Never mind the eye twitching; learn why computer use can cause your leg muscles to twitch like mad!

“When muscle twitching becomes chronic or frequent, that’s when you begin to consider an underlying cause,” points out Carolyn Dean, MD, ND – Medical Advisory Board Member, Nutritional Magnesium Association at

Don’t panic at the term “underlying cause.” The underlying cause can be quite benign.

“The most common one is magnesium deficiency,” says Dr. Dean. “Magnesium is responsible for muscle relaxation, and when you don’t have enough, then its sister-mineral, calcium, causes muscle contraction.”

A muscle twitch or fasciculation is actually a contraction—but on a much smaller scale than the contraction involved in crossing your legs, let alone running up a flight of stairs.

“Too much calcium and not enough magnesium can cause ongoing twitching,” says Dr. Dean.

“Magnesium citrate powder mixed with hot or cold water is a highly absorbable form that can be mixed into a water bottle and can be sipped throughout the day.”

So why do leg muscles seem to twitch more when you sit before the computer?

More than one reason is at play here. The first is anxiety.

What are you googling and reading when you become aware of a lot of muscle twitching in your legs?

If it’s content that elicits anxiety, then the anxiety will lead to the fasciculations—and your legs are often a hotspot because they contain the largest muscle groups in the entire body: more fibers to receive random nerve impulses that fire them.

  • So are you googling ALS? Expect anxiety.
  • Are you googling another health symptom like PVCs or signs of melanoma? Expect anxiety.

Now, here’s another way to look at this. When you’re in a state of persistent anxiety (being at the computer for long periods, all while frantically jumping from one medical site to another, or perhaps engaged in a stressful e-mail correspondence with a family member), your body enters a “fight or flee” mode.

Certainly you’ve heard of this, the “fight or flight” response. This causes chemical changes in your body in anticipation of a fight against danger, or an escape from danger.

It’s really fascinating stuff: This response comes in handy when you’re confronted by a true threat.

It explains why Charlotte Heffelmire, 19, was able to lift a GMC truck up off the ground just enough to free her father Eric trapped underneath when he was lying beneath it for repairs when the jack slipped.

But the body can’t tell the difference between this kind of threat and the “threat” of anxiety from reading ALS sites.

The perception of a threat, real or imagined, causes the same changes in the body: increased heart rate, increased respiration, twitching muscles.

Think of the twitching as a way to put your muscles on stand-by for that fight or escape—they are gearing up, like a car engine being revved up before a race.

Another reason your leg muscles are twitching more so at the computer is because, quite frankly, you’re just plain more aware of the fascics.

Your legs are still or virtually still, making the twitching more noticeable, vs. if you were chasing after your preschooler outside—where your legs are engaged, masking any tiny little fascics, not to mention your attention is fully on the game you’re playing with your preschooler.

So now you have a few explanations for why your leg muscles seem to twitch away so much while you’re locked down at the computer. Perhaps your computer has become a conditioned stimulus for anxiety?

dr. dean

Dr. Dean, in practice for 35+ years and author of “The Magnesium Miracle,” is also a naturopath, nutritionist, herbalist, acupuncturist, lecturer and consultant.