TENS, EMS, both of these techniques use microcurrents to relieve pain.
What is transcutaneous electrical nerve stimulation (TENS)?
TENS is a technique that uses electrical currents to relieve pain. Transcutaneous electrical nerve stimulation means: sending small, low-voltage electrical pulses to specific nerves through electrodes placed on the skin, with the goal of changing the way neurons send signals and preventing pain signals from reaching the brain.
What is Electrical Muscle Stimulation (EMS)?
EMS is a technique in which electrical currents are used to stimulate muscles to achieve a specific effect. Electrical muscle stimulation is small, low-voltage electrical pulses delivered to a muscle through electrodes placed on the skin to cause the muscle to contract.
This muscle contraction has two distinct purposes: to relieve inflammation and to strengthen the muscle without involving the nervous system, thus avoiding pain and fatigue.
TENS
A TENS machine, also known as a TENS unit or neurostimulator, consists of an electrical pulse generator connected to electrodes placed on the skin. It works by delivering small electrical pulses to stimulate the mechanisms that cause pain.
TENS machines work in three different ways:
- Blocking the transmission of pain signals to the brain.
- Stimulates the production of endorphins (which are a natural pain reliever).
- It improves blood circulation.
TENS machines are used to relieve nerve, muscle, or joint pain, which is often chronic and takes many forms, including inflammatory arthritis, back pain, foot pain, contractions during childbirth, or post-operative pain. Migraine pain can be relieved by a specialized TENS machine.
EMS
The EMS machine works in much the same way, it also consists of an electrical pulse generator connected to electrodes that are placed on the skin around your muscles for treatment.
EMS also works by sending small electrical pulses, this time delivered directly to the muscles, causing them to contract. The muscles contract and relax repeatedly, which helps to improve blood circulation, which in turn has the following effects:
- Relaxes the muscles
- Minimize any inflammation
- Prevent muscle atrophy
- Accelerate muscle healing
- Stimulates muscle growth
EMS machines are used to relax or strengthen muscles, for example in cases of muscle spasm, poor blood circulation (especially in the back and neck), muscle atrophy after illness, or as part of rehabilitation after injury. Therefore, they are more often recommended for the relief of muscle pain.
Athletes also sometimes use EMS to recover faster from injuries, as electrical muscle stimulation allows them to (re)build muscles without much stress and to exercise muscles they may not use much.
The main differences between the two
Transcutaneous electrical nerve stimulation (TENS) machines stimulate nerves solely for the purpose of pain relief, while electrical muscle stimulation (EMS) machines stimulate muscles for strengthening and rehabilitation purposes.