The Effect of Diathermy Therapy on Isolated Lumbar Extension (ILEX) Training (ILEX)

To evaluate the effectiveness of the Isolated Back Extension (ILEX) machine Myosom and examine the influence of preheating on resistance training, the investigators will recruit a cohort of 14 healthy individuals, including both male and female participants, who have no prior experience with ILEX training, for a 9-week training program consisting of a total of 18 sessions. Baseline (BL) measurements will be conducted in the week before the initiation of training, and two follow-up measurements (F/U 1 and F/U 2) carried out after the ninth and eighteenth sessions, with a minimum break of 48 hours after the last training session to ensure proper recovery and to prevent inaccuracies in muscle thickness measurement arising due to acute oedema.

Study Overview

• Status: Completed
• Conditions: Resistance Training; Healthy Participants Study
• Intervention / Treatment: Other: CRET Therapy; Other: ILEX training; Other: CRET therapy sham

Detailed Description

To evaluate the effectiveness of the Isolated Back Extension (ILEX) machine Myosom and examine the influence of preheating on resistance training, the investigators will recruit a cohort of 14 healthy individuals, including both male and female participants, who have no prior experience with ILEX training, for a 9-week training program consisting of a total of 18 sessions. Baseline (BL) measurements will be conducted in the week before the initiation of training, and two follow-up measurements (F/U 1 and F/U 2) carried out after the ninth and eighteenth sessions, with a minimum break of 48 hours after the last training session to ensure proper recovery and to prevent inaccuracies in muscle thickness measurement arising due to acute edema.

At BL, participants will need to give written informed consent and be familiarized to the back extensor machine and Category-Ratio-Scale (CR10) for the assessment of perceived effort and discomfort as well as thermal sensation and thermal comfort. Baseline assessment will include epidemiological data such as age, sex, height, and weight. At all three measurements (BL, F/U 1, F/U 2), the lumbar extensor musculature thickness (M. erector spinae) is evaluated through the ultrasound system Mylab2 (Esaote, Maastricht, Netherlands), the lower back flexibility is examined using a sit-and-reach test, and the isometric back extension endurance is measured through the Biering-Sørrensen test. Finally, maximal range of motion (ROM) and maximal voluntary isometric contraction will be evaluated using the Myosom machine.

Participants will be randomly assigned to either the sham group, which will receive a 10-minute treatment with Tecar device (T-Plus, Wintecare SA, Chiasso, Switzerland) turned off and not sending radiofrequency before each exercise session, or the intervention group, which will undergo a 10-minute treatment with the Tecar device to induce 448kHz capacitive monopolar radiofrequency and facilitate warming up of deep tissues. After every treatment the participants will be asked to rate their thermal sensation and comfort. Skin temperature will be measured using an infrared thermal imaging (FLIR A615 series, Emitec Industrial, Rotkreuz, Switzerland) after the first and final Tecar treatment.

Training will take place twice a week, beginning with a dynamic warm-up of the lumbar extensor for 120s, followed by three sets of resistance training (RT) lasting 120s, 120s, and 150s respectively, and concluding with a final set of dynamic recovery lasting 60s. 30-second recovery will be provided between every set. A low load will be used for the warm-up and recovery. The load will be subsequently increased until volitional fatigue. Repetitions will be executed by taking three seconds from complete flexion to complete extension, ensuring standardization at 20 repetitions per minute. A metronome with 40 beats per minute will provide audible feedback. The Myosom machine emits an audible signal upon completion of each phase of the repetition to guarantee a complete range of motion is achieved. Subsequent to every training session, participants will be requested to provide their effort (RPE-E) and discomfort (RPE-D) values.

• Study Type: Interventional
• Enrollment (Actual): 25
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Kanton Graubünden
    • Landquart, Kanton Graubünden, Switzerland, 7302
      • University of Applied Sciences and Arts of Southern Switzerland

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• healthy
• pain-free
• sufficient understanding of the German language
• able to give informed consent
• between 18 and 30

Exclusion Criteria:

• pregnant
• medication
• surgery of lumbar spine
• knee or hip disorders
• low back pain
• pathologies or deformities of lumbar spine
• other disorders
• previous or current ILEX Training

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention group; Capacitive Resistive Electric Transfer (CRET) therapy AND Isolate Lumbar Extension (ILEX) Training.	Other: CRET Therapy; Diathermy therapy with a protocol to preheat the back extensor muscle; Other Names: TECAR therapy; Diathermy therapy; Other: ILEX training; Isolated lumbar Extension Training
Sham Comparator: Sham Group; Sham Capacitive Resistive Electric Transfer (CRET) therapy AND Isolate Lumbar Extension (ILEX) Training.	Other: ILEX training; Isolated lumbar Extension Training; Other: CRET therapy sham; Diathermy therapy withouth any radiofrequency as a sham intervention; Other Names: TECAR therapy; Diathermy therapy

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
maximal isometric force of the back extensors	measured on the ILEX machine in Newton	base line, 3 weeks, 6 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
isometric back extension endurance	Biering- Sørensen test	base line, 3 weeks, 6 weeks
Thickness of the Mm. erector spine	Ultrasound	base line, 3 weeks, 6 weeks
Lumbar flexibility	Sit and reach test	base line, 3 weeks, 6 weeks
Lumbar R.O.M.	ILEX machine	base line, 3 weeks, 6 weeks
rating of perceived effort	Category Ratio Scale (0-10)	After each of the 12 training sessions, twice a week for 6 weeks
rating of perceived discomfort	Category Ratio Scale (0-10)	After each of the 12 training sessions, twice a week for 6 weeks
rating of thermal sensation	9 point likert scale (4 / -4)	After each of the 12 therapy sessions, twice a week for 6 weeks
rating of perceived comfort	5 point likert scale (0-4)	After each of the 12 therapy sessions, twice a week for 6 weeks

Collaborators and Investigators

• Sponsor: University of Applied Sciences and Arts of Southern Switzerland
• Investigators: Principal Investigator: Ron Clijsen, PhD, University of Applied Sciences and Arts of Southern Switzerland

Study record dates

Study Major Dates

• Study Start (Actual): April 29, 2024
• Primary Completion (Actual): April 15, 2025
• Study Completion (Actual): April 15, 2025

Study Registration Dates

• First Submitted: May 7, 2024
• First Submitted That Met QC Criteria: February 27, 2025
• First Posted (Actual): February 28, 2025

Study Record Updates

• Last Update Posted (Estimated): October 3, 2025
• Last Update Submitted That Met QC Criteria: September 29, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Keywords: Thermal Therapy; Isolated lumbar extension training; lumbar muscle
• Additional Relevant MeSH Terms: Wounds and Injuries; Body Temperature Changes; Heat Stress Disorders; Hyperthermia
• Other Study ID Numbers: 2023-02308_ILEX

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No