JD McCoy, NMD^1*, Jonathan Schoeff, MD, FACS², Richard Goldfarb MD, FACS³

¹Contour Medical, Gilbert, AZ, USA

²The Longevity Lab, Greenwood Village, CO, USA

³Richard Goldfarb MD, FACS, Downingtown, PA, USA

^*Corresponding author: JD McCoy, NMD, Contour Medical, 633 E Ray Rd STE 103, Gilbert, AZ 85296, USA.

Received: 02 July 2025; Accepted: 10 July 2025; Published: 08 August 2025

Article Information

Citation: JD McCoy, Jonathan Schoeff, Richard Goldfarb. Preserving Muscle Mass During GLP- 1RA Induced Weight Loss Using Combined HIFEM and Synchronized Radiofrequency Technology. Archives of Clinical and Biomedical Research. 9 (2025): 316-321.

DOI: 10.26502/acbr.50170468

Abstract

Keywords

GLP-1RA; HIFEM; Muscle; Weight loss

Article Details

1. Introduction

Glucagon-like peptide-1 receptor agonists (GLP-1RAs), originally developed to treat type 2 diabetes, are now widely prescribed for weight loss and represent a promising therapeutic option for obesity management [1]. Notable drug examples in this class include exenatide, liraglutide, dulaglutide, and semaglutide [2].

GLP-1RAs mimic the GLP-1 peptide hormone that is produced by intestinal enteroendocrine L-cells and certain neurons in response to food intake. GLP-1RAs contribute to weight loss through several mechanisms [1]. They delay gastric emptying, which enhances satiety, and act on GLP-1 receptors in the hypothalamus, a food intake regulation brain area, to suppress hunger, reduce food cravings, and improve eating behaviors [1,3-6]. Clinical trials consistently show that GLP-1RAs can reduce weight between 5% and 10% of total body weight in obese patients [1,3].

While weight loss can significantly improve health outcomes in overweight and obese individuals, rapid weight reduction often leads to the unintended loss of lean body mass (LBM), particularly skeletal muscle mass (MM). A review of studies involving 1,641 adults on semaglutide reported that up to 40% of weight loss was from MM [7]. Skeletal muscle is not only essential for movement but also serves as the body’s largest insulin-sensitive tissue, accounting for about 80% of postprandial glucose uptake [8]. It also plays a role in lipid metabolism and is a key determinant of basal metabolic rate (BMR) [9,10]. Loss of muscle mass can reduce BMR, therefore make long-term weight maintenance more challenging, and increasing the risk of type 2 diabetes [10,11].

Preserving MM during weight loss may be achievable through strength training and a protein-rich diet [12-14]. However, during substantial weight loss, individuals may experience a decline in energy levels, which is confirmed by prior studies showing reduced amounts of physical activity in participants undergoing a weight loss program [15,16].

In addition, the time and effort required for consistent resistance training may not be feasible for many individuals. Moreover, due to appetite suppression and prolonged satiety caused by GLP-1RA treatment, patients may find it difficult to attain their sufficient daily protein intake of 1.2-2g/kg to preserve their MM [17,18].

To address these challenges, non-invasive technologies have emerged as supportive tools in body contouring. One such method is the concurrent use of HIFEM and synchronized radiofrequency (RF) technology. This combination therapy targets fat reduction and muscle growth simultaneously and has been validated in aesthetic medicine for body sculpting in areas such as the abdomen, buttocks, arms, and thighs [19-22]. HIFEM induces supramaximal muscle contractions that exceed voluntary exercise capacity, stimulating hypertrophy and hyperplasia through satellite cell activation and expression of heat-shock proteins [23-25]. Meanwhile, the RF component selectively heats tissue based on electrical impedance, triggering fat cell apoptosis at temperatures between 107.6°F and 113° [26,27]. Meanwhile, in the muscle tissue, the RF heating reaches a safe 104°F, and in synergy with the HIFEM procedure, RF recruits myosatellite cells, promoting muscle regeneration and further strengthening [23].

This retrospective study aims to investigate the effects of combined HIFEM and RF technology on preserving skeletal muscle mass during GLP-1RA weight loss treatment.

2. Materials and Methods

2.1 Participants

This retrospective cohort study utilized data from the existing clinical database containing records from patients who underwent weight loss interventions between 2022 and 2024. Data on age, sex, height, and change in body weight and composition of participants were obtained from the database. Participants were eligible for inclusion if they met the following criteria: (1) aged 21 years or older, (2) had a baseline body mass index (BMI) of ≥18.5 kg/m², (3) received either glucagon-like peptide-1 receptor agonist (GLP-1RA) therapy, HIFEM combined with synchronized radiofrequency (HIFEM+RF) treatment, or both concurrently, and (4) had at least one follow-up bioelectrical impedance analysis (BIA) beyond the baseline assessment. Patients who met the eligibility criteria were contacted via email or telephone, informed about the study's objectives, and provided written informed consent for the use of their data in this analysis.

