Med Laser 2022; 11(1): 21-30
A Pilot Study to Assess the Efficacy and Safety of an Intelligent Approach to Noninvasive Body Core Strengthening with a Novel Functional Magnetic Muscle Stimulation (FMS) System
Sojung Kim
The LLAS Clinic, Seoul, Korea
Correspondence to: Sojung Kim
Received: February 19, 2022; Accepted: March 15, 2022; Published online: March 30, 2022.
© Korean Society for Laser Medicine and Surgery. All rights reserved.

This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Background and Objectives
A novel functional magnetic stimulation (FMS) body contouring device has recently been developed. The present multisite observational pilot study was designed to assess the efficacy and safety of this new FMS system for improving core strength through the strengthening of the abdominal muscle groups.
Materials and Methods
Twenty Korean subjects comprising 13 females and 7 males were recruited, with a mean age of 40.6 ± 6.67 yrs (range 33-55 yrs). All subjects received four 30-minute treatment sessions with the FMS device over two weeks, with a two-week follow-up period. At baseline and the two-week assessment point, changes in several anthropometric measurements were recorded, while ultrasound imaging assessed changes in abdominal muscle and fat thickness. A small sample of patients also underwent computerized tomographic (CT) imaging and magnetic resonance imaging (MRI) to better visualize the changes in the muscle and fat thickness and any decrease in the diastasis recti. Clinical photography was taken at baseline and at the 2-week assessment, and the satisfaction of the patients with the treatment was elicited.
All 20 subjects completed all treatments and assessments. There was no significant change in BMI or body weight at 2 weeks after the final treatment and a modest but significant decrease was seen in the waist circumference of most subjects. The large majority of the patients showed a significant increase in muscle mass accompanied by a decrease in fat thickness, which was also seen in the ultrasound imaging and corroborated by the CT and MRI findings. CT imaging revealed narrower diastasis recti. Clinical photography revealed an improved body contour combined with better posture. Patients were in general very satisfied with the treatment and the result, and no adverse events were noted by either the patients or operators during the treatment or in the follow-up period.
Overall improvement in abdominal muscle condition was achieved using the novel FMS device, with enhanced body contours and improved posture. These preliminary findings suggest that the noninvasive novel FMS system safely and effectively improved body contours and core strength.
Keywords: Functional magnetic stimulation; Intelligent electromagnetic activation; Body contouring; Core strength; Posture

In recent years the desire to maintain a healthy body has evolved in the general population combined with the additional need to “look good”, from which the field of body contouring has developed. The simplest method was adopting a high protein diet on its own which was more effective combined with exercise; but the modern (and often younger) patient has moved away from the “no pain-no gain” philosophy of gym- or fitness center-based workout body training towards the “all gain with minimal pain” approach and has started demanding an easier noninvasive way to achieve their new “body beautiful”.

At first, the approach involved removing or “melting” fat, and body contouring evolved with a number of fat-targeting modalities including mechanical liposuction, laser lipolysis, laser-assisted liposuction, targeted or high-intensity focused ultrasound (HIFU), cryolipolysis and radiofrequency.1-8 Varying degrees of efficacy were achieved which were very much operator- or device -dependent, but there was also the possibility of unwanted side effects, such as panniculitis or transient nerve damage, and in the case of mechanical liposuction, death.9,10 Apart from these problems, in some cases hyperplasia would occur as the freed lipocytes would migrate to other sites on the body, or rebound at the treatment site giving a “yo-yo” effect because in most cases only the fat was being targeted with no consideration given to adjacent muscular tissue or overlying skin.

Muscle activation depends very simply on electricity. Motor nerves which control muscular activity connect to their muscle fibers at neurovascular junctions, a highly specialized synapse which translates electrical impulses from the nerve into muscle contractions.11 Based on this mechanism, systems were developed which could target specific muscles to induce or stimulate involuntary muscle contraction, thereby providing the equivalent of exercise-based training. By and large, devices fell into two categories: electromuscular stimulation (EMS) and functional magnetic stimulation (FMS).12-14 As their names suggested, EMS depended on direct electrical stimulation of the muscle neurovascular junctions via electrodes placed on the skin over the target muscles, whereas FMS worked via a magnetic field generated from an applicator containing a coil through which an electric current was passed: the magnetic field in turn induced an active potential at the neurovascular junction (Faraday’s law of induction)15 to stimulate the desired muscle contractions.

