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Child DevelopmentkettleclassNCT06910085

Kettlebell-classroom Training

A study testing kettlebell-training in people with Child Development and Schools, run by University Hospital, Basel, Switzerland at 1 site in Switzerland.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

Physical fitness is a crucial health marker, predicting both cardiovascular and all-cause mortality. Muscular strength, an essential component of physical fitness, underpins physical and psychological well-being, particularly from childhood. Read more about this study

Who is it for?
Ages 6 to 9 yearsHealthy volunteers can take part
Conditions the study is for
Child Development, Schools, Primary Health Care
What is being tested?
kettlebell-training
Could I receive a placebo?
No, everyone receives an active treatment
How many people
92 participants
Where
1 siteSwitzerland
Study dates
21 Oct 2024to 6 Dec 2024
Phase
Interventional
Are there results?
None posted in the registry

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 6 to 9 years
  • All sexes
  • Healthy volunteers accepted
  • Child

Who may be able to join

  • all of the selected second-graders who can participate in physical education lessons will be included in the study

Who cannot join

  • Children with a medical certificate, that prohibits physical activity, will be excluded from performance testing and training intervention.

Trial locations and contacts

1 site in 1 country.

Switzerland1 site
  • Department of Sport, Exercise and Health

    Basel, Basellandschaft, 4052

Other trials in Switzerland

About this study

Official title: Kettlebell-classroom: Feasibility and Effect of a Daily Dose of Resistance Training in Primary School Children - a Control\ed Trial

Physical fitness is a crucial health marker, predicting both cardiovascular and all-cause mortality. Muscular strength, an essential component of physical fitness, underpins physical and psychological well-being, particularly from childhood. Increasing sedentary behavior has led to rising obesity and cardiovascular disease rates in children, exacerbated by the COVID-19 pandemic and the emergence of pediatric dynapenia. Muscular fitness positively affects body composition, bone health, psychological health, and academic performance, and is necessary for fundamental motor skills.

In Basel, a ten-year trend shows declining physical fitness and rising obesity among primary school children, especially those from lower socio-economic backgrounds with less access to sports. This presents an opportunity to promote physical activity in schools. The "Kettlebell Classroom" project aims to introduce daily, playful resistance training with kettlebells over seven weeks in various schools, focusing on culturally and socially less integrated children.

Evidence supports the benefits of resistance training (RT) for children, including increased joint stability, improved motor skills, reduced injury risks, and increased spontaneous physical activity. Despite WHO recommendations for muscle and bone-strengthening activities three times a week, these guidelines are often unmet. This project aims to demonstrate the effectiveness of short, intensive exercise sessions for children, with the goal of expanding the initiative across Basel to improve health outcomes for all children.

Read the detailed description

Study intervention The intervention emphasizes full-body exercises which are performed with the own body weight and kettlebells. On every weekday, the intervention classes will receive 15 min of supervised training over 7 weeks. This results in a total number of training sessions of 35 sessions. The movements and exercises in all phases are based on functional, multi-joint movements. The focus will be on age-appropriate whole-body strength and motor skill development. It will be designed with different, varying exercises, which can be individually tailored and adapted to the children's ability. Tailored to the group, the sessions will also include parts which engage social cooperation and teamwork, so that the children will experience a sense of competence, self-determination and enjoyment of exercise while enhancing motor skills and athletic ability.

Being tested
kettlebell-training
Keywords
Kettlebell Training, Daily school routine, Teacher involvement, Primary school, Physical education

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • kettlebell-trainingBehavioural

    15 min of body weight or kettlebell loaded strength training

Study groups in NCT06910085
Study groupRoleWhat they receive
kettlebell trainingActive comparatorThe intervention involves daily, supervised resistance training sessions for primary school children, integrated directly into the classroom setting. Over a period of 7 weeks, participating second-grade school classes perform 15-minute kettlebell-based workouts every school day, totaling 35 sessions. The sessions are designed to be: Playful and age-appropriate Focused on whole-body strength and motor skill development Based on functional, multi-joint movements using bodyweight and kettlebells Adaptable to individual ability levels Including elements of teamwork and cooperation to enhance motivation and enjoyment The goal is to improve muscular strength, coordination, fitness, and psychosocial well-being, particularly in children from lower socio-economic backgrounds.
Receives: Behavioral: kettlebell-training
regular schedule - controlNo interventionThe control group consists of parallel second-grade school classes that do not receive any active intervention during the study period. These students continue with their regular school routine and standard physical education classes, without the additional kettlebell training sessions. Like the intervention group, they: Undergo the same pre- and post-intervention test battery assessing strength, coordination, fitness, and anthropometric measures Are assessed during school hours using identical equipment and protocols Serve as a baseline comparator to evaluate the effectiveness and feasibility of the resistance training intervention

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Maximal strength

    The mid-thigh pull is measured on the force plate, as is the hand grip force (Leonardo Mechanograph® Novotec Medical GmbH, Pforzheim, Germany). The mid-thigh pull corresponds to a static deadlift, i.e. pulling up a bar in the centre of the thigh, and thus provides an image of the force transmission of the muscle loops up to the hand force to transfer the force to the measuring device. The test subject has a hip and knee angle of 135-140° and tries to pull as quickly and strongly as possible on the vertically fixed bar in the centre of the thigh. As the test subject is standing on the force plate, the transmitted force is measured precisely. In contrast to the dynamic 1-repetition maximum, this simple test offers a high level of safety as an isometric measurement and, in particular, has a high test-retest reliability. This measurement is therefore not only attractive to perform, but also makes it easy to analyse strength curves and maximum strength.

