CW


#1

Chad and others,
In one of your old Branding Iron columns you mention something to the effect that working an entire chain of muscles is best because the body will work the chain together to avoid strength imbalances. I also remember reading your take on antagonistic supersets and working the antagonists for the same reason; your body will tend to limit the strength of a muscle if it's antagonist across the joint is weak in order to save the joint.

What's the mechanism at work here? Is this mediated by the action of Golgi organs and muscle spindles? Am I way off and there are other proprioreceptors or chemo/hormonal factors at play?

I'm intrigued at what this implies for the benefits of total body training and training what I like to call gross body movements, i.e. large compund total body action vice isolation movements.

Here's that branding iron:
http://www.t-nation.com/readTopic.do?id=459420

(It made me go out and by a 1.5 inch 50 foot manilla rope for truck pulls...)


#2

What will occur is your weakest muscle in the "chain" will fail before the strongest - THAT would cause a strength imbalance.

A muscle is best exercised by direct stimulation.

It's like saying deadlifts are the best way to work traps or lats - we all know your legs will give out before your back does.

I wasn't aware the human body was capable of subconciously mathematically identifying the strength of a muscle compared to the joint AND THEN to manage growth according to the strength of the joint.

Since it isn't so, i'd say this is a false statement.


#3

The body cannot mathematically calculate the force a muscle produces and extrapolate the force acting on the end of the lever it is attached to, no. It can however detect the strectch of the tendons connected to the muscle and the stretch of the muscle fibers, and there are probably other proprioreceptors I'm not aware of.

Here's a link about muscle spindles:
http://www.kcl.ac.uk/teares/gktvc/vc/lt/mspindle/spin1.htm

Zatsiorski, in Strength and Practice of Strength Training about how the Golgi tendon organ will tend to limit maximum force output to protect the joints, muscles and connective tissue, but that elite lifters will "override" that response, as it is generally very conservative. This stems from the fact, If I remember correctly, that elite athletes' muscles are more rigid under tension than the tendons so the tendons deflect more.

Also, while the "weak link" will fail first, I think there is more to it than that. When you perform a maximum clean or snatch the force applied to the bar can exceed the concentric strength of your finger flexors, but , again if I remember correctly, you maintain your grip by way of maximum yielding or eccentric strength. In that case, obviously the forearms are the weakest concentric muscle group but they generally don't impede that particular movement.

I may have mucked all this up, and that's why I wanted a more science savvy person than myself to chime in.


#4

I'd say that it's really a combination of everthing--golgi, spindles, ect. But keep in mind that length, tension, and strength of a muscle comes into play. If you want evidence look at powerlifters--huge upper backs and most of their biceps are pretty good sized too. As a side note, I really never noticed much of an increase in calf size until I started working the hell out of my anterior tibialus.