The history of EMS is considerably longer than that of FMS, dating back to the Victorian fascination with ‘Galvanism’,16 since it was much simpler to place electrodes directly on the skin to deliver an electrical current to the underlying muscle group than it was to develop the necessary technology to design an efficient coil-based applicator capable of producing a strong enough magnetic field to stimulate the target muscles in a noncontact manner. Technology however triumphed. Articles demonstrating how magnetic energy could rehabilitate damaged muscles first in animal models and then in human subjects began to appear from around the end of the first decade of the New Millennium based on earlier reports from the 1980s of the use of magnetic stimulation to target the human motor cortex.17-19 However, more germane to muscle mass training, a surge of articles has appeared in the last few years on the successful indication of what has now been termed ‘high intensity focused electromagnetic technology’, under the acronym HIFEM. Indications first included therapeutic targets, such as strengthening the muscles of the pelvic floor to alleviate stress urinary incontinence, but gradually moved towards more aesthetic goals such as toning and shaping the abdominal muscles, strengthening the core, lifting the buttocks and sculpting thighs and arms.18,20-25

As already noted, EMS depends on passing an electric current through the skin from the electrodes to reach the target muscle, and as skin is a conductor with some degree of resistivity (impedance) , passing current through such a conductor generates heat. This presents a limitation for EMS regarding the strength of the current. The stronger the current, the more powerful the muscle contraction and the better the toning effect: on the other hand, the stronger the current, the greater the amount of electrothermal energy, or heat, produced in the conductor. This can eventually cause discomfort and pain, generated in the skin. FMS has no such limitation as the magnetic field passes through the skin without affecting it at all and is directly absorbed by the target neuromuscular junctions. There are two other limitations to FMS. First of all, muscles are affected en bloc and it is difficult to achieve specific muscle movements. Secondly, and this is also a potential problem with EMS, the stronger the muscle contraction, the more efficient is the toning but there is a muscle contraction threshold which varies from patient to patient beyond which patients can find the stimulation extremely uncomfortable, to the point of wanting the treatment stopped.

The new CoreLevéeTM system, (Lutronic, Goyang, South Korea) has overcome both these problems through the incorporation of a proprietary Intelligent Electromagnetic Activation (iEMA) Technology into the system and applicators. The applicators generate powerful fluctuating magnetic fields capable of generating thousands of involuntary muscle contractions and relaxation in the recommended 30 minute treatment period, thereby building the ideal body shape. The repetitive contraction and relaxation of the muscles is transmitted to adjacent adipose tissue, raising the basic metabolic rate of the fat cells and inducing adipocyte apoptosis both through physical manipulation and creation of heat through kinetic energy.26 This reaction has the potential to reduce the thickness of the fat layers while increasing the thickness of the target muscles. This repetitive oscillating vibratory motion is further transmitted to the overlying skin, encouraging fibroblast activation leading to skin remodeling and tightening.27 Another reported benefit from FMS has been published regarding increasing the percentage of slow-twitch muscle fibers in targeted muscles.17 Slow-twitch muscle fibers are associated with endurance, are fatigue resistant, and play a very important part in postural control and maintaining the body core.28

A treatment regimen with this novel FMS system thus could not only strengthen muscles but also develop body contour with no yo-yo effect, help improve posture and potentially enhance skin aesthetics. The present multisite observational pilot study was therefore designed to assess the efficacy and safety of the new system for improving body contour, core tone and posture through strengthening the abdominal muscle groups.


