Why is my body twitching?

I also have this problem, especially when I am very tense and stressed out. My doctor said its because while my body is trying to relax or sleep, my mind is still going a million miles an hour. Also I do believe I have restless leg syndrome which makes me feel like I need to move my legs all the time and they tingle and jump. My condition has much improved since getting a job that doesn't require standing 9 hours a day.