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TENS vs EMS: What is the difference?

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Pain management doesn’t automatically mean drugs. Many of us simply want to stay away from drugs and minimize their use, due to the clear and significant risks associated with common prescription pain medications.

And there are several alternative pain management solutions available. One option that is rapidly increasing in popularity is the use of TENS/EMS units. These little wonders look like an iPod with a bunch of cords attached. At the end of each cord is a small pad. You place these pads on certain locations on the body, and mild electric currents run through you, relieving pain.

This article looks in depth at the technology of electrotherapy, and clarifies the differences in TENS vs EMS treatments. We also suggest a few options to check out.

What Is Electrotherapy?

iReliev TENS EMS Unit

Electrotherapy is a treatment used in physiotherapy to help deal with pain and promote the healing of the tissue. It makes use of electrical energy to help distract or slow down pain messages to the brain.

It can help with damaged tissue by stimulating it to heal faster.

There are different machines that can be used in electrotherapy. Two of the most commonly confused are the TENS (Transcutaneous Electrical Nerve Stimulation) and EMS (Electrical Muscle Stimulation). Though they are similar when it comes to making use of electrical impulses, their effects and uses are different.

Many machines on the market make use of both of these systems, including the iReliev unit shown above. See our article on the Best TENS/EMS Units to learn more about individual options.

Let’s go through the differences now.


Dual Channel TENS EMS Unit

EMS and TENS machines are different from each other, though many devices like the Belifu Dual Channel TENS EMS Unit shown above (our favorite unit), are multifunctional. The two systems differ from each other mainly due to their application.

TENS machines are what you want if you want to deal with the pain. While an EMS machine can be used to aid in muscle stimulation, which can be quite useful for athletic training and longer-term strengthing.

TENS machines are great because they can help you deal with the pain without using any addictive drugs or any drug at all. EMS machines are used to help with damaged muscles, especially after an injury or an accident.

They are very useful in the rehabilitation phase because they aren’t just focused on providing pain relief. EMS units help strengthen muscles, which may result in the disappearance of pain in the longer term.

Aside from the different uses, these systems also differ in how they function. The TENS units, which are focused on pain, work by preventing the pain from being felt. This is accomplished by interrupting the signals sent to the nerves.

On the other hand, EMS focuses on causing the muscles to contract. This contraction builds muscles just like exercising does. But don’t expect to get a six-pack due to EMS!

muscle building

Now that we’ve covered the basic difference between the EMS and TENS are, let us focus on each of them so you can better know which one is more applicable for your condition.

What Is EMS?

EMS stands for Electric Muscle Stimulation. And as the name implies, it stimulates the muscles to contract by using an electric pulse. This electric pulse is created by the EMS machine and reaches the body through the pads that stick to the skin.

With EMS, the pads or electrodes are placed on the skin in the area where the muscle you want to engage is. The electrical charge is given off by the unit, and is transmitted through the wires and the pad. It reaches the muscles and causes them to contract.

The contracting action of the muscle is similar to the contraction the muscle does when exercising. The EMS machine essentially stimulates specific muscles to exercise.

Uses Of EMS

Stimulating the muscles to contract is very useful in therapy. It helps with swelling and inflammation, and it also targets specific muscles that cannot safely be exercised yet due to injury.

Sometimes, the joints aren’t healed yet so manually exercising the muscles cannot be done. Also, if the joints aren’t fully healed, premature exercise can cause further dislocation and injury if you push yourself into exercising.

EMS’s ability to reduce inflammation helps restore muscle function and speed recovery. This will also help prevent causing pain or damage to other tissues or joints that are impacted due to inflammation.

Physical therapists use EMS units not only to help with muscle recovery but also to help reduce muscular pain. This is because EMS can help deal with the edema and muscle spasms that can occur after an injury.

Contracting muscles also heal better due to improved blood flow through them.

EMS also prevents the muscles from getting too stiff and locking in place due to lack of use during injury This process eases muscle tension so that stiffness, even in the joints, is reduced. This can help improve the range of motion in the area.