Twenty Korean subjects were recruited to be treated either in the in-house clinic or a geographically distant site, comprising 13 females (65.0%) and 7 males (35.0%), with a mean age of 40.6 ± 6.67 yr (range 33-55 yr). Demographic data are shown in Table 1. (Raw demographics data in Supplementary Table 1) During the treatment and follow-up periods, subjects were asked to continue with their normal activities of daily living (ADL) regarding alcohol consumption, dieting or whatever form of work-out they might be following.

Table 1 . Baseline patient demographics

Male7 (35%)
Female13 (65%)
Age (yr)
≥ 502
Mean ± SD40.6 ± 6.67
Waist Circumference (cm)
< 701
≥ 901
Body weight (kg)
< 501
< 18.5 (Low BMI)1
18.5-24.9 (normal)14
25.0-29.9 (Overweight)5
Drink alcohol14

All subjects were treated with the CoreLevée system as shown in Fig. 1, consisting of the system console and two applicators. System control is managed via a touch-screen graphic user interface (GUI) from which treatment parameters can be selected including the individual treatment programs which deliver selected muscle activation modes over a chosen treatment time, and variable treatment levels. The strength of the delivered magnetic fields varied depending on the selected program, but the maximum field strength was 2.5 T. The selected muscle activation modes were delivered at frequencies varying from zero hertz for the static programs to a maximum of 150 Hz for the dynamic programs.

Figure 1. The Lutronic CoreLevéeTM system as used in the present study, showing the console and the GUI at the top, with the applicators attached via their umbilical cords.

The magnetic fields generated by the system applicators penetrates deeply into the target muscle groups enabling effective treatment even in obese patients. Each subject received four 30-minute treatment sessions over two weeks, with a two-week follow-up period. This optimized regimen was arrived at after a series of preliminary sessions varying in length and frequency (data not shown). Areas which can be treated are the abdomen, the buttocks and the thighs but in the present study the target muscles consisted of the abdominal group. During each treatment a single applicator was applied to the abdomen centered over the umbilicus and firmly held in place with a dedicated belt, as illustrated in Fig. 2. For the present study, the system was set to the Auto Mode, which consisted of four sequential individual muscle activation modes in the order as follows:

Figure 2. Illustration showing the applicator being placed on the abdomen and secured with the dedicated belt.

• Relaxing ‘Tap’: this is a static treatment designed for warming up before active muscle stimulation. It relieves tension and fatigue by stimulating muscles under stress from normal daily activities. It makes the patient feel as if they were getting a massage.

• Contracting ‘Hold’: this is a dynamic treatment delivering isotonic contractions which are designed to stimulate both slow-twitch (ST) and fast-twitch (FT) muscle fibers by magnetic fields ranging from low to high intensity.

• Relaxing ‘Crunch’: both static and dynamic actions are incorporated in this setting, and it aims at allowing a period of muscle recovery after the dynamic Hold session. It is however a quasi-rest action, in which short alternating periods of relaxation and contraction are induced in the muscles in static and dynamic modes.

• For the final level in the Auto Mode, full-strength ‘Squeeze’: this is a highly dynamic mode that delivers strong and continuous stimulation so that even the deeper layers of muscle can be stimulated evenly and maximally, delivering a full muscle work-out to all abdominal muscles.

Bearing in mind that each patient will have a discomfort threshold beyond which muscle contractions may well be painful, the system is equipped with a hand-held patient comfort switch that subjects could activate to stop treatment immediately if the muscle contractions caused too much discomfort.

As for assessments, during and between treatments and at the 2-week follow-up patients rated their comfort, and any adverse events were noted. Patients were additionally asked about their satisfaction with the result at the 2-week assessment. Abdominal clinical photography was taken at baseline and at the 2-week assessment (iPhone 12 max Pro 12 megapixel camera under identical distance and lighting conditions, full face and profile: F-stop, F/1.6; Exposure time,1/120 s, ISO, 64-80; focal length, 5 mm ).

