There are many different treatments and modalities that your therapist may use to help you recover from an injury and get you back to your chosen lifestyle in the quickest and most effective way possible. EMS is one of the modalities that has been popular, but incredibly underutilized, for a long time.
EMS is short for Electrical Muscle Stimulation, and is the process of using external methods to activate your muscles and replicate the messages sent from your brain. While it sounds intimidating, EMS is actually a very simple process.
What Is Electrical Muscle Stimulation?
As you probably already know, your brain controls everything you do, say, think, and feel. This means that when you bend your leg, a message is sent from your brain to the muscle on the top of your leg (quadriceps) telling it to contract. Then a second message is sent to the muscle on the back of your leg (hamstring) telling it to relax.
When you feel pain, a similar thing happens. When you touch something hot, a message carrying that sensation is sent to your brain, telling it that the surface is hot and dangerous. Our brain instantaneously sends the same signals telling the muscles to remove the hand.
All of these messages are sent in under one-thousandth of a second, along tracks known as neural pathways. If you are over 18, you probably remember the old radios where you had to fiddle with a dial to find a radio station because each one had its own frequency. This is exactly how messages in your body work: each type of brain signal has its own frequency. Some of these signals include: pain, sharp, blunt, hot, cold, muscle contraction, and muscle relaxation.
A few years ago, scientists not only discovered these pathways, but they were also able to discover the “frequency” on which we send these messages. Not long after the research was developed further, EMS machines were honed and improved with the ability to use the same neural pathways to send messages to our brain and muscles telling them what to do and how to do it.
“EMS works along the same neural pathways to carry particular messages between the brain and muscles.”
When EMS is used, sticky pads are placed on the muscles that need to be activated (switched on) and the EMS machine is set to the right frequency to mimic the brain messages telling your muscles to contract.
Why Would Your Therapist Use EMS?
There are a number of reasons your therapist might use EMS. These include:
1. Pain Relief – When scientists discovered the frequency that our body uses to send messages telling us about pain, they also discovered that there were similar frequencies that could block those pain messages. Imagine that your pain signals are going along train tracks, and the station manager wants to stop the train. All they would need to do is open a gate across the tracks and that would likely stop the train. This is the case with pain. When you hurt yourself, you may have noticed that you automatically rub the area—that action of rubbing gives the brain different signals and blocks the transmission of the pain frequency. This is not the main use for EMS machines, but is definitely one to be aware of. EMS also provides the added benefit of pain relief for patients who are unwilling or unable to take oral pain relief such as anti-inflammatories.
2. Muscle Memory – It sounds slightly counterintuitive, but these neural pathways and messages we have been talking about create a type of permanent track in our mind. It’s a little bit like the way that scratching a ruler across a wooden table will at some point leave a slight divot. These “divots” are known as our muscle memory. This memory is why David Beckham can, after not kicking a ball for six months, know how to curl the ball into the top corner. His body simply remembers how to do it. The same thing applies to athletes that run fast: Once they have run a new personal best, their body “remembers” how to do it and, therefore, it’s easier to replicate the next time.
If you take this a step further, think about when you learned how to walk and move. You (usually) learned the correct patterns for human movement. These patterns are designed for us to be effective and efficient, and reduce the risk of injury. As we get older, we become lazy and start to develop poor habits, including bad posture. When this happens, some muscles become lazy and aren’t doing the work they should be.
The same thing happens when people develop an injury. For example, when you hurt your knee often, your thigh muscles (quadriceps) will “switch off” as a protective mechanism. The reason for this is that our body interprets pain as danger (usually correctly) and therefore, if moving your knee causes pain, it will try and switch off the muscles controlling your knee so you can do no further damage. Once the acute injury has been resolved, your quadriceps might not “switch back on.” This is the reason that athletes often develop a secondary injury after returning to sport; while the original injury has healed, the muscles are not as strong as they were. EMS is very effective in cases like this. The therapist ascertains which muscles aren’t working and uses the EMS machine to manually “jump start” them. I’ll talk more about how they can do that later.
3. Maximum Muscle Activation – This type of EMS treatment is similar to the one above, but is most commonly used in athletes. When you contract a muscle at any given time—for example, your quadriceps—you may only actually use 40% of the muscle fibers and electrical signals available in your leg. This happens mostly because our bodies are incredibly good at learning how to be effective. So, if using 40% gets the job done, then that is all it will use. The problem with this occurs when you are trying to push your body further than you have before. A weightlifter, for example, may try to lift a weight heavier than they ever have before. As a result, they need to recruit as many of the available muscle fibers and electrical signals as possible. Unfortunately for us all, it is not as simple as just asking your body to do it; your body has to relearn the action and learn to “switch on” the extra fibers, and do so in the correct order.
EMS should never be used as a replacement for training, but as an effective training tool. Share on XAn incredibly effective way to do this is to carry out the movement (in this instance, lifting the barbell) while having the EMS pads attached. The therapist can switch the machine onto the muscle contraction setting and turn it on while the athlete is lifting. After a period of time, this will train those dormant muscle fibers to fire up during that action. The therapist can then gradually reduce the external stimulation, as the muscle will have developed the memory to fire up and complete the action. The huge caveat is that EMS should never be used as a replacement for training but, rather, as a training aid.
