Posted by Conchita Van Meurs
What is TENS? Understanding the Basics
TENS stands for Transcutaneous Electrical Nerve Stimulation. Simply put, electrical currents are used to quiet nerves or to stimulate muscle fibres.
There are two main theories as to why it works. First, that the stimulation causes your body to release endorphins, your body’s natural pain killers. The second, is that stimulation stops the receptors in your brain from receiving pain messages. So, although you may still have the injury, you simply do not sense it and therefore become temporarily pain free.
TENS offers a safe, drug free way to manage pain and is highly recommended by healthcare professionals. It may eliminate or reduce your need for pain medications. Reducing your use of over the counter drugs or prescriptions can benefit your overall health and diminish your risk of drug conflicts.
TENS can manage pain associated with:
Is TENS Safe?
Yes. The amount of electrical current being used is not enough to shock you or harm the skin. However, patients with cancer, pregnancy, epilepsy or pacemakers should avoid electrotherapy.
Electrodes should never be placed on the face, front of the neck or on the heart, as these regions may be affected by the current. Electrodes should not be placed on open wounds or on any region where you may have limited sensation.
Does TENS therapy hurt?
No. Electrotherapy units are set to specific frequencies designed to reduce your pain, not increase it. Some patients become sensitive to the “tingling” effect on their skin with long treatment times, however simply turning down the intensity can often eliminate this effect.
For best results, TENS therapy should be conducted at an intensity that is “tolerable” but not “comfortable”.
How is it done?
Electrodes are placed on the skin, either directly over the painful area, along key points of the nerve pathway or on the muscles. A small amount of electrical current is sent through lead wires to the electrodes.
Single channel units use two electrodes. Dual channel devices use four. Each channel is a lead wire with a positive and negative electrode.
How long does TENS therapy take?
Individual sessions typically last between 15 - 30 minutes depending on the specific therapy being applied. Patients often report immediate relief after each session, with results lasting for hours after the session is over. This makes electrotherapy an effective way to manage pain.
How often can I use a TENS device?
You can use your TENS machine as often as you like to manage your pain, as it triggers your body’s natural response. There are no known side effects to regular use other than some potential irritation where the electrodes are placed.
Which TENS device should I choose?
For personal use there are two primary TENS styles in the market. Analog TENS units have rotary dials and switches. These typically require the help of a healthcare professional who will set the individual settings for you and your specific condition. Once these are set, the cover of the unit is closed and all you would need to worry about is turning it on and setting your power levels.
Digital, pre-programmed units typically come with a variety of programs already built-in to the unit. These are often listed by conditions or body parts. These require less help from a healthcare professional but may require you to input more settings each time you want to use it. Some devices, feature a LOCK button so that you can leave your program settings locked for future use.
In clinical environments, TENS is almost always offered with other electrotherapy waveforms. Large clinical devices usually include Interferential and Electrical Muscle Stimulation (EMS/NMES/FES) and other waveforms such as microcurrent, galvanic, Russian muscle stim etc.
If you are interested in beginning TENS therapy, we recommend you talk to your healthcare provider. As mentioned in the beginning, there are some conditions and circumstances for which TENS therapy is a “Counterindication” and should not be used. Your healthcare provider can also help you establish the settings ideal for the pain you are trying to treat.