At baseline and at the two-week assessment point, changes in a number of anthropometric measurements were recorded (BMI, body weight, muscle mass, body fat as a percentage of body weight and waist circumference). Whole-body measurements were obtained based on bioelectrical impedance analysis (BIA) with the InBody 230 system (InBody Co., Ltd, Seoul, South Korea), while waist circumference was measured at the level of the umbilicus keeping the measuring tape horizontal and snug around the waist, but not compressing the skin. At the same assessment points, ultrasound imaging was employed to assess changes in abdominal muscle and fat thickness (ML6-15 system from the General Electric LOGIQTM E10 series). A very small sample of patients also underwent computer tomographic (CT) imaging (iCT SPTM scalable platform from Phillips Healthcare) and magnetic resonance imaging (MRI, IngeniaTM 1.5T CX also from Phillips Healthcare) to better visualize changes in muscle and fat thickness and any decrease in the diastasis recti, decrease of the latter indicating tightening and flattening of the abdomen. Changes in anthropometric values were expressed as a percentage of the baseline value, while all data at baseline and follow-up were expressed as means plus or minus standard deviation (SD) and were examined for statistical significance (2-tailed paired t-test, SPSS Software Ver 28, IBM UK).

Having had the treatment protocol fully explained to them, including potential results and side effects, together with assurance that all data were depersonalized, all subjects provided written informed consent to participate in the study and for use of their clinical photography. The protocol design was approved by the in-house Safety Committee, and the study was performed following the precepts of the World Medical Organization Declaration of Helsinki (2000).


All 20 subjects completed all treatment sessions and the baseline and follow-up assessments. No subject used the patient comfort switch during treatment. There was no significant change either way in BMI or body weight at 2 weeks after the final treatment. The mean BMI at baseline was 22.55 ± 2.56 and at the follow-up assessment it was 22.530 ± 2.54. Two patients showed no percentage change in their BMI, 11 patients showed a modest percentage decrease from 0.1%-4.0% (mean 1.83 ± 1.07%), 2 patients remained the same and 7 patients showed a modest increase from 0.4%-1.1% (mean 0.76 ± 0.27%). Mean body weight at baseline and 4-week assessment was 61.240±10.596 kg vs 60.855±10.678 kg, with 11 patients showing a modest percentage decrease in body weight ranging from 0.3% to 4.0% (mean 1.6 ± 1.14%), 1 patient remaining at the same weight and 8 patients showing a modest percentage increase from 0.2% to 1.2% (mean 0.6 ± 0.32%).

The mean muscle mass at baseline was 24.5 ± 6.1 kg (19.0 kg-36.4 kg) and at the 4-week assessment was significantly reduced (p < 0.001) at 25.0 ± 6.2 kg (19.3 kg-37.8 kg). The large majority of the patients (17/20, 85%) showed a significant increase in their muscle mass. The data for body fat expressed as a percentage of body weight showed overall a significant decrease (17/20 patients, p < 0.001), with a mean value at baseline of 26.5 ± 5.5%, (range 16.0%-34.0%) and 24.9 ± 5.3% at the 2-week follow-up (range of 15.3%-32.9%). The mean percentage change at the 2-week follow-up compared to base line was 8.8 ± 5.2%, ranging from 1.2%-18.2%. As for waist circumference (Table 1), a modest but significant decrease was seen in the majority of subjects (16/20, 80%) (mean 80.5 ± 5.9 cm at baseline, range 70.3 cm-91.2 cm); mean at the 2-week assessment, 78.4 ± 6.1 cm, range 68.7 cm – 87.3 cm, p < 0.001 for all) (Raw data on muscle mass and body fat expressed as a percentage of body weight can be seen in Supplementary Table 2).

Relative to baseline values, Table 2 summarizes the mean percentage increase in muscle thickness as assessed with ultrasound imaging at 2 weeks after the fourth and final treatment compared with baseline values, which was 17.51 ± 10.01% (range 2.6%-38.8%), while the percentage decrease in fat thickness was 12.67 ± 10.88% (range 0.7%-39.4%), with high statistical significance for the respective increase and decrease in muscle and fat thickness (p < 0.001 for both) (Raw data in Supplementary Table 3).

