Diploma Physiotherapist Joachim Winter in an Expert Interview on the Topic: Medium Frequency Therapy as a Popular Supplement in Competitive Sports, for Muscle Building, and in Pain Therapy

Electrotherapy has become an established complementary measure in various fields such as pain therapy, recovery in elite sports, and muscle building. Its application should be careful and non-abusive. Medium-frequency therapy plays a key role in innovative electrical stimulation therapy.

myostyle: Mr. Winter, you began your career as a Radar Technician. How did you eventually find your way to physiotherapy?

J. Winter: Since I am very enthusiastic about technology, I initially trained as a Radar Technician in the 1970s. However, at that time, the advancements in electrical engineering were idealized, and I quickly realized that the subject was too dry and theoretical for me. I missed human relationships and personal interaction.

Since I did not know exactly which career path I would take, I first completed a social internship in a nursing home and later trained as a massage therapist and medical bath attendant at a school in Freiburg. These areas also did not fully satisfy me, so I decided to pursue training as a Physiotherapist. After that, I studied Physiotherapy in the Netherlands and completed a Master's degree in Physical Medicine Sciences.

myostyle: Your specializations as a Physiotherapist include electrotherapy and neurophysiology. Could you briefly explain what these are?

J. Winter: Electrotherapy is based on the different applications of electrical currents to the body and their effects. Neurophysiology, on the other hand, explains the processes in the body—more specifically, the levels of brain structures and the neural system where perceptions and reactions are connected, as well as the feedback loops used to ensure the corresponding body functions and reactions. This helps to economize, optimize, or modify actions and reactions. Developmental processes of evolution and embryology play a significant role here: for example, the successive steps of physical and neural development and the complex interrelationships of physicality, functionality, and emotionality.

myostyle: You have co-authored a book with other researchers about the Revolution in Electrotherapy. Can you tell us a bit more about this revolution?

J. Winter: I come from the field of electronics, and I found many of the explanations I received during my vocational training very questionable. However, I accepted them at the time because I was inexperienced and didn't know any better, but I had doubts about whether the explanations presented were true.

When I later delved deeper into this topic, I discovered that many of the descriptions and explanations originated from the early to mid-20th century and were never validated for their accuracy. The mentality was: "It somehow works, and the explanation seems plausible at first glance." People were generally content with assumptions and speculations. In the mid-1990s, I had the fortune of meeting Dr. Ulrich Knop and became a research assistant at his Institute for Medical Bionics. This was the most innovative period and significantly propelled research forward, leading to substantial progress in implementing the developed ideas and models. One of our goals was also to determine the effects of different forms of electrical currents in the body, not only to correct the erroneous descriptions that had been taught to students for decades but also to innovate new treatment possibilities. This involved not just Medium-frequency therapy but also the multifaceted low-frequency therapy, which we investigated on living subjects as well.

We found that low-frequency stimuli were only partially measurable in terms of therapeutic strength due to insufficiently effective current intensity, caused by galvanic inhibition. This was evident as superficial irritation of the skin nerves and receptors but not in the depth of the tissue in a therapeutically relevant manner. Our research goal was to identify the waveform where electrical stimuli could be measurable even at depths of three, four, or more centimeters. By applying rectangular-modulated medium frequency in bidirectional zero-line symmetrical form, we were able to scientifically prove our earlier assumptions and created models through measurements.

Medium frequency was already the topic back then, and we had the opportunity to test a development by the company Knop, alongside several other devices. Interestingly, the origins of the device were in the former Soviet Union. Based on the results we obtained, we developed further models and examined the possible range of effects - also taking into account Biophysics. We came to the conclusion that biphasic medium frequency is superior to low frequency from a physiological and neurological perspective, and has a potential that goes far beyond the previously known effects of electrical stimuli.

myostyle: The main concept that you describe in your book is Medium-frequency therapy. Could you elaborate on what it entails and what the difference is compared to low-frequency technology?

J. Winter: Biphasic medium frequency can indeed be measured deep within the body. At that time, we were also in exchange with Privatdozent Lange from the TU Dresden and Prof. Kröling from the LMU Munich. Prof. Lange, among others, found that medium-frequency currents already unfold their full effect in the sub-threshold or mildly threshold range. We were able to create various explanatory models for the body's reactions to these electrical stimuli based on biophysical aspects and medical-bionic insights, which were later confirmed. Some of the many points were: Rectangular modulated biphasic alternating current has a direct effect on the cell membrane with cluster and mosaic formations, regulates cell function, improves oxygen utilization, and leads to increased formation of cAMP (Cyclic Adenosine Monophosphate). This does not lead to a shift in neuronal potentials, acid-base balance, or pH value. Only these few mentioned effects open up completely new application possibilities.

myostyle: Medium- frequency therapy is also used for various muscular disorders, such as a lack of muscle activation. How were these investigations conducted?

J. Winter: This question pertains to the field of neurophysiology. A medium-frequency alternating current generates a nerve impulse whose discharge frequency corresponds to the natural frequency of the nerve innervating the respective muscle. It is important to note that each person has their own nerve frequency for activating each individual muscle. This is a result of their personal development and their epigenetic and genetic components. Due to the different frequencies, the muscle mass formed differs for each person as it is formed frequency-dependent. The formed muscle mass is a crucial factor for the functionality and efficiency of the muscles. An artificially generated muscle through electrostimulation, not at its natural frequency, can only be integrated into the physiological movement pattern to a limited extent and alters proprioception. However, a precise determination of the individual muscle frequency would only be possible through frequency determination via intramuscular (EMG) or neural measurement (ENG) (for each muscle individually).

