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Duration:03:21
Uploaded:2018-02-01
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Have you ever been sitting down for a long time and had your legs fall asleep? It feels really weird and can make it hard to walk for a little while! So what makes your legs fall asleep, and why does it feel all prickly when they start to wake up?
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SOURCES:
http://www.sciencefocus.com/qa/what-pins-and-needles-0
http://www.bbc.com/future/story/20151116-why-do-we-get-pins-and-needles
https://www.ninds.nih.gov/Disorders/All-Disorders/Paresthesia-Information-Page
http://mentalfloss.com/article/21035/why-do-limbs-fall-asleep
♪INTRO♪.

Hey, Squeaks... (Squeaks squeaks). Oh, I'm ok.

My leg just feels kinda weird... It’s tingling, but in a way that feels prickly! [Squeaks Squeaks]. Oh yeah, you're right!

I think my leg is asleep! Maybe this has happened to you before, too. Sometimes if you’ve been doing something that presses on your arms or legs for a while, like sitting in one position or leaning on your elbow, it’ll start to go numb and you can’t feel as much with that part of your body.

Then, once you move so you’re not sitting or leaning that way anymore, your arm or leg starts to get all prickly, almost like you’re getting lots of tiny pokes all over, even though there’s nothing actually poking you. People sometimes call that feeling pins and needles. And that sounds a lot like what happened to me!

It’s something that can feel pretty weird, even though it happens to people all the time. When we say that an arm or leg fell asleep, we don’t really mean that it was asleep the way you are when you fall asleep at night. It’s just called that because you can’t feel much with it while it’s numb, almost like it’s sleeping.

And that tingling, pins and needles feeling you get when you shift your position is kind of like your arm or leg is waking up! You get that prickly feeling because your body is a little bit confused. You might already know that there’s blood moving everywhere in your body all the time, pumped through little tubes called blood vessels by your heart.

It’s really important that the blood moves through all the parts of your body, because that’s how they get energy so they can work properly. But when you sit in one position or lean on your arm or leg for a while, you’re pressing on those blood vessels and making the tubes smaller, so not as much blood can get through. And without enough blood, your arm or leg can start to go numb.

The reason you can feel something when you touch it is because of little things called nerves that are all over your body. Whenever you pick up a toy or touch something that’s hot or cold or hurts, these nerves are like little messengers that tell your brain all about what you’re touching. But the nerves only work well if they’re getting enough blood.

I must have sat in a way that was pressing on his leg for a few minutes, the nerves in my leg weren’t getting enough blood. So my leg stopped being able to feel as much — it went numb and fell asleep. But then I moved!

And once my body wasn’t pressing on his leg anymore, more blood started moving through it again and his nerves woke up. But nerves get a liiiittle confused when they wake up. At first, they don’t really know /what/ you’re feeling.

They start telling your brain that you’re feeling tiny little pokes, even though nothing is really touching you! That’s where the pins and needles feeling comes from. Pretty soon, your nerves get used to having enough blood again and go right back to normal.

So to keep yourself from getting pins and needles, you can just make sure you don’t sit or lean in one position for too long. And if you do get them, all you have to do is just wait. You can shake around the arm or leg in the meantime to help the blood get flowing again, but either way, the prickling will go away after a minute or two.

Whew, Squeaks! It feels like my nerves are finally getting back to normal! My leg is better now!

But now the next time I get pins and needles, I’ll know all about why it happens. And so will you! Thanks for joining us!

If you want to keep learning and having fun with Squeaks and me, hit the subscribe button, and we’ll see you next time here at the Fort! ♪Outro♪.