Participants were divided into three cohorts: group G received only GLP-1RA treatment for weight loss, group GHR received GLP-1RA treatment concurrently with HIFEM+RF treatment, and group HR received only HIFEM+RF treatment. Group HR served as a control group.

2.2 Bioelectrical impedance analysis (BIA)

Body composition was assessed using multi-frequency bioelectrical impedance analysis (BIA) via the InBody system (InBody Co., Ltd., Seoul, Republic of Korea), a widely used tool for non-invasive estimation of body fat (FM) and muscle mass (MM). BIA measures impedance to a low-level electrical current that passes through the body, with the resistance varying based on tissue composition. As muscle tissue contains a higher water content than adipose tissue, it presents lower impedance, enabling estimation of muscle mass, fat mass, and total body water [28].

BIA assessments were conducted under standardized conditions. Participants were instructed to void their bladder and avoid food and exercise for at least three hours prior to measurement. During the scan, subjects stood upright with bare feet and placed their thumbs and heels on the designated electrodes.

Body weight and body composition (fat mass and skeletal muscle mass) were recorded during each BIA session. BMI was calculated using the formula: BMI = weight in pounds / height in inches² × 703. For each participant, the changes in weight, BMI, fat mass, and skeletal muscle mass were computed as the difference between baseline and the most recent follow-up measurement. Group-level means and standard deviations were then calculated to assess average changes within each cohort.

2.3 Statistical analysis

Descriptive statistics, including means and standard deviations, were calculated to summarize baseline characteristics and outcome variables. Group comparisons for changes in body weight, BMI, fat mass, and muscle mass were conducted using the Kruskal–Wallis test. Where significant overall differences were detected, post hoc pairwise comparisons were performed using Dunn’s test. Statistical significance was set at a p-value of < 0.05.

3. Results

A total of 63 participants were enrolled and evenly distributed across three treatment groups: group HR (n=21, 7 males, 14 females, 50.8±11.3 years); group G (n=21, 2 males, 19 females, 48.3±21.0 years), and group GHR (n=21, 6 males, 15 females, 46.0±13.1 years).

3.1 Baseline weight and body composition

At baseline, participants in group G had an average body weight of 161.8±29.9 lbs and a BMI of 26.8±3.3 kg/m². Their mean fat mass was 55.3±17.0 lbs, corresponding to a body fat percentage of 33.9±7.9%. Their muscle mass averaged 58.9±13.5 lbs, or 36.5±4.7% of total body weight.

Group HR showed a similar average weight of 161.5±30.2 lbs, but with a lower BMI of 24.6±3.4 kg/m². Their fat mass was 39.9±14.4 lbs (25.0±8.1% body fat), while muscle mass was higher at 67.9±17.3 lbs, making it 41.8±5.0% of body weight.

In group GHR, the baseline mean weight was 157.0±35.2 lbs with a BMI of 25.9±3.3 kg/m². Fat mass averaged 44.2±15.4 lbs, accounting for 28.8±9.6% body fat, and muscle mass was 68.1±22.7 lbs, or 42.8±10.3% of body weight. Full baseline data are presented in Table 1.

Statistical analysis revealed differences were only in baseline fat mass weight (p = 0.01) between groups G and HR; no other significant differences between groups were in baseline values (p > 0.05).

Table 1: Age, body weight, BMI and body composition of the study cohorts at baseline, expressed in mean±SD.

3.2 Weight and BMI Changes

Among the groups, group G lost the most amount of body weight, with an average reduction of 14.7±8.7 lbs. Group GHR experienced a more moderate weight loss of 7.1±11.7 lbs, while group HR showed a slight gain in body weight, averaging 1.2±6.2 lb. Corresponding changes in BMI mirrored this pattern: group G demonstrated a reduction of 2.5±1.5 kg/m², followed by a 1.3±2.0 kg/m² decrease in group GHR, and a reduction of 0.2±0.9 kg/m² in group HR, despite an observed weight gain. Statistical comparisons revealed significant differences in weight and BMI changes between groups G and HR (p < 0.001) and between groups HR and GHR (p = 0.007). The difference between groups G and GHR was not statistically significant (p = 0.176).

3.3 Body Composition Changes

Fat loss by weight was on average 10.2±8.3 lbs in group G, 8.1±9.4 lbs in group GHR, and 1.7±5.6 lbs in group HR. In terms of body fat percentage, group G decreased by 3.5±4.3%, group GHR by 3.9±4.3%, and group HR by 1.1±2.6%.

Statistical analysis revealed significant differences in fat weight change between groups G and HR (p < 0.001), and between groups HR and GHR (p = 0.007). No significant difference was observed between groups G and GHR (p = 0.176).

Group G experienced a decrease in muscle mass, averaging 2.9±1.3 lbs (19.4% of total body weight loss). Conversely, group GHR gained 1.0±3.1 lbs, and group HR gained 1.8±3.1 lbs. Despite these differences in absolute muscle mass, body muscle percentage increased across all groups. Group HR showed an average increase of 0.7±1.6%, group G by 1.6±2.3%, and group GHR increased by 3.3±3.1%.

