Muscle ArchitectureNCT07512570
Feasibility and Preliminary Effects of a Structured Resistance Training Program in Children Aged 10-14 Years
A study testing Progressive Resistance Training Program in people with Muscle Architecture and Ultrasonic Diagnosis, run by Charles University, Czech Republic at 1 site in Czechia.
Trial summary
This study is a randomised controlled pilot trial designed to evaluate the feasibility, safety, and preliminary efficacy of a 12-week resistance training intervention in children aged 10-14 years. Read more about this study
- Who is it for?
- Ages 10 to 14 yearsHealthy volunteers can take part
- Conditions the study is for
- Muscle Architecture, Ultrasonic Diagnosis
- What is being tested?
- Progressive Resistance Training Program
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 31 participants
- Where
- 1 siteCzechia
- Study dates
- 1 Sep 2026to 30 Sep 2028
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 10 to 14 years
- All sexes
- Healthy volunteers accepted
- Child
Who may be able to join
- Children aged 10-14 years
- Ability to safely participate in supervised resistance training
- Written informed consent from a parent or legal guardian
- Assent provided by the child participant
- Willingness to comply with all study procedures and attend training sessions
Who cannot join
- Acute illness at the time of enrolment
- Recent musculoskeletal injury or immobilisation
- Chronic cardiovascular, metabolic, or endocrine disorders
- Use of medications that may affect muscle composition or function
- Any medical or psychological condition that may compromise safety or adherence
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Czechia1 site
Faculty of Physical Education and Sport Charles University
Prague, Czech Republic, 16200
About this study
Official title: Feasibility and Preliminary Effects of a Structured Resistance Training Programme in Children Aged 10-14 Years: A Randomised Controlled Pilot Study
This study is a randomised controlled pilot trial designed to evaluate the feasibility, safety, and preliminary efficacy of a 12-week resistance training intervention in children aged 10-14 years. The study adheres to the CONSORT extension for randomised pilot and feasibility trials and incorporates key elements of the SPIRIT guidelines for clinical trial protocols.
The primary purpose of the study is to assess feasibility-related outcomes and to generate effect size estimates to inform the design of a subsequent fully powered randomised controlled trial (RCT).
- Conditions
- Muscle Architecture, Ultrasonic Diagnosis
- Being tested
- Progressive Resistance Training Program
- Keywords
- Resistance Training, Children, Feasibility Study
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Progressive Resistance Training ProgramBehavioural
An 8-week supervised progressive resistance training (PRT) program performed twice weekly in children aged 10-14 years. Each ~45-minute session includes a warm-up, whole-body resistance exercises (with emphasis on lower-limb musculature), and a cool-down. Exercises include squat variations, hip hinge movements, unilateral lower-limb exercises, upper-body pushing and pulling, and core stabilization.
Training intensity is prescribed using a youth-specific rating of perceived exertion (RPE 5-8), with progressive overload applied individually based on proper technique. The program is divided into three phases: familiarisation (weeks 1-2), progressive overload (weeks 3-5), and strength-oriented training (weeks 6-8). Sessions are delivered in small groups under qualified supervision to ensure safety and adherence.
| Study group | Role | What they receive |
|---|---|---|
| Structured Progressive Resistance Training Program | Experimental | Participants will complete an 8-week supervised progressive resistance training (PRT) program performed twice weekly. Each ~45-minute session includes a warm-up, whole-body resistance exercises (with emphasis on lower limbs), and a cool-down. Exercises include squat variations, hip hinge movements, unilateral lower-limb exercises, upper-body pushing/pulling, and core stabilization.
Training intensity is guided by a youth-specific RPE scale (5-8), with progressive overload based on individual technique. Sessions are delivered in small groups under qualified supervision to ensure safety and adherence.
The program consists of three phases: familiarisation (weeks 1-2), progressive overload (weeks 3-5), and strength-oriented training (weeks 6-8). Outcomes are assessed pre- and post-intervention. Receives: Behavioral: Progressive Resistance Training Program |
What is being measured
The primary outcome is the main question the study is designed to answer.
Muscle Quality (Echo Intensity)
Ultrasound-derived echo intensity (EI) of the quadriceps femoris (QF) muscle assessed as an indicator of skeletal muscle quality. EI will be derived from longitudinal scans of each QF head and the cross-sectional area (CSAQF) from panoramic mid-thigh images
Measured: Time Frame: Pre-intervention (baseline) and post-intervention (8 weeks)
Muscle Strength (Knee Extensor Strength)
Maximum voluntary contraction (MVC) of knee extensors measured using an isokinetic dynamometer.
Measured: Time Frame: Pre-intervention and post-intervention (8 weeks)
Feasibility of the Intervention
Feasibility assessed by recruitment rate, retention rate, and adherence to the training program (percentage of sessions attended and proportion of participants attending ≥80% of sessions).
Measured: Throughout the 8-week intervention
Safety of the Intervention
Safety evaluated by the number, type, and severity of adverse events recorded during training sessions, and the proportion of participants experiencing at least one adverse event.
Measured: Throughout the 8-week intervention
Secondary outcomes (2)
Functional Performance
Functional lower-body performance assessed using the 30-second sit-to-stand test (30STS).
Measured: Pre-intervention and post-intervention (8 weeks)
Body Composition
Body composition assessed using dual-energy X-ray absorptiometry (DXA), including lean mass and fat mass parameters.
