Muscle Architecture, Ultrasonic Diagnosis
Conditions
Keywords
Resistance Training, Children, Feasibility Study
Brief 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. 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).
Interventions
BEHAVIORALProgressive Resistance Training Program
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.
Sponsors
Charles University, Czech Republic
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
10 Years to 14 Years
Healthy volunteers
Yes
Inclusion criteria
* 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
Exclusion criteria
* 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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Muscle Quality (Echo Intensity) | 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: Pre-intervention and post-intervention (8 weeks) | Maximum voluntary contraction (MVC) of knee extensors measured using an isokinetic dynamometer. |
| Feasibility of the Intervention | 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 | 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. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Functional Performance | Pre-intervention and post-intervention (8 weeks) | Functional lower-body performance assessed using the 30-second sit-to-stand test (30STS). |
| Body Composition | Pre-intervention and post-intervention (8 weeks) | Body composition assessed using dual-energy X-ray absorptiometry (DXA), including lean mass and fat mass parameters. |
Countries
Czechia
Contacts
CONTACTMichal Steffl, PhD
Outcome results
None listed