Health

What’s Really Happening When Your Hands or Feet Fall Asleep?

You know that dull, pins-and-needles sensation you get when your limbs fall asleep? Turns out, it has everything to do with our nervous systems. Here's why our hands and feet keep snoozing on us and what we can do to wake them up.

By Donna SarkarJun 1, 2021 2:00 PM
sleepy limbs
(Credit: aleks333/Shutterstock)

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It happens to the best of us: You’re sitting in the same position for a bit too long (perhaps slumped over your computer) and suddenly, you can’t move your hands or feet. It usually takes a few minutes to return to normal, but after some stomping and shaking, they magically wake up.

When our limbs decide to take a snooze, we often experience numbness, dull pain or even a pins-and-needles feeling. As it turns out, these abnormal sensations have a medical name: paresthesia. Symptoms of paresthesia are typically temporary and can usually be resolved by standing up or switching positions.

So, after some fuss, you've finally gotten your hand or foot to wake up and the weird sensations disappear ... until it happens again. What is really going on when a body part falls asleep?

Inside the World of Sleepy Limbs

To understand paresthesia's underlying causes, we have to first explore the nervous system. Breathing, walking, thinking and feeling — it manages all of these critical functions. At the center of it all sits the brain, which serves as the control system. Meanwhile, the spinal cord acts as the bridge from the brain to the rest of the body. Millions of nerve cells (80 million, to be exact) can be found throughout the body. These cells, also known as neurons, send messages to the brain to indicate how the body is doing. In turn, it can interpret them and take action.

According to the National Institute of Neurological Disorders and Stroke, when limbs fall asleep, it's likely due to sustained pressure on a nerve. For instance, sitting in one position for too long or sleeping on your arm can irritate your nerves. This prolonged pressure can temporarily cut off communication and blood supply. When nerve cells fail to function properly, we feel the numbness and pins-and-needles sensation. While it may sound serious, temporary paresthesia is not a cause for worry.

But chronic paresthesia may require medical attention. If symptoms persist over extended time periods, neurological damage may be to blame. Nerve damage typically arises from a host of different possibilities, including infection or inflammation. An easy way to distinguish between chronic and temporary paresthesia is to check if you're able to move the body part that's currently slumbering. With temporary paresthesia, you may lose sensation, but can still move the given area. Chronic paresthesia, however, results in loss of movement and sensation.

How To Wake Up Your Limbs

A simple solution for sleepy limbs is to walk around for a few minutes. By jostling the body parts that have fallen asleep, blood flow is restored and the pressure is alleviated. If your limbs are taking too long to wake up, another solution may be to loosen the muscles in your neck. Massaging this area can help reduce muscle tension and open nerve pathways while also promoting blood flow.

Dehydration can often induce paresthesia, so drinking plenty of water when you experience sleepy limbs can help remove toxins and flush out the lactic acid buildup that causes painful and sore muscles.

More often than not, your body parts snoozing on you is ultimately more annoying and inconvenient than dangerous. In fact, it happens to most people and can be resolved rather quickly. The bottom line: To avoid the dreaded feeling, remember to stretch and change positions often.

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