When you sit on your leg, the blood circulation gets cut off from the lower leg. In other words your blood stream is being pushed down by your other leg. The tickling feeling is your nervous system. To get it to stop just take your leg off the other and run a little
This is definitely a strange sensation! you get up out of your seat, and all you feel from one foot is an uncomfortable tingling.And then, as your body part "wakes up," the strange tingling intensifies.Usually, you feel this familiar sensation after you've been putting pressure on part of your body by sitting on a foot or sleeping on an arm, etc. When you apply this pressure for a prolonged period of time, you actually cut off communication from your brain to parts of your body. . Once you do move your foot, stretch your legs, or roll over off your arm, the nerve impulses begin to flow properly again. You don't regain feeling right away, however. There is a certain amount of re-adjustment time before the nerves transmit impulses correctly again. This increases the intensity of the tingling, causing the familiar "pins and needles" sensation.