Measured: Pre-intervention and post-intervention (8 weeks)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Apr 2026
- Study start1 Sep 2026 (estimated)
- Primary completion31 Dec 2027 (estimated)
- Study completion30 Sep 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Muscle ArchitectureStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 31 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Charles University, Czech Republic
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Michal Šteffl, Charles University, Czech Republic
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07512570
- Sponsor's protocol ID
- EK 007/2026
- Status last verified
- Apr 2026
- First submitted
- 26 Mar 2026
- Last updated
- 6 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 6 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Feasibility and Preliminary Effects of a Structured Resistance Training Programme in Children Aged 10-14 Years: A Randomised Controlled Pilot Study
- ClinicalTrials.gov ID
- NCT07512570
- Acronym / sponsor ID
- EK 007/2026
- Conditions
- Muscle Architecture, Ultrasonic Diagnosis
- Keywords
- Resistance Training, Children, Feasibility Study
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 31 participants (estimated)
- Lead sponsor
- Charles University, Czech RepublicUniversity, hospital or other
- Study start
- 1 Sep 2026 (estimated)
- Primary completion
- 31 Dec 2027 (estimated)
- Study completion
- 30 Sep 2028 (estimated)
- First posted
- 6 Apr 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study is a randomised controlled pilot trial designed to evaluate the feasibility, safety, and preliminary efficacy of a 12-week resistance training intervention in children aged 10-14 years. The study adheres to the CONSORT extension for randomised pilot and feasibility trials and incorporates key elements of the SPIRIT guidelines for clinical trial protocols.
The primary purpose of the study is to assess feasibility-related outcomes and to generate effect size estimates to inform the design of a subsequent fully powered randomised controlled trial (RCT).
Study design
- Primary purpose
- Prevention
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Structured Progressive Resistance Training Program | Experimental | Behavioral: Progressive Resistance Training ProgramParticipants will complete an 8-week supervised progressive resistance training (PRT) program performed twice weekly. Each ~45-minute session includes a warm-up, whole-body resistance exercises (with emphasis on lower limbs), and a cool-down. Exercises include squat variations, hip hinge movements, unilateral lower-limb exercises, upper-body pushing/pulling, and core stabilization. Training intensity is guided by a youth-specific RPE scale (5-8), with progressive overload based on individual technique. Sessions are delivered in small groups under qualified supervision to ensure safety and adherence. The program consists of three phases: familiarisation (weeks 1-2), progressive overload (weeks 3-5), and strength-oriented training (weeks 6-8). Outcomes are assessed pre- and post-intervention. |
Who may qualify
- Ages
- 10 to 14 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child
Key inclusion criteria (5 listed)
- Children aged 10-14 years
- Ability to safely participate in supervised resistance training
- Written informed consent from a parent or legal guardian
- Assent provided by the child participant
- Willingness to comply with all study procedures and attend training sessions
Key exclusion criteria (5 listed)
- Acute illness at the time of enrolment
- Recent musculoskeletal injury or immobilisation
- Chronic cardiovascular, metabolic, or endocrine disorders
- Use of medications that may affect muscle composition or function
- Any medical or psychological condition that may compromise safety or adherence
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Progressive Resistance Training ProgramAn 8-week supervised progressive resistance training (PRT) program performed twice weekly in children aged 10-14 years. Each ~45-minute session includes a warm-up, whole-body resistance exercises (with emphasis on lower-limb musculature), and a cool-down. Exercises include squat variations, hip hinge movements, unilateral lower-limb exercises, upper-body pushing and pulling, and core stabilization. Training intensity is prescribed using a youth-specific rating of perceived exertion (RPE 5-8), with progressive overload applied individually based on proper technique. The program is divided into three phases: familiarisation (weeks 1-2), progressive overload (weeks 3-5), and strength-oriented training (weeks 6-8). Sessions are delivered in small groups under qualified supervision to ensure safety and adherence. | Behavioural | Structured Progressive Resistance Training Program |
Primary outcome
Muscle Quality (Echo Intensity)
Time frame: Time Frame: Pre-intervention (baseline) and post-intervention (8 weeks)
Ultrasound-derived echo intensity (EI) of the quadriceps femoris (QF) muscle assessed as an indicator of skeletal muscle quality. EI will be derived from longitudinal scans of each QF head and the cross-sectional area (CSAQF) from panoramic mid-thigh images
Muscle Strength (Knee Extensor Strength)
Time frame: Time Frame: Pre-intervention and post-intervention (8 weeks)
Maximum voluntary contraction (MVC) of knee extensors measured using an isokinetic dynamometer.
Feasibility of the Intervention
Time frame: Throughout the 8-week intervention
Feasibility assessed by recruitment rate, retention rate, and adherence to the training program (percentage of sessions attended and proportion of participants attending ≥80% of sessions).
Safety of the Intervention
Time frame: Throughout the 8-week intervention
Safety evaluated by the number, type, and severity of adverse events recorded during training sessions, and the proportion of participants experiencing at least one adverse event.
2 secondary outcomes
Functional Performance
Time frame: Pre-intervention and post-intervention (8 weeks)
Body Composition
Time frame: Pre-intervention and post-intervention (8 weeks)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Apr 2026.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Progressive Resistance Training Program in people with Muscle Architecture and Ultrasonic Diagnosis, run by Charles University, Czech Republic at 1 site in Czechia.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 6 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Czechia. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Michal Steffl, PhD (+420778701882, michal.steffl@ftvs.cuni.cz), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Muscle Quality (Echo Intensity) (time frame: Time Frame: Pre-intervention (baseline) and post-intervention (8 weeks)). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Apr 2026.