Table 2 . Changes in muscle and fat thickness and diastasis recti compared between baseline and follow-up assessment 2 weeks post final treatment

Item measured (mm)B/LF/U% change from B/L
Muscle thickness1.15 ± 0.261.54 ± 0.21+17.76 ± 9.69%**
Fat thickness1.59 ± 0.681.38 ± 3.65?13.17 ±10.22%**
Abdominal Separation (Diastasis recti)2.1 ± 0.701.86 ± 0.65?11.6 ± 3.34%*

B/L, Baseline; F/U, 2-week follow-up.

Measured with ultrasound; Measured with computed tomo­graphy.

*p = 0.01; **p = 0.0001.

No adverse events were noted by either the subjects or clinician during and between treatment or the 2-week follow-up. Mild to moderate discomfort was reported, but no patient found the procedure so uncomfortable that they needed to activate the patient comfort switch to halt the treatment. All patients expressed satisfaction with the results, and would be willing to have another treatment if any top-up was required.

As for representative clinical illustrations, Fig. 3A, B shows representative MRI findings of Patient 18, a 40-year-old female, at baseline (3A) and at 2 weeks after the final treatment session (3B). The muscle thickness had increased by 10.3% whereas the fat thickness had decreased by 29.2%. The diastasis recti distance had decreased by 15.1% (based on CT imaging not shown). Fig. 3C, D shows the abdominal clinical photography at baseline (3C) and at the 2-week assessment (3D) showing a clear improvement in abdominal protrusion, and a straighter posture. Representative computed tomographic images are shown of a 33-year-old male (Patient 20) at baseline (Fig. 4A) and 2 weeks after the final treatment (Fig. 4B). Muscle thickness had increased by 21.3% whereas subcutaneous fat had decreased by 17.8%. The diastasis recti was 15.3% narrower. These findings were corroborated by the improvement in abdominal contour and spinal posture in the clinical abdominal photography seen 2 weeks after the final treatment in Fig. 4D compared with baseline (Fig. 4C) (Raw CT and MRI data in Supplementary Table 4).

Figure 3. Magnetic Resonance Images and Abdominal clinical photographs of Subject 18 before (A) and 2 weeks after last treatment (B). Female (40), BMI 19.9 kg/m2 (before) and 19.2 kg/m2 (2 weeks), weight –2.1 kg (–4.0%), subcutaneous fat –29.2%, muscle thickness +10.3%, diastasis recti –15.1%. (subcutaneous fat and muscle thicknesses are based on MRI data, and diastasis recti is based on CT data).
Figure 4. Computed Tomography and abdominal clinical photographs of Patient 20 before (left) and 2 weeks after last treatment (right). Male (33), BMI 25.1 kg/m2 (before) and 24.7 kg/m2 (2 weeks), weight –1.1kg (–1.4%), subcutaneous fat –17.8%, muscle thickness +21.3%, diastasis recti –15.3%.

Although the CT sample size was small, improvement was seen in the volume of visceral fat at baseline and at the 2-week assessment after treatment with the novel FMS system (representative images from Patients 18 and 20 in Figs. 5 and 6). A larger patient population would allow this particularly interesting finding of reduction in visceral fat to be confirmed.

Figure 5. Visceral fat cross-sectional area on computed tomography imaging of Patient 18 (same patient as in Fig. 3) before (A) and 2 weeks after last treatment (B). Visceral fat cross-sectional area has decreased by 2.1%.
Figure 6. Visceral fat cross-sectional area on computed tomography imaging of Patient 20 (same patient as in Fig. 4) before (A) and 2 weeks after last treatment (B). Visceral fat cross-sectional area has decreased by 15.1%.

