Effects of home-based strength training with different intensities on muscle strength and physical functions in patients with Duchenne muscular dystrophy: Study protocol for an exploratory pilot randomized controlled trial

Abstract

Background: Regular submaximal strengthening exercises are recommended for patients with Duchenne muscular dystrophy (DMD); however, evidence regarding the optimal intensity is limited.
Objective: To evaluate the effects of a 12-month home-based strength training program at different intensities on muscle strength and physical function in boys with DMD and inform the design of a future definitive randomized controlled trial (RCT).
Study design: Single-site, parallel-group, exploratory pilot RCT.
Methods: Sixty boys aged 5-10 years with DMD will be randomized in a 1:1:1 ratio to non-resistance, low-resistance, or moderate-resistance strength training groups. All groups will perform a standardized exercise regimen thrice weekly for 12 months at home, including warm-up, static stretching, and strengthening exercises. Training will be initiated through a face-to-face instructional session. Adherence and safety will be monitored using exercise logs and biweekly telephonic assessments. Primary and secondary outcomes will be assessed at baseline, 6 months, and 12 months by blinded outcome assessors.
Outcome measures: Primary outcome measures are muscle strength and the North Star Ambulatory Assessment. Secondary outcomes include the Motor Function Measure, timed function tests, range of motion, and Vignos and Brooke scales. The exploratory outcomes comprise feasibility (eligibility, recruitment rate, intervention adherence, and study completion rate), tolerability (nonadherence and withdrawal), and safety (adverse events, serum creatine kinase levels, and muscle pain).
Conclusions: This Chinese exploratory RCT will provide critical data on the preliminary effects and feasibility of home-based strength training at different intensities in DMD. These findings will guide sample size calculation and outcome selection for larger multicenter trials.

Keywords

Duchenne muscular dystrophy / Children / Strength training / Different intensities / Exercise / Exploratory randomized controlled trial

CRediT authorship contribution statement

Zhen Huang: Writing - review & editing, Supervision, Investigation, Conceptualization,Methodology. Wenzhu Li: Writing - review & editing, Writing - original draft, Project administration, Methodology, Funding acquisition, Data curation, Conceptualization. Rongli Wang: Writing - review & editing, Conceptualization. Ninghua Wang: Writing - review & editing, Conceptualization. Xueying Li: Writing - review & editing, Software, Methodology, Conceptualization. All the authors have read and approved the final version of this manuscript.

Ethics approval

This study was approved by the Research Ethics Committee of Peking University First Hospital (Study ID: 2019-159). This study will be conducted in accordance with the international standards of Good Clinical Practice (GCP) and the ethical principles of the Declaration of Helsinki (2013 revision). Written informed consent will be obtained from the parents/guardians, assent will be obtained from children aged ≥ 8 years, who can withdraw at any time. Contact details will be provided to the parents or guardians for queries. The results will be disseminated through peer-reviewed publications and conference presentations.

Funding

This study was supported by the Youth Clinical Research Project of Peking University First Hospital (Grant number: 2019CR11). The funder and sponsor reviewed the design of the trial, but did not have any role in writing or submitting this paper for publication. The views expressed are those of the authors and not necessarily those of the Department of Rehabilitation Medicine at Peking University First Hospital.

Data availability

The de-identified datasets generated and analyzed during this study will be available from the corresponding author upon reasonable request, subject to approval by the institutional ethics committee and compliance with data protection regulations.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Declaration of Generative AI and AI-assisted technologies in the writing process

The authors declare that they did not use any generative AI or AI-assisted technologies in the conceptualization, design, or drafting of the manuscript. The authors take full responsibility for the integrity and originality of the work presented.

Acknowledgments

None.

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