The bed of nails was originated in India for relaxation exercises,meditation and yoga for thousands of years. There are many factors that indicate the pain relief is due to the pressure from the Acupressure mat activating the body's own production of endorphins, "natural painkillers", which are also released during exercise. Endorphins give pain relief and a sense of physical well-being. Another substance which is probably also released is called oxytocin that produces relaxation. You wind down and find it easier to fall asleep