Completed NA INTERVENTIONAL 6-arm NCT06698055

Muscle Adaptations in Children and Adults Following Twelve Weeks of Flywheel or Weight Stack Resistance Exercise (KidREx)

KidREx - Muscle Adaptations in Children and Adults Following a Twelve-week of Resistance Exercise Period Using Either Flywheel or Traditional Weight Stack Devices - a Randomized Controlled Study

Sponsor: Björn Alkner

Conditions Children, Adult EMG Growth Plate Early Closing Magnetic Resonance Imaging Muscle Hypertrophy Resistance Exercise Skeletal Muscle

Interventions Flywheel Resistance Exercise Weight Stack Resistance Exercise

Updated 2 times since 2024 Last updated: Dec 8, 2025 Started: Aug 28, 2022 Primary completion: Feb 2, 2025 Completion: Feb 12, 2025

This information is for research purposes only and is not medical advice. Consult a healthcare provider before making any medical decision.

This NA trial investigates Children, Adult and EMG and is currently completed. Björn Alkner leads this study, which shows 2 recorded versions since 2022 — indicating limited longitudinal coverage. The change history captured here reflects the iterative nature of clinical trial conduct.

Status Flow

Change History

2 versions recorded

Jan 2026 — Present [monthly]

Completed NA

Status: Recruiting → Completed
Dec 2024 — Jan 2026 [monthly]

Recruiting NA

First recorded

Aug 2022

Trial started

Per CT.gov start date — pre-dates our first snapshot

Eligibility Summary

No eligibility information available.

Contact Information

Sponsor contact:

Björn Alkner
Karolinska Institutet
Linkoeping University
Medical Research Council of Southeast Sweden
Swedish Research Council for Sport Science
The Swedish Research Council
Umeå University

Data source: Region Jönköping County

For direct contact, visit the study record on ClinicalTrials.gov .

Study Locations

• Eksjö, Sweden