T Nation

2 Weird Questions


Just wondering about these two things.

If your muscle gets bigger when it is flexed doesn't that mean less mass for the volume so doesn't that make it less dense.
So how come your muscle get's harder when flexed when, if I got this right, it becomes less dense.

And is it possible to work out the small muscles like the ones in your jaw, and like the ones in your hands and fingers. Like strap weights to your jaw, and get like freaky pulging jaw muscles or ripped hands?

I know these are wierd questions but I was kind of wondering.


Bottom line, you muscle does not get bigger when it flexes. Your muscle contracts, making it less flat and therefore it sticks out more.

It is possible to work out any voluntary muscle, which does include the ones in your jaw. Personally I don't see the point, but hey, if it floats your boat.

There isn't much in the way of muscle in your hands, that's mostly tendons and ligaments attached to muscles in your forearms.

Check www.exrx.net for further details of anatomy and exercises.


Okay, here is my shot at answering your questions, take it for what it is worth, I am no expert but here is my best common sense guess:

Let's think about your bicep. It runs pretty much from your elbow up to your shoulder. Relaxed (stretched) it is longer and flatter. Contracted (bunched) it is shortened, but raises higher. Basically, the mass or density doesn't change, just where the fibers are located.

Now if you think about a 'pumped' muscle, it is full of blood. So yes, it is denser, more weight in the same volume.

For your second question, I think if you were to try to build these muscles, injuries would come before visable results. These muscles are not designed for strength, they are designed for repetitive motion, such as chewing, or typing. I doubt the fiber type has the capability for much growth.


On the "jaw and finger" issue, that is what gives support to the idea that your body grows as a whole. The muscles in my jaw are more prominant than they were when I was much smaller. It isn't like I was chewing weights over the years.

In fact, MOST bodybuilders have larger facial muscles the bigger they get. Dexter Jackson is one whose face has changed drastically from when he first started competing. It gets wider along with his neck.

As far as whether you "train" them directly for growth, I agree that you would probably either see fatigue or injury issues before you actually just built up your jaw muscles alone. It sounds like a TMD waiting to happen.


It's all those burgers you were eating, Prof., they took a lot of munching.


this conclusion is something i've made myself.. however to me it seems, though other muscles may grow without being directly worked, they don't seem to get much in the way of stronger until they are worked intentionally.... may just be in my situation.

About eh fingers and hands. Using the captains of cursh grippers to a high level has shown me that the two biggest places for increas in size are the thumb pad and the muscle that contracts the pinky in running along the 'edge' of your hand as if karate chopping someone i guess. Also vascularity and pumped up look on the back of the hand between thumb and index finger are also good aspects of hand training. Thick vascular muscled up 'tight' looking hands are a quite aesthetic in bodybuilding terms.


About the jaw and hand muscles. The jaw is the densest volentary muscle in in your body theirfore the hardest to grow, the calves run second.