Why Do Our Limbs Fall Asleep?
Our limbs fall asleep because of our nerves. Through nerves, our brain can communicate with our limbs. When we cross our legs or just sleep on an arm for very long time, we apply the pressure causing the nerve pathways and its surrounding arteries (carries oxygenated blood) to squeeze due to which the nerves are not able to work properly, as the arteries fails to supply the required nutrients to the nerves, as a result, the signals sent by our brain through nerves don’t reach there so we cannot move our limbs and it feels like it has fallen asleep.
Do you ever get this weird sensation in your legs when you’ve been sitting cross legged for too long? The kind of tingling, prickling feeling that makes it hard for you to walk for a while.
Sometimes when you’ve been doing something that presses 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 won’t be able to feel as much with that part of your body. You start to get up from your seat and all you feel from one foot is this uncomfortable numbness. Or you wake up in the middle of the night and you can’t move your arm at all. It’s just kind of flopping around behind you.
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’ve got lots of tiny pokes all over, even though there’s nothing actually poking you. People sometimes call that feeling pins and needles. It is something that can feel pretty weird even though it happens to people all the time.
Whats make your legs fall asleep?
So why does this happen? What makes your legs fall asleep? And why does it feel all prickly when you start to wake up?
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 is just called so because you cant feel much with it while it is numb, almost like you are sleeping. And that tingling pins and needles feeling you get while you shift your position is almost like your arm or leg 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 is really important that the blood moves through all the parts of your body. That is how they get the energy to function 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.
Why can’t your hands feel anything?
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.
If you had sat in a way that the blood vessels in your leg are being pressed on , then the nerves in your leg weren’t getting enough blood. See, when you sit, especially if you’re sitting on a hard surface you’re applying pressure to your legs.
When you apply that pressure you can actually block communication between the nerves in your leg and your brain. That way your nerves can’t tell your brain how your leg is feeling and your brain can not communicate with your nerves to tell them, “move your legs”.
What’s more, you’re not just cutting off communication to your nerves but you’re cutting off communication to your brains too.
Your blood delivers vital nutrients to your nerves so that they function correctly and when they’re not getting any nutrients because the blood flow is cut off, they start going berserk.
The sum total of all this is that because there is no communication between the brain and the nerves, and the nerves aren’t getting the nutrients, they start behaving crazy. And when you finally stand up they send all sorts of strange signals to your brain which accounts for pins and needles. So you’re leg stopped being able to feel as much – it went numb and fell asleep.
But then you moved and once your body wasn’t pressing against your leg anymore, more blood started moving through it again and your nerves woke up.
But nerves get a little confused when they wake up. At first they don’t really know what they’re feeling. They start telling your brain that they’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 that you don’t it 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 get the blood flowing again, but either way the prickling will go away after a minute or two.