well, Berardi says there isn't really what I'm thinking about. Let's say you've got 100 neurons connected to the muscle fibers in your biceps (I know it's unrealistical, but just to put a number on things) when you work your biceps, these will be activated to recruit the muscle fibers they connect to. However, at rest, these neurons still send some action potentials. Could this be something like "resting motor unit tone"?
I get that more contractile proteins will lead to a harder look because of higher muscle density (muscle tension is different than density, tension is created, as I see it, by muscle fibers contracting or trying to contract, you can get more muscle density without getting more muscle tension), but that is different from what I mean by "resting muscle tone"
What I mean is different from what myogenic tone, since what I'm talking about is simply nerve activation at rest, not necessarily related to how many contractile proteins you've got.
Examples: (assuming training can improve what I mean by resting muscle tone)
Example 1 Increased resting muscle tension due to more nerve activation
At rest 2 of the 100 MUs in the biceps are active.
Now after training for a while 4 of the MUs in the biceps will be active at rest.
In what I mean by resting muscle tone, more contractile proteins wouldn't increase it.
Example 2 increase in resting muscle tension due to more contractile proteins:
the 2 motor units that are active at rest are connected to muscle fibers that together contain 100000 contractile proteins, now after training, this number increases to 100500. The 2 motor units that are active during rest are now causing 500 more contractile proteins to constantly cross-bridge at rest. This would mean more muscle tension.
But that's different from what I said in the first example.
I think this is also different from myogenic tone, since myogenic tone appears to just be like this:
100000 contractile proteins - training - 100500 proteins = bigger and firmer muscles, but not necissarily because of more neural activity or because more proteins are cross-bridges?
More contractile elements in the muscle lead to more neuro-stimulation leads to greater myogenic tone (contraction at rest).
How does more contractile elements in the muscle lead to more neuro-stimulation? I get that, as in my second example, more contractile proteins would mean more contractile proteins crossbridging at rest if the same level of MU fireing was maintained at rest, but how could more proteins lead to MORE neuro stimulation (which I guess would have to be higher frequency of MU discharge or more MUs active at rest)
One of my textbooks says this about neural tone, though in a different area than with muscles: (McArdle, et al, 2006)
Most organs receive sympathetic and parasympathetic stimulation. Both systems maintain a constant degree of activation (neural tone)
This is what I'm refering too, although not with sympathetic and parasympathetic stimulation, but a constant degree of motor unit stimulation at rest which helps with for example maintaining posture, etc.
has this to say about the word "tone"
12. Physiology. a. the normal state of tension or responsiveness of the organs or tissues of the body.
So more tension in the muscles would mean an increased tone. I guess you could say something like "active tone" (same as neurological tone) which would be how tense a muscle is when it is working.
then resting tone, which is how tense a muscle is at rest. Contributed to by a few motor neurons constantly fireing to keep some tension in the muscle. The amount of tension in the muscle could be increased without increasing the amount of neurons constantly fireing (example 2) or with increasing the amount of neurons constantly fireing (example 1)
catch my drift? I hope the post is understandable.. I think I've found some different tone "things" Do you agree that these would be different from each other, and that they actually do exist? If so, then the problem is just the terminology, what is named what..
McArdle William D, Katch Frank I, & Katch Victor L (2006)
Essentials of Exercise Physiology 3d ed. Lippincott Williams & Wilkins