Due to these individual factors, there is no standard frequency recommendation for medium-frequency therapy, as this type of current always adapts to the natural discharge of the nerve. This correlation has also been confirmed by Senn, Kröling, and Lange. The medium-frequency stimulation runs quasi-physiologically as a natural process and is not rigid/tetanic. The muscle mass formed as a result corresponds exactly to what would also be achieved through normal training. The availability of the gained muscle mass is improved, and its integration into existing movement patterns is optimized.

myostyle: The publication of the book significantly advanced the research and development of medium-frequency therapy (MET). Do you foresee future benefits for recreational sports with the development and use of medium-frequency therapy in traditional EMS systems? In your opinion, can modulated medium-frequency therapy help more people?

J. Winter: In both amateur and professional sports, medium frequency (MF) could play a significant role because it not only promotes muscle growth but also reaches the cellular level. The key term in this regard is "Beta Dispersion" - an optimal supply and disposal state of a cell achieved through MF. Beta Dispersion describes a state that all embryonic cells assume or that is adopted by cells during healing or recovery processes. Through this state, MF can also be used for "detoxification" of muscles and tissues during intense sports activities, such as in football during a congested fixture schedule. The effect would be to quickly restore muscles and tissues to a physiological balance. However, this should always occur within the framework of planned and controlled regeneration. In the area of pain management, MF can also be very effective for pain inhibition through the central nervous system, specifically the descending pain inhibition via the raphe-spinal system.

The use of MF also achieves great success in muscle building, which is not achievable with regular training alone. However, this aspect also comes with risks: With EMS, muscle mass is built quickly, but the passive musculoskeletal system is not prepared for it. Within a year, a comparatively large amount of muscle mass is built - with regular training, this muscle growth would take two to three years. Therefore, there is a faster muscle building process, but the passive musculoskeletal system, including bones, tendons, ligaments, and cartilage, does not build up in proportion during the same period. This means that although there is more strength, it meets a passive musculoskeletal system that is not adequately developed - comparable to the risky use of anabolic steroids, which can lead to damage to the connective tissue support system. If EMS training is overdone, the flow of movement also becomes less smooth, leading to changes in proprioception and, as a result, sensorimotor or biomechanical disorders.

Overstimulation over a prolonged period leads to muscle damage, which would be detectable through an increase in plasma proteinase concentration in the blood. If this condition persists over an extended period, it can lead to damage to heart valves and kidney damage - this connection was already proven in 2015. Negating or denying this fact is not acceptable, unscientific, and ethically/medically reprehensible. It concerns the health of people, and even the suspicion of possible harm must be taken into account. And this applies until proponents provide scientific/medical evidence of absolute/relative safety, as there are currently no studies with corresponding evidence. Pure assertions and assumptions are unprofessional in this case.

If MF/EMS is carried out very reasonably and with caution, it represents a great option for controlled muscle building, pain relief, and supporting recovery, allowing many people to benefit from electrical therapy.

myostyle: As a physiotherapist, you probably often advocate physical movement and activity. EMS is often seen as an alternative for people with time constraints or limited mobility who want or need to move less. Do you still think it is useful to combine EMS training with movements (mobilization)?

J. Winter: EMS training is conducted with specific movements on specialized surfaces. To create a closed chain that integrates natural movements, the following tip should be considered: Those who want to build muscles with EMS training must schedule at least eight times the duration of natural movement after the EMS session to avoid negative biomechanical/sensorimotor consequences - for example, 20 minutes of EMS training followed by equipment-free training for 160 minutes. Suitable activities include hiking in natural environments on natural terrain or ball games based on natural movement patterns. This trains intra- and extra-muscular coordination, optimizing sensorimotor skills in this newly achieved state. If equipment is preferred as a secondary option, exercises using cable machines while standing or barbell exercises are preferable.

myostyle: Can you report cases in which the use of Mid-frequency technology above 1000 Hz was helpful?

J. Winter: I have worked with extreme athletes, including those in the national team, and successfully used MF technology even during the competition phase - resulting in an active improvement in performance and a subjective decrease in physiological strain that the body must endure. The athletes emerged from competitions with a significantly different physical quality compared to athletes who did not use MF technology.

The processes described above can certainly be applied to patients suffering from muscular or trophic changes in the body. Patients experiencing pain can also benefit from MF pain treatment as a complementary therapeutic measure. Additionally, the regulatory effect on healing processes provides another opportunity for electrical stimulation applications. Recently, I have also treated patients with Multiple Sclerosis using a four-electrode application with two separate circuits during a full-body treatment. Patients report feeling fitter and overall better, leading them to use MF therapy daily.

My conclusion: Medium-frequency alternating current therapy introduces brand-new approaches, opening numerous new possibilities across various fields. These were previously unknown or were regarded as speculative until the latest scientific discoveries.

Like all good things, there is a risk of misuse with MF, so that the numerous positive effects can turn negative, which I would find very unfortunate. This is especially true when it comes to improper use in muscle building. It is recommended that such equipment should only be given into the hands of competent and properly educated professionals, considering the many possibilities that can be misused. When used in safe and in a properly managed setting, modern systems can undoubtedly be extremely helpful.

Another significant issue is the prescription of electrical applications by medical professionals. At present, prescriptions for electrical therapy in physiotherapy are almost non-existent, leading most therapists I know to offer electrical therapy to their patients, if at all, as an adjunctive treatment. I hope to see medium-frequency therapy prescribed more frequently and utilized by a greater number of therapists. They should also advocate for it loudly, highlighting the invaluable role of MF therapy as a complementary measure for managing pain and other conditions - especially since its positive benefits are well-documented.