If you are experiencing chronic pain, a TENS Machine or transcutaneous electrical nerve stimulation device, may help to relieve back and neck pain that may be caused by trauma or continual strain. The body responds to such pain or injury with muscle guarding, an attempt to immobilize the painful area by tightening the muscles surrounding the injury. This impairs circulation in the affected area. The decrease in blood supply leads to a decrease in metabolism with an accumulation of waste products. A TENS (transcutaneous electric nerve stimulation) or TENS/EMS combination machine can help break this pain cycle by aiding in the healing process. We do recommend you read over How a Tens Units Works to fully understand how this alternative pain relief method works.