Changes in muscle weight differed significantly between groups G and HR (p< 0.001), as well as G and GHR (p< 0.001). No significant difference was observed between groups HR and GHR (p > 0.999). For body muscle percentage, significant differences (p = 0.006) were found as well. Full post-treatment data and change data can be found in Tables 2 and 3, respectively.

Table 2: Post-treatment body weight, BMI and body composition of the study cohorts expressed in mean±SD.

Table 3: Changes in body weight, BMI and body composition of the study cohorts from baseline to post-treatment, expressed in mean±SD.

4. Discussion

This study investigated the efficacy of combining HIFEM and Radiofrequency treatments (HIFEM+RF) in preserving muscle mass (MM) during pharmacologically induced weight loss using GLP-1 receptor agonists (GLP-1RA). The findings suggest that the HIFEM+RF intervention mitigates the loss of MM associated with rapid weight reduction and may actively promote muscle gain.

Participants who received HIFEM+RF treatments (Group GHR) experienced an average of 1.0 lbs increase in muscle mass, in contrast to the 2.9 lbs decrease in MM observed in the group receiving only GLP-1RA therapy (Group G), corresponding to a difference of 3.9 lbs in muscle mass between the groups. An increase of 1.0 lb of muscle mass is equivalent to approximately eight weeks of regular resistance training in individuals not undergoing a weight loss program [29]. However, as discussed above, maintaining muscle mass during weight loss is highly challenging [12]. In such conditions, exercise generally serves to reduce muscle loss rather than promote muscle gain [30,31], making the observed muscle increase in this study notably distinct. Importantly, both groups lost a comparable amount of fat mass, as measured by body fat percentage, but only group G exhibited a loss in MM. The difference in muscle mass change between these groups was statistically significant (p < 0.001).

Although Group G lost more total weight and showed a greater reduction in BMI compared to Group GHR, this additional weight loss is largely attributable to a loss of muscle mass, which accounted for 19.4% of total body weight lost. This finding is in alignment with prior research describing significant amounts of muscle loss during GLP-1RA weight loss programs [7].

When adjusted for body composition, the HIFEM+RF group achieved a more favorable outcome: a simultaneous reduction in fat mass and increase in muscle mass, indicating an overall improvement in body composition rather than simple weight loss. This is evident when comparing post-treatment metrics. Despite group G and GHR reaching similar weight and BMI, group G had higher body fat (group G 30.4% vs. group GHR 24.9%) and lower muscle mass (group G 38.1% vs. group GHR 46.2%) compared to group GHR.

Similarly to group GHR, the control group receiving solely HIFEM+RF treatments (group HR) showed the procedure was effective in improving body composition, demonstrating body fat reductions (-1.7 lbs) and MM increase (1.8 lbs). However, mean weight increase was observed due to MM gain.

These findings suggest the non-invasive HIFEM+RF procedures as a beneficial adjunct therapy to pharmacological weight loss programs for the preservation of muscle mass. Moreover, the procedures offer selective fat reductions and muscle enhancement, which is not possible with weight loss or exercise [32]. Furthermore, the treatment requires minimal effort from patients, making it a practical and accessible option, especially during weight loss, when reduced energy levels often make regular exercise difficult to sustain [15,16]. As discussed above, maintaining or improving MM is crucial not only for daily physical functioning, but also for our metabolic health, longevity and maintaining weight loss [10,11].

Although the study findings are promising, several limitations must be considered. Dosage and the duration of the GLP-1RA treatments, nor the HIFEM+RF treatment numbers and area, or therapy intensity, was assessed, as this information was not obtained. Secondly, the sample size was relatively small, which limits the generalizability of the results. Further research would benefit from including a larger sample size, investigating the role of weight loss duration and speed, as well as GLP-1RA dosage, number, intensity and treatment areas of HIFEM+RF procedures.

Despite limitations, the study had notable strengths. Firstly, body composition was objectively analyzed using the BIA system, a widely used method for assessing body composition. The study compared three groups, which allowed for comparative analysis of changes in body composition among pharmacological, device-based, and combination treatment approaches. Lastly, the study sample included a wide range of age and BMI, allowing for a greater generalizability of the results.

5. Conclusions

The results of this study indicate that combining HIFEM+RF procedures with GLP-1RA weight loss therapy effectively mitigate muscle mass loss. Patients receiving HIFEM+RF interventions not only maintained but increased their muscle mass by 1.0 lb, resulting in a net difference of 3.9 lbs in muscle mass between the groups.

6. Acknowledgements

Authors have no acknowledgements to declare. No funding was provided for this research, authorship or publication.

7. Conflict of Interest

Dr. McCoy is an Advisory Board Member, clinical investigator, and speaker for BTL Industries, the manufacturer of the study device. Dr. Shoeff is a clinical investigator and speaker for BTL Industries, and Dr. Goldfarb is a clinical investigator for BTL Industries. However, no funding for the research, authorship, or publication of this article was provided.

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