    Measured: seven week intervention

Secondary outcomes (8)
  1. Handgrip strength

    The handgrip force is measured using a size-adjustable application to take into account the span of the respective hand size. The measurement is performed with the arm extended vertically and provides a safe and reliable measurement for children.

    Measured: seven week intervention

  2. sprint performance

    20 m Sprint: Electronic measurement of a timed (seconds) 20 m sprint, starting from a resting position. Start follows after an acoustic signal, with a precision of 1/100 second.

    Measured: seven week intervention

  3. jump performance

    Countermovement jump: Power per body mass, determined from a vertical countermovement jump (CMJ), has been shown to be correlated to leg extension strength in children while representing a more natural movement. The CMJ will be performed on a force plate (Leonardo Mechanograph®, Novotec medical, Pforzheim, Germany) with arms akimbo. The instruction will be to jump as high as possible. After familiarization, each participant performs 2-5 trials, with the best of the two trials with <5% difference being used for the analysis. The most important outcome parameter of this test is the maximum power output (peak power) normalized to body weight. The CMJ had a high intra-trial reproducibility (ICC>0.95) in 6-8 year old children, whereas inter-session variation has been reported to be high in children aged 6-12 years as well (ICC=0.95, SEE=1.92 standard error of estimate).

    Measured: seven week intervention

  4. shuttle-run performance

    20 m Shuttle-Run-test: This is a validated test which measures aerobic capacity by running forth and back for 20 m, with an initial running pace of 8.0 km/h and a progressive 0.5 km/every minute raise of the running speed given by a sound. The maximal performance will be reached when the child does not cross the 20 m line at the moment of the beep for two consecutive 20 m distances. Number of "paliers" (1 palier≅1 minute) performed will be counted with a precision of 0.5 paliers.

    Measured: seven week intervention

  5. balance performance

    This test of coordination includes balancing backward on 3 m long bars with a width of 3, 4.5, and 6 cm, respectively. The number of steps until the child's foot touches the floor will be counted; 3 trials will be performed for each bar width. The sum of these 9 tests will be used for statistical analysis.

    Measured: seven week intervention

  6. object control

    The Eye-Hand-Control test is valid and reliable and determines the level of controlling an object (tennis ball) while conducting repetitive movements (i.e., left-hand throw, right-hand catch, or right-hand throw, and left-hand catch, etc.) as frequently as possible in a time-constrained task of 30 sec. The children are free to use overhand and/or underhand techniques or a combination of both for throwing and catching. Children had to stand 1 m from a wall and throw the tennis ball at eye level on a wall. Participants conducted this test twice, with the number of successful ball catches across both trials resulting in the test score.

    Measured: seven week intervention

  7. blood pressure, body composition

    Anthropometry and blood pressure will be analysed on a seperate day, in a separate room parallel to the usual school lessons. 3 students will be evaluated at the same time.

    Measured: seven week intervention

  8. side hop

    Jumping sidewards: Measurement for speed and coordination. Jumping with both legs together on alternating sides of a bunton of wood, as many times as possible, within 15 seconds. Two trials will be performed. The number of jumps will be counted. The sum of the number of jumps of the two tests will be used for statistical analysis.

    Measured: seven week intervention

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted4 Apr 2025
  2. Study start21 Oct 2024
  3. Primary completion6 Dec 2024
  4. Study completion6 Dec 2024

Resources

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
Non-randomised
Intervention model
Parallel groups
Masking
None (open label)
Enrolment
92 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06910085
Sponsor's protocol ID
2024-01074
Other IDs
2024-01074
Acronym
kettleclass
Status last verified
Mar 2025
First submitted
27 Mar 2025
Last updated
4 Apr 2025
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No: No, because data is very sensible due to age of the participants.

Publications

  • Braun N, Ledergerber R, Lichtenstein E, Nebiker L, Roth R. Classroom-Integrated Kettlebell Training: Effects on Motor Performance, Attention, and Health in Primary School Children. J Sch Health. 2026 Apr;96(4):e70136. doi: 10.1111/josh.70136.

    PubMed 41854388

Questions about this trial

What is this clinical trial studying?

A study testing kettlebell-training in people with Child Development and Schools, run by University Hospital, Basel, Switzerland at 1 site in Switzerland.

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 1 inclusion and 1 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: finished, as of the sponsor's last update on 4 Apr 2025. 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 Switzerland. 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?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Maximal strength (time frame: seven week intervention). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06910085, which also lists 1 linked publication.

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 4 Apr 2025.

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