EMS, how often?

How often should you do EMS?

When I first started exploring WB-EMS I had the opportunity to go to Brazil and visit the studios of a successful franchise there. The head trainer put me through four (!!) EMS training sessions in just three days. When I asked about creatine kinase (CK) levels and the risk of rhabdomyolysis, he laughed, and replied back: “What do you really know about rhabdo?”

At the time, not much. 

Today let’s look at the primary safety concerns with EMS fitness, and what the recommendations are.

CK levels

CK, short for creatine kinase, is an enzyme found mainly in muscle tissue and the brain. Its main function is to help produce energy for muscle contraction by catalyzing the conversion of creatine to phosphocreatine.

There are three main types of CK: CK-MM, found mainly in skeletal muscle; CK-MB, found mainly in the heart; and CK-BB, found mainly in the brain.

When muscle tissue is damaged, such as through strenuous exercise, trauma, or disease, CK leaks into the bloodstream and can be measured through a blood test. Elevated levels of CK in the blood can indicate muscle damage, and the level of CK in the blood generally correlates with the severity of muscle damage.

Some of the risks of having elevated CK levels include:

  • Muscle damage or injury: Elevated CK levels can be a sign of muscle damage or injury, such as from a muscle strain or tear, strenuous exercise, or a medical condition like rhabdomyolysis.
  • Heart attack: In some cases, elevated CK-MB levels can be a sign of a heart attack, as the heart muscle can also be damaged and release CK into the bloodstream.
  • Medications: Certain medications, such as statins used to lower cholesterol, can cause elevated CK levels as a side effect.
  • Genetics: Some people have naturally higher levels of CK due to genetic factors, which may not necessarily be harmful. However, consistently elevated CK levels should be evaluated by a medical professional to determine the cause and any potential risks.


CrossFit did for rhabdomyolysis what Sugarhill Gang did for hip hop: made it mainstream.

Nobody in the fitness industry was talking about rhabdo until CrossFit exploded nationally. 

It is still an uncommon condition only affecting 26.000 people per year, that’s 0.007% of the population, but as trainers, we’ve all heard of it. I’m not a CrossFitter, but I believe they have modified their program to avoid injuring their members as often.

Rhabdomyolysis is a condition where muscle tissue breaks down and releases its contents into the bloodstream. The breakdown of muscle fibers leads to the release of various substances, including myoglobin, creatine kinase (CK), electrolytes, and other proteins.

The mechanism of rhabdomyolysis can be caused by several factors, including physical injury or trauma, excessive exercise, muscle compression, medications, drug abuse, infections, and electrolyte imbalances.

When muscles are damaged, the cell membranes rupture, and the contents of the muscle cells are released into the bloodstream. This can lead to an overload of myoglobin, a protein that carries oxygen in muscle tissue, in the kidneys. Myoglobin is not supposed to be present in the bloodstream, and its accumulation can cause damage to the kidneys and lead to acute kidney injury.

Elevated levels of CK in the bloodstream are a key diagnostic feature of rhabdomyolysis. When CK is released from damaged muscle tissue, it can cause damage to other organs, including the heart, liver, and lungs, leading to additional complications.

EMS fitness, CK levels, and rhabdo:

EMS fitness is known to elevate CK levels, specifically CK-MM levels. This is a well-known fact and has made many doctors in other countries a bit cautious about recommending EMS workouts. 

There are some known cases of rhabdo after EMS training sessions, most notably in 2015, when 2 soccer players needed to be hospitalized. I’ve heard many reports of these initial incidents, and other scary stories from EMS trainers when they first started. In many cases, it seems there were no clear recommendations on what parameters to use with electrical muscle stimulation, and what precautions to take, in addition to many other factors such as lack of hydration, overtraining, not allowing enough recovery time, and so on.

In 2016, Wolgfang Kemmler, the Godfather of EMS research, put forward some recommendations in order to try to regulate this new and emerging niche of the fitness industry. In summary, EMS fitness sessions at first should be spaced out by at least a week and not take muscle to maximal exertion. 

In a later study, in 2022, Kemmler et al. found that CK levels increased a lot more in younger populations but mostly within the first 3 weeks, and by week 8, levels were back to normal. In older populations, CK levels didn’t rise very high at any point. This means that for our target demographic, which is mostly people over 50 years old, EMS workouts are very safe.

The explanation for the differences between younger and older populations using EMS fitness, seems to be related to the amount of type 2 muscle fibers. You can read more about type 2 muscle fibers here, but in summary, they’re responsible for strength, and they’re the first ones we lose as we age. There are a few other explanations, but one of them may also be additional activities around EMS workouts. 

Our recommendations:

In line with industry standards and the manufacturer’s guidelines, we respect not exceeding doing more than 2-3 EMS workouts per week. 

2x/week for people that don’t lift weights

Most of our clients do not enjoy lifting weights on their own, so EMS fitness becomes a substitute for resistance training. This means our clients can still enjoy all other (more cardiovascular) activities such as walking, hiking, cycling, swimming, playing pickleball, tennis, and so on.

3x/week for people that don’t lift weights and do any cardio

Not everybody has the ability or time for consistent cardiovascular exercise. In this case, we would recommend doing 3 sessions per week, where one session or half of 2 sessions will be devoted to cardio-type exercise with the remainder focusing on strength.

1x/week for people that are lifting, and doing cardio

People that lift weights and play sports consistently may still benefit from one EMS session per week in order to strengthen the core, fix muscle imbalances, and work with a trainer for possible corrective exercises.

Related articles:

Active Aging – what we should focus on as we age

EMS and how it fits with other modalities

If you are interested in learning more about EMS book a free consultation with me here: https://calendly.com/conradfitness/30min


Director of Education and Technology



Bodybuzz combines Certified Personal Training with Electrical Muscle Stimulation, giving your body a deeper, safer, and more effective workout. 20 minutes twice a week is all it takes!

Our personal trainers will guide you through a custom EMS workout designed specifically for you. Whether you’re looking to build strength, lose weight, get toned, or recover from an injury or illness, we offer a safe, low-impact solution to help get you there.

EMS has now been FDA-cleared for use in the US and we are proud to be one of the first companies to introduce this technology. It is a full-body workout that uses a special muscle stimulating suit that sends low-level impulses to your major muscle groups to trigger muscle contractions. It’s a unique sensation that is painless and invigorating. EMS workouts are designed to achieve optimal conditioning, burn fat, develop strength, build muscle, tighten skin, combat cellulite, jump-start your metabolism and restore your body’s natural balance.