Does my arm really ‘fall asleep’?

Published on August 25th, 2011
Does my arm really 'fall asleep'?

You know that horrible feeling:  feels heavy and almost dead, and as you slowly move it with difficulty, that aching, tingling sensation known as “pins and needles” sets in. We know you know what we’re talking about!

What’s happening in your arm goes by the technical name of paresthesia. In most cases, paresthesia occurs when pressure from sleeping or sitting blocks the blood flow to nerve fibres in some part of your body. Nerves need fresh oxygen and nutrients to function properly and, without them, they go a bit haywire.

While snoozing, the weight of your head puts pressure on the blood vessels that thread through your arm, cutting off circulation. This prevents energising sugar and oxygen from reaching the nerve fibres. This blood “drought” sabotages the normal flow of sensory data to the brain as the “thirsty” nerves start firing off messages at random.

These random messages equate to pins and needles! Talk about an internal alarm….

Pic credit: Her wings

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