The effect of resistance training, electrical muscle stimulation (EMS) and vitamin D supplementation on the regulation of microRNAs miR-486 and miR-206, serum concentrations of insulin-like growth factor 1 (IGF-1), myostatin and fibroblast growth factor 21 (FGF-21), and physical performance indices in patients with heart failure with reduced ejection fraction and sarcopenia

Determining the effect of resistance training, EMS, and vitamin D on the expression of miR-486 and miR-206, serum levels of IGF-1, myostatin, and FGF-21, and physical performance indices in heart failure patients with sarcopenia

Randomized, controlled, 5-group, parallel-group, single-blind, phase 3 clinical trial on 25 patients with HFrEF and sarcopenia (5 per group). Allocation to control, vitamin D, resistance training, EMS, and exercise + vitamin D groups

This study will be conducted at Shahid Rajaee Cardiovascular Institute, Tehran. Screening, confirmation of HFrEF and echocardiography will be performed in the Heart Failure Clinic, and sarcopenia assessment with PMCSA at T4 level will be performed by the imaging department. Resistance training and EMS interventions and supplementation will be implemented. Blood sampling and molecular and biochemical assays will also be performed in a standard laboratory.

Inclusion: Stable heart failure (HFrEF), sarcopenia confirmed by PMCSA on T4 CT scan, serum vitamin D level of approximately 20 ng/ml, ability to exercise. Exclusion: Pacemaker/ICD, unstable arrhythmia, absence of more than 2 consecutive sessions, and change of muscle-affecting medications.

1- Control group 2- Vitamin D supplement group 3- Resistance training group (RT) 4- Electrical stimulation group (EMS) 5- Exercise and supplement group

Physical performance indices: grip strength with a hand-held dynamometer, walking speed with a 4-meter test, and balance with a leaf balance scale. Biological markers: serum concentrations of IGF-1, myostatin, and FGF-21 by ELISA; relative expression of miR-486 and miR-206 in peripheral blood by RT-qPCR; and serum 25(OH)D levels to monitor the effect of supplementation.

SubjectGiven the nature of the interventions in this study (resistance training and Electromyostimulation - EMS), blinding the participants and the training instructors is not feasible due to the overt and tangible nature of the interventions. However, to minimize potential bias and enhance the scientific validity of the study, blinding is strictly implemented at the following levels: Blinding of Outcome Assessors: All individuals responsible for phlebotomy, laboratory biochemical analysis, and physical performance testing are completely blinded to the participants’ group assignments. Blood samples will be sent to the laboratory using a coding system to prevent any potential bias in the results. Blinding of Data Analyst: The statistician performing the data analysis will receive the data labeled with group codes (e.g., Group A, B, and C) and will remain blinded to the identity of the intervention groups until the data analysis phase is finalized. Therefore, the present study is designed as a single-blind trial, with a focus on blinding the assessment and data analysis teams to prevent the influence of potential biases on the reported outcomes.s

De-identified individual participant data will be available, including baseline demographic and clinical characteristics, intervention group allocation, primary outcome data (relative expression of miR-486 and miR-206, and serum concentrations of IGF-1, myostatin, and FGF-21), secondary outcome data (handgrip strength, gait speed, Berg Balance Scale score, and serum 25(OH)D level), and the data dictionary. All direct identifiers and potentially identifying information will be removed before data sharing. The study protocol and statistical analysis plan will also be available upon request.

Data will be available beginning 6 months after publication of the primary study results and will remain available for 5 years after the publication date.

Researchers affiliated with universities, research institutions, healthcare centers, or other recognized scientific organizations may submit a data-access request. Applicants must have relevant scientific qualifications and a methodologically sound research or analysis proposal.

Data may be used only for scientific analyses relevant to the study objectives, valid secondary research, meta-analyses, or replication and verification of the study findings. Access requests must include the research objective, analysis plan, research-team details, and a commitment to confidentiality. Access will be conditional upon approval by the principal investigator, compliance with research ethics requirements, execution of a data-use agreement, and agreement not to attempt re-identification of participants or transfer data to third parties. Commercial use, redistribution of raw data, or use beyond the approved objectives will not be permitted.

Applicants should submit a written request to the principal investigator of the study. Requests may be submitted and followed up through the principal investigator’s official email address: Principal Investigator: [Samaneh Ebrahimi] Email: [ebrahimi.mailbox@gmail.com] Affiliation: Rajaie Cardiovascular Medical and Research Center, Tehran, Iran.

Applicants must submit a written request including the study title and objective, a brief research protocol, proposed analysis plan, research-team details, institutional affiliation, and ethics approval when required. The request will be reviewed for scientific relevance, feasibility, ethical considerations, and protection of confidentiality. A decision will be communicated within a maximum of 30 working days. If approved, and after execution of a data-use agreement, the agreed de-identified data files and supporting documents will be provided through a secure transfer method.

Shared data will contain no direct personal identifiers. Given the small sample size and the sensitivity of clinical information from patients with heart failure, some potentially identifying variables may be removed, aggregated, or restricted to minimize the risk of indirect participant re-identification.