When your leg or arm falls asleep, it’s not that you’ve cut the blood off to your limb, as most of us were told.
It’s a pinched nerve. When you bend your arm or leg, the muscles actually constrict nerves.
If left in that position for a long enough time, then moved, your limb will feel like someone has come in the night and sewed someone else’s limb to your body.
As the nerve begins waking up, you will feel pricks like ant stings until the nerve is back up and running as usual.
If you sit for hours on end with a major leg nerve constricted, the nerve can actually become damaged and cause parts of the foot to stop functioning properly.
However, uncrossing your legs, changing your sitting pattern, and keeping pressure off the damaged nerve will bring everything back to normal in a few days or weeks.