10/2/12

Why Muscles Seem to Twitch More When at Rest

Find out why your muscles begin twitching while at rest, but stop when you move.


One day I sat at my computer and began noticing that my leg muscles were twitching all over. Not much sooner, I had completed a two hour power hike and trail run, during which I perceived no twitching.

If I moved my knees in and out, or repeatedly went up and down on the balls of my feet, the twitching ceased. Or did it?

I’ve had twitching (fasciculations), but never while I was moving that muscle group. Or so it seemed.

For this article I consulted with Anthony P. Geraci, MD, Founder and Director of neurOasis Neurology, Clinical Assistant Professor of Neurology, NYU School of Medicine. 

Dr. Geraci explains, “Benign twitches are more prominent when the muscle is at rest for two major reasons.  First, if we are at rest—sitting or lying down—we are more likely to notice a twitch.

“Second, even when we think we are perfectly still, our nerves and muscles are very busy keeping us still.  We have a feedback loop between the muscles and spine that keeps our posture steady, etc.  Our agonist and antagonist muscles are always in a state of balance. 

“For example, when we move our biceps, the triceps receives signals from the spine to inhibit it from contracting and fighting against the bicep.  This phenomenon occurs constantly and the inhibitory signals keep the muscle membranes stable.”

So if you’re at your computer in a seemingly immobile state, your muscle fibers aren’t exactly inert. There’s still activity going on. 

Think of them as being on standby for more prominent movement such as shifting position in your chair. And of course, it makes a lot of sense that you wouldn’t feel twitching while you’re walking, cleaning the house or exercising.

The fact that muscles “seem” to twitch only while at rest in NO way points to a possible disease process. There is nothing intrinsic about rest that suggests a pathology. 

Where do you have twitching?

No comments:

Post a Comment