With the heightened importance of physical fitness among the general population, there has been a rise in the desire for a variety of contouring products to acquire a toned physique with a particularly fast-growing demand for noninvasive approaches. Taken together with the increasingly powerful dynamic force of social media, the awareness of millennials in particular regarding their physical appearance is increasing, thereby driving the demand for body contouring procedures. Focus has shifted away from getting rid of fat towards developing a more aesthetically-pleasing sculpted and toned body through muscle training. In any case, merely getting rid of fat in many cases did not achieve a long-term improvement as a paradoxical increase in fat deposits in other parts of the body occurred through migration of freed adipocytes, or the fat in the treated area might return, creating the yo-yo effect leading to despair among many dieters. There is also a trend away from traditional gym-based or fitness center-based body training towards non-invasive approaches, probably driven by the extremely busy lifestyle of the professional millennial. The two main non-invasive approaches have become electromuscular stimulation (EMS) and functional magnetic stimulation (FMS). Both of these techniques depend on non-invasively inducing repetitive involuntary contraction and relaxation of the targeted muscle groups, thereby replacing weight training and other fitness centre methods for developing muscle power and tone.

EMS must transmit its electrical energy through the skin to reach the target muscles, and as the skin is a conductor with a certain resistance, the higher the current the hotter the skin will get as the current meets the resistance. This obviously has negative connotations as far as maximizing muscular activation as a low patient pain threshold will give submaximal activation. No such obstacle exists with FMS. Powerful magnetic fields can pass through skin without affecting it in any way, and all the incident energy specifically targets the neuromuscular junctions between the motor nerves and the muscle fibers they control to deliver the maximum optimal contractile force. This ensures the best possible noninvasive workout for the muscles, helping develop fiber hypertrophy. Histological studies in a porcine model have clearly demonstrated the efficacy of FMS in noninvasively increasing muscle fiber hypertrophy and hyperplasia,29 and increased muscle thickness has been linked to increased muscle strength and tone and correlated with strength training-induced hypertrophy.30 In the present study, the ultrasound findings clearly suggested a significant increase in abdominal muscle thickness in all subjects at 2 weeks after the final treatment session, which was backed up by the small sample of subjects examined with CT and MRI. This was complemented by a decreased fat thickness. It has been suggested that the athermal induction of repetitive tightening and relaxation of the abdominal muscles alternately compresses and releases the adjacent fatty tissue, transferring energy to the adipocytes and inducing apoptosis.26 This reaction is probably enhanced by mild heating of the adipocytes by kinetic energy released by the constant muscle-mediated ‘squeeze and release’ effect transmitted by the action of the FMS system used in the present study on the abdominal musculature.

Some of the subjects reported they were on a diet (9/20) and others were performing some form of workout (10/20) although details of diets or workout regimens were not elicited or monitored: of these, 6 subjects were both dieting and working out. Interestingly, the effect of the FMS treatment on these subjects did not appear to be significantly better compared with those subjects who were neither working out nor dieting although a formal analysis of these data was not completed. In addition to the body measurement and US data showing thicker muscles with greater muscle mass and thinner fat with decreased mass, the limited CT sample also demonstrated a narrower diastasis recti suggestive of flattening or tightening of the abdomen, but the numbers were too small to come to a solid conclusion and further study with a larger patient population is warranted to prove this beneficial effect. However, the clinical photography has borne this tightening effect out (Figs. 2-5). The photography also demonstrated how the posture of the patients had been improved, the consequence of a better-developed core with potentially a higher ratio of slow-twitch to fast-twitch muscle fibers which will help sustain posture better over longer periods.17

One problem seen with FMS is its fairly nonspecific action on the entire target muscle mass without any modulation of the rhythm or direction of the muscle contraction. The intelligent electromagnetic activation (iEMA) technology built-in to this novel FMS system coupled with a propietary electrode redesign has eliminated this problem, and the four specific actions of Tap, Hold, Crunch and Squeeze are designed to impart specific exercise patterns on the target muscles, namely the abdominal group in the present study. These actions were applied in the Auto Mode which exercises the muscles in that static, dynamic, static and dynamic and fully dynamic sequence thereby delivering a complete work-out. These four actions can be selected individually or combined in a tailored program to give a truly targeted workout for individual patients based on their needs and body type, and the strength of the muscle workout is also fully adjustable to deliver a customized noninvasive muscle training program. It should be noted that, although the target in the present study was the abdominal muscle group, the system applicators can also be used effectively on the thighs and buttocks.

