If you've been sitting in class for a couple hours, or working at a desk all afternoon, you might find yourself getting a little restless.
You might fidget, stretch a little, or start jiggling your leg up and down. 
We all get a little jittery after sitting for too long, but some people get an irresistible urge to move, called Restless Leg Syndrome, or RLS, and it can severely affect their daily lives.

RLS is a Neurological condition that creates a throbbing or pulling sensation in the legs, and an overwhelming need to move them.  

These sensations can get worse when you sit or lie down, making it really difficult to fall and stay asleep. (0:31)

But, haven't we all had some uncomfortable nights of tossing and turning in our bed? Like, if you're too hot, or sick, or just stressed out about that thing you have to do tomorrow?

Because of this, some people think that RLS isn't a real problem- that it's just a symptom of something else, like anxiety. (0:44)

But it turns out, doctors and scientists have plenty of evidence that this condition is its own thing. For one, it seems to run in families, so it could be a genetic disorder. 
Also, RLS has been linked to low iron levels in the blood, which indicated the bigger problem:
(1:00) Problems with dopamine signaling in the region of your brain known as the basal ganglia. 

(1:06) Your body needs iron to create dopamine, which is an important chemical used to send signals within the brain. In the basal ganglia, dopamine is part of a pathway that makes decisions about starting muscle movement. 

(1:14) So, when you have normal amounts of dopamine, this pathways sends message to other parts of the brain, so you can make smooth, controlled movements. 

But, when you don't have normal amounts of dopamine, the messages get messed up, and you can develop movement disorders like RLS, or Parkinson's Disease with throbbing or shaking muscles. 

Many people with mild RLS might not even be aware they have it. But, if it's more serious, what can be done to help?

(1:33) Sometimes, doctors suggest that sleeping with a vibrating pad underneath your leg to counteract the uncomfortable muscle sensations of RLS. 

If you have low iron levels, you might be prescribed iron supplements.

(1:43) Medications called dopamine agonists can trick your brain cells into thinking they've received dopamine signals when there actually isn't enough of it. This can fix that pathway and dramatically improve the painful sensations of RLS.

So there you have it- sometimes, jiggly legs and sleepless nights aren't just passing jitters. 

But, if you've been hunched over your computer watching YouTube for a while... you might want to take a stretch. :)

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