Muscle toning

[ged]

I was looking though my anatomy/physiology textbook the other day, and i found this entry on muscle toning. ill copy some of it in.

"In any skeletal muscle, some motor units are always active, even when the entire muscle is not contracting. Their contractions do not produce enough tension to cause movement, but they do tense and firm the muscle. This resting tension in a skeletal muscle is called muscle tone. A muscle with little muscle tone appears limp and flaccid, whereas one with moderate muscle tone is firm and solid. The identity of the stimulated motor units changes constantly, so a constant tension in the attached tendon is maintained, but individual muscle fibers can relax.

Resting muscle tone stabilizes the position of bones and joints. For example, in muscles involved with balance and posture, enough motor units are stimulated to produce the tension needed to maintain body position. Muscle tone also helps prevent sudden, unctrolled changes in the position of bones and joints."

There's more, but i'll leave it at that.

Anyway, i've always believed that 'muscle tone', ie definition, was just low bodyfat percentage - made sense to me because i don't think i've seen anyone with high bodyfat and 'toned' muscle.

I'm not 100% sure, but I think people have posted on here citing studies that have disproved toning. If this is correct, it results in me being confused.

btw, the textbook is 'Fundamentals of Anatomy and Physiology" by Martini, Fifth Edition 2001.

[Serpent]

The fact that you haven't seen muscle tone in people without low body fat is simply because they don't have low body fat, therefore you can't see the muscles anyway due to the fat.

I don't think I could have said that less clearly if I tried! ;)

In essence, low body fat will highlight toned muscles. However, not having low body fat does not mean that the muscles aren't toned.

All this is by the definition of muscle tone as in the book you quoted. A "toned" appearance, by modern aesthetic standards, is both muscle tone AND low body fat.

That's my understanding. IronFist? SevenStar?

[SevenStar]

That's my understanding also.

[GunnedDownAtrocity]

mine too. even though i dont count.

[inic]

think of sammo hung maybe?

[ElPietro]

Muscle is muscle. There are different fibre types, and you can affect the composition within the muscle cells, but overall the tissue will look the same externally. You can only grow or shrink the muscle fibres. The rest is a result of fat and water weight.

You can increase the number of mitochondria within a muscle which would make the cell structure more apt for oxidative fuel based activity, but I highly doubt that this would make the fibre type itself look "toned" or "untoned".

And of course certain motor units would be active at virtually all times. Think of spinal erectors supporting the spinal column which allow us to remain upright, or muscles along the neck that keep our heads up, muscles that control movement in the eye also are probably always active, even in sleep, as I believe eye movement still occurs.

Tone is such a bad word to use in physiology, it can be applied accurately, only when speaking in aesthetic terms. Hopefully, new versions of text will try to eliminate the use of this word.