EMS units are very useful in the following situations:

  • Prevent or lessen the occurrence of muscle spasms.
  • Improve blood circulation on specific local areas of the body
  • Prevents further muscle atrophy.
  • Improvement of muscle tone and strength.
  • Improvement of range of motion.
  • Prevention of venous thrombosis, especially after going through a surgery.

What Is TENS?


The acronym TENS means transcutaneous electrical nerve stimulation. From the name, you’ll notice that it doesn’t stimulate the muscles. Instead, it stimulates the nerves to aid in pain relief. It sends out non-painful impulses that go through the skin to the nerves. This is very helpful when someone has a chronic health condition or a nerve disorder that makes them suffer from pain.

Many like this alternative to pain medications because there is no drug or chemical used. It just uses electric pulses that can help with the stimulation of endorphins that prevents the pain signals from reaching the brain. The endorphins also help enhance the mood, which is very useful for patients who suffer from chronic pain. There are different theories on how EMS does that.

The TENS machines, like the AUVON TENS/EMS Unit, comes with multiple modes that can be selected and adjusted depending on the individual who’s using it. Although it is effective at pain relief, the level of relief will still vary from one patient to another. This may be due to the individual’s pain tolerance and condition.

Use of TENS

TENS units are best for the following:

  • Those who have chronic or acute pain.
  • For patients who are in pain after their surgery
  • Those who have regular migraines or headaches.
  • Athletes who had sports injuries that causes pain.
  • People who have arthritis, bursitis or tendonitis.
  • Cancer patients who are in pain.
  • Those who are looking for a pain relief alternative.

Which One Should I Use?


The choice on which one to use would depend on your goal when purchasing the device and what condition you’re in.

The bottom line, though, is that the vast majority of units on the market do both, such as the HiDow XPD-12 TENS + EMS Combination Unit shown above (we reviewed that one here). Most units are capable of running both TENS and EMS treatments.

TENS units are best for pain management and EMS units are best for muscle recovery. Although both can still help deal with pain, they differ on how they go about treatment.

When it comes to pain, TENS units focus on the nerves and on preventing the pain signals or inducing the production of endorphins. EMS on the other handwork on the muscles and prevents spasm or inflammation that can also cause pain.

Some people prefer the TENS units because they’ve used it before. Also, if you are taking medication that’s for nerve pain, a TENS unit would be a more suitable choice for you. Muscle pain, due to spasm and stiffness or muscle tension is best for EMS units.

One isn’t better over the other. It is just a matter of application. Some people even use both TENS and EMS in one area of their body to find positive results. This is especially true for those who have chronic pain that involves both the muscles and the nerves. Combination treatments can be used to address the multiple causes of pain.

Ultimately, it’s best to choose a combination unit that you can experiment with. See our article on the Best TENS Units (all of which are combination TENS/EMS units) to find the right option for your needs.

Frequently Asked Questions:

Does EMS burn fat?

The main function of EMS is to stimulate the muscles to contract so it can be strengthened. Although it effectively does, it does not burn fat like you would when you are exercise. When you exercise, you deliberately contract and relax your muscles while using energy. Your fat stores are burned when you don’t have enough energy readily available but is still working out. It does help with toning the muscle but it does not burn fat.

Can you use EMS in the chest area?

EMS makes use of electric pulses and can be used in most parts of the body. However, most advice against using it on the neck as well as the chest area due to the electrical current affecting the heart. It is possible for a rhythm disturbance to occur when it is used in the area near the heart. Although the risk isn’t great, you still shouldn’t risk it. Also, most EMS units will advise you against using it on the chest.

Can you overuse a TENS unit?

TENS machines do not require prescriptions to be used but using them should still be under the advice of your doctor or physical therapist. They will be the ones who can advise how often and for how long you should use them. Overusing TENS machines can cause the area to be sore. Also, using too high levels can lead to unpleasant sensations and muscle twitching.

What is the effect of TENS on muscles?

The TENS units use electrical pulses that target the nerves The electrical pulses can also stimulate the release of endorphins. Even if the electrical pulse reaches the muscles, it does not cause it to contract. That is why it cannot be used for muscle building or growth.