How do EMS Machines work?

Electro-stimulation machines (EMS) were primarily used for muscle recovery but are now generally used to tone and firm the muscles and, but do you know how EMS machines work?

EMS machines were previously reserved solely for elite athletes to aid recovery after a workout, but with time and little creative rebranding by fitness equipment companies, they have become very popular among those looking to improve muscle tone and strength.

Even Instagram influencers who want to tone and firm their glutes, have promoted EMS machines in the past. Glute machines are becoming very popular, however, how much truth there is behind their effectiveness?

What is an EMS machine?  

An EMS machine is a device with a set of electrodes that uses electric impulses to cause contractions in the muscles. It creates similar impulses that our central nervous system sends to control the contraction and relaxation of the muscle. An EMS machine allows you to move easily so you can do other exercises. You can find an example of EMS machines here. 

Electrostimulation is the result of the advancement of research in sports and medicine, it can be easily adapted to each user and can be fully customized. 

More and more physiotherapists include in their rehabilitation programs the use of electro-stimulators to reduce the recovery time and activate muscles after injuries, edemas and muscle contractions

Also, EMS machines are used to improve blood circulation because it helps to relax muscle fibres and reduce stiffness of joints that hinder freedom of movement. The areas that best respond to electrostimulation in the improvement of circulation are the back and cervical areas since they are the most vulnerable areas to contractures.

These effective devices are designed to reduce the issues mentioned and restore the muscle functionality and the stability of the joints for people who are in the rehabilitation process, for example, someone who has suffered an ACL (Anterior cruciate ligament) injury, after the surgery, it’s common that the quads get weakened and to wake them up EMS machines are employed. 

However, if you suffer pain from an injury then TENS (transcutaneous electrical nerve stimulation) is adequate therapy, it is focused on reducing the pain by low-intensity electrical impulses, without the need for medication. 

Do they really build muscle?

There are studies such as the one done by Sports Sci Med[1], in which 24 adults stimulated their abdominals 5 days per week (20-40 minutes per session) for 8 weeks (using EMS machines) and refrained from engaging in any additional exercise during the study. The results showed that the EMS helped to firm and tone abdominals.

Can I lose my weight with EMS machines?

There is a common misconception that EMS machines can help you to lose weight.  The aforementioned study found that some of the participants reported a reduction in their waist circumference by 3.5 cm, however, there was no significant change in the bodyweight of the participants.

So what can EMS machines be used for?

  • To strengthen and tone your muscles if you mix EMS machine usage with active exercises and a suitable diet. 
  • To aid recovery and promote faster recovery time. 
  • To increase natural collagen which can boost muscle mass, relieve joint pain, prevent bone loss, etc.


To summarise, an EMS machine can help your muscles to recover and tone, but they can’t replace regular resistant training or cardiovascular when looking to build muscle or lose fat.