TENS
A technique for relieving acute and chronic pain. A weak electrical current is discharged through electrodes placed at strategic points on the skin to stop the messages from pain receptors reaching the brain. One theory suggests that this current stimulates large nerve fibres in the spinal cord to inhibit or block the transmission along small pain fibres. Another theory proposes that it stimulates the release of chemicals, such as endorphins, that decrease the perception of pain in the same way as opium and morphine. TENS has been used effectively to control the pain caused by some sports injuries, but, because the devices use pulses of short duration, the technique is not well suited to relieving muscle pain.