When and How Should EMS Be Used?
EMS is best used as an adjunct to your training program; just one tool in your training arsenal. Suggested uses of EMS are:
To Aid Muscle Strengthening When in Pain or Injured
One of the most common situations in which a therapist will use EMS is when an athlete is trying to regain muscle strength, but physical movement or training is prevented by pain and/or acute injury. A common example of this is when a patient has had knee surgery. During the months and years leading up to the surgery, the muscles around the knee will have become increasingly weak either as a result of the muscles “switching off” as a protective mechanism or because the patient initially puts more strain on the other leg to avoid pain. The secondary cause of the muscle weakness is a patient leading a less active lifestyle in order to avoid pain and discomfort.
During the very early stages of rehabilitation (from the initial hours after surgery onward), the therapist aims to reactivate the muscles that have been affected during surgery and begin to trigger the muscle memory. They’ll do this as quickly after surgery as possible.
However, because the patient has been through a fairly traumatic surgery and may be in some discomfort, they may be unable or unwilling to carry out the therapist’s wishes. In this situation, the therapist can use EMS both as a mechanism to relieve the pain and, secondary to that, as a method to activate the muscles without requiring any (or very little) movement from the patient. This can be a useful way for the therapist to help the patient regain confidence in their ability to use the muscles with minimal discomfort.
To Enable Training When Fatigued and Prevent Injury
The most common cause of injury in any exercise program is fatigue, regardless of whether the program is designed to help you return from injury, strengthen to prevent injury, or simply improve a physical skill. When you become tired, a number of significant changes occur that greatly increase your chances of suffering an injury. These changes are:
1. Slower Signal Transmission – The signals we’ve been talking about throughout this article are sent at an incredible speed; however, as we become tired the speed of transmission slows. The cause for concern here is that fatigue prevents our body from having enough time to react in order to prevent injury. An example of this occurs if you are jogging and place your foot on a stone. Your brain will receive the message that your foot is on unstable ground and, as a result, amend your center of gravity and weight distribution and tell your foot to adjust its position, all in a fraction of a second. If, however, you are fatigued and this messaging is delayed, it is increasingly likely that you will not receive those messages in time to make the necessary adjustments prior to rolling your ankle and getting injured.
2. Movement Patterns – As we become tired, perhaps at the end of a training session, our movement patterns change. This is generally done as a mechanism to try and “cheat” the exercise and recruit extra muscles to help out. If you go to the gym and watch people in the weights area you will see this frequently. One of the most obvious examples of this is when people are doing bicep curls. In theory, the only movement in their body during this exercise is the lower arm, which they should bend and extend at the elbow. However, as the person becomes tired, you will see them “hitch”’ their shoulder to try and recruit extra muscles. They may even start to swing at the waist, hoping momentum will get the weight up! This creates cause for concern because these new adaptations are likely to result in an injury.
3. Motor Weakness – Simply put, when they’re fatigued, our muscles are tired. They are simply not capable of carrying out the demands we place on them. You may have experienced this if you have ever been on a long run or had a tough leg-training session and then tried to climb the stairs. Your legs likely felt like jelly and gave way under you. Other than the obvious risks that falling presents, you are at an increased risk of joint and muscle injury during this time because your muscles are overloaded.
Due to the reasons above, you have likely been advised not to complete any training when you’re fatigued. However, thanks to the invention of EMS, this is no longer the case. A therapist can apply EMS at the end of a session and activate the specific muscles, continuing to work on activation and tone while you are lying on a couch, at no risk of injury. This is often used in conjunction with visual rehearsal for maximum benefit.
EMS can even help activate fatigued muscles, without risk to the athlete. Share on XOverall, EMS is an extremely useful tool to aid a healthy or injured athlete, in conjunction with strategic and proven protocols.
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Hey, Can you recommend any machines for at-home use? I’d use it for rehabing my shoulder muscles after surgery.
Thanks
a new painpro device is brilliant for all the above. plese take a look it uses a triple therpay combining TENS EMS and microcurrnt ,
Where do you recommend we learn about EMS protocols as a PT/DC?
Is it possible to use this technique to tell a muscle to relax, where it is overcompensating?
My dad is in rehab and cannot stand very long his legs have become week due to wheelchair do you feel this could help him
Hi Bart,
The best advice is to ask your dad’s doctor or physiotherapist.
Christopher
I would have appretiated if the claims given here would have been quantified, and backed up by studies listed at the end. The evidence I saw on effects of EMG was a bit less than pictured here.
I am in rehabilitation after breaking my femur in six places. I had extensive surgery including rods, plates, straps and pins. Need to improve muscle mass, is EMS suitable for my type of injury?
When using EMS should I relax and let the machine do the work or should I actively flex with the EMS’ contraction.