The regimen in the current study consisted of four 30-minute sessions delivered over a two-week period, arrived at after a series of experimental sessions of varying lengths and intervals. Fifteen, 20, 30, and 45 minutes were trialed for the length of each session. The Auto program was selected as the optimum standard choice because it combined both static and dynamic actions. Accordingly, the best length was 30 minutes, and was also thought to be a reasonable treatment time for patient convenience. The next consideration was the number of sessions. The effect of the treatment sessions is cumulative. Four sessions appeared as an ideal number, with fewer sessions not producing enough cumulative effect, and more sessions potentially putting a burden on patients regarding time. Once again for patient convenience it was felt that two sessions a week was ideal, separated by three days to allow time for recovery after each session, but not too much time so that the cumulative effect could be maintained. The final regimen was therefore sessions on, for example, Monday and Thursday or Tuesday and Friday with a two-week period. The patients found this arrangement was workable and balanced repeated sessions with inter-session recovery time. This regimen is therefore the recommended standardized approach, but more sessions can be added with a different mode for each session depending on the individual patient’s requirements.

All subjects expressed satisfaction with their results although a formal patient satisfaction questionnaire was not included in the study assessments. Furthermore, the subjects would all be willing to have further treatment sessions with this FMS device. Strong muscle contraction-related discomfort was reported as moderate but bearable, and subjects stated that it tended to become more bearable as they acclimatized to it with time and repeated sessions. Regarding the safety of the system and treatment, although subjects reported some muscular discomfort during the treatment, it never caused any subject to stop treatment or refuse subsequent treatments, and ceased completely as soon as the magnetic field was released with no residual lactic acidosis as might be the case after a conventional workout session with weight training. There was little if any residual erythema in the skin under the applicator, and what little there was resolved within minutes. This was due to the ability of the FMS magnetic field to pass straight through the skin overlying the target musculature without affecting it in any way, compared with the potential for the heat-related effects, including pain, associated with skin electrical resistivity which can occur with EMS systems. Indeed, through the mechanical stimulation of the skin transmitted via the rhythmic contractions of the target muscles, some skin tightening benefits were observed to accrue. As for any electrical hazard, there was none other than those associated with any device operating on mains electricity and preventable by simple common sense.

The present observational pilot study has some limitations. The subjects were all volunteers, and therefore not a true cross-sectional representation of the general population and it was an observational uncontrolled study. The allocation of subjects to the two treatment sites was not formally randomized. The follow-up at 2 weeks was too short to judge the long-term effect of the present FMS treatment regimen. In subsequent studies much longer follow-up assessments are required, but the 2 weeks was enough to give an idea of the efficacy. It could well be that the effect might increase with a longer period between the final treatment and assessment, and this needs to be examined. No attempt was made to monitor the efficacy specifically in those subjects who were dieting, working out or both, compared to others who were not and this could have had the potential to skew the results (although the efficacy appeared to be more or less the same among those groups). That should be addressed in a future study with a proper statistical subgroup analysis. Finally, the more objective CT and MRI sample was very small, owing to the somewhat prohibitive cost of these procedures for what was only a pilot study, but did still confirm thicker musculature and thinner fat. Of special interest would be a statistical analysis of the effect of the system used in the present study on visceral fat in future studies.

The above limitations aside, this was intended only as an observational pilot study, and the body measurement data and ultrasonography findings strongly suggested the efficacy and safety of intelligent electromagnetic activation (iEMA) for noninvasive body contouring with this novel FMS system, showing an overall increase in muscle thickness combined with a decrease in fat thickness, leading to a flatter abdomen, better muscle tone and improved posture. Further studies with larger populations are warranted to confirm the optimistic results of the present study.


The author is grateful to Dr. R Glen Calderhead for his help with the English of the article and Dr. Heejin Park (Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea) for his help with the CT and MRI examinations and reading the images.


No potential conflict of interest relevant to this article was reported.



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