The Effects of Pink Noise Induction and Differential Resistance Exercise on Motor Performance Indicators and Balance in Elderly Individuals

To compare the effect of pink noise induction, differential resistance training, their combination, and a control condition on the Root Mean Square (RMS) of postural sway in the anterior-posterior (A-P) and medial-lateral (M-L) axes in older adults. To compare the effect of the four interventions on the duration of anticipatory postural adjustments (APAs). To compare the effect of the four interventions on the amplitude of compensatory postural adjustments (CPAs). To compare the effect of the four interventions on the frequency structure (spectral analysis) of the biceps brachii muscle activity during elbow flexion.

A randomized, factorial, single-blind, sham-controlled clinical trial with four intervention groups (Pink Noise, Differential Training, Combined, and Control) conducted in a single phase. The study aims to enroll 48 community-dwelling older adults allocated via stratified block randomization with concealed allocation.

Single-center lab trial with one-session assessments before/after a 30-minute intervention. Single-blind: participants are blinded via identical sham/active devices; the outcome assessor is unblinded.

Inclusion Criteria: Aged 65 years or older. Ability to stand independently without assistive devices. No diagnosed neurological or musculoskeletal disorders affecting balance. Exclusion: Vestibular disorders or severe visual/hearing impairments. Recent history of falls (within the past 6 months).

Pink Noise Group (nGVS only) Differential Training Group (Exercise only) Combined Group (nGVS + Exercise) Sham Control Group

Postural control and balance/ Anticipatory and compensatory postural adjustments/ Postural stability/ Balance performance in older adults/

After baseline assessments and confirmation of eligibility criteria, eligible participants will enter the randomization process. To ensure balanced group sizes and reduce the risk of selection bias, participants will be allocated using a block randomization method. The random allocation sequence will be generated using computer-based randomization software, and variable block sizes (e.g., blocks of 4 and 8) will be used to minimize predictability of group assignment for both researchers and participants. After enrollment, participants will be randomly assigned to one of the following four study groups: Pink Noise Galvanic Vestibular Stimulation group (nGVS only) Differential Resistance Training group (exercise only) Combined Intervention group (nGVS + Differential Resistance Training) Control (Sham) group The random sequence generation and maintenance of allocation codes will be performed by a researcher who is not involved in participant recruitment, outcome assessment, or implementation of the interventions. To ensure allocation concealment, group assignments will be placed in sequentially numbered, opaque, sealed envelopes. After completion of baseline assessments and final enrollment of each participant, the corresponding envelope will be opened by the responsible researcher to determine the assigned study group. All participants will have an equal chance of being allocated to any of the four study groups. In addition, the outcome assessor will remain blinded to participants’ group assignments in order to minimize assessment bias.

This study will use a single-blind design. Participants will be blinded to their assigned intervention group, and they will not be informed about the differences between the active and control conditions. In the sham control group, electrodes will be placed on the mastoid processes in the same manner as in the active stimulation group, and the preparation procedures and session duration will be identical to those of the intervention groups, except that no effective electrical current will be delivered. Therefore, participants will not be aware of whether they are receiving active or sham stimulation. Due to the nature of the exercise intervention, the researcher responsible for administering the training sessions and interventions will be aware of group allocation, and complete blinding of the intervention provider is not feasible. However, outcome assessments will be conducted using standardized and identical procedures for all participants in order to minimize assessment bias. In addition, data analysis will be performed using coded group labels to help maintain objectivity during interpretation of the results.

All deidentified individual participant data (IPD) collected for the primary and secondary outcomes in this study will be shared. This includes: Baseline demographic data (age group, sex, and fall risk category). Pre- and post-intervention data for: Primary Outcome: RMS of COP in AP axis. Secondary Outcomes: All other COP measures (velocity, sample entropy, Romberg ratio in AP/ML), APA/CPA parameters, maximum elbow torque, and biceps EMG frequency spectrum indices. Group allocation code.

Availability Start Date: The deidentified IPD and supporting documents will become available 6 months after the publication of the primary results of this trial in a peer-reviewed journal. Availability Period: The data and documents will be made available for a minimum period of 5 years from the start date.

Deidentified IPD and supporting documents will be shared with any qualified researcher worldwide, irrespective of their affiliation (academic, commercial, or non-profit), provided they submit a methodologically sound research proposal for approval. Eligible Recipients: Researchers from academic institutions, healthcare organizations, industry (e.g., medical device or pharmaceutical companies), and independent research consortia. Access Criteria: Requestors must submit a detailed proposal outlining the scientific objective, analysis plan, and ethical considerations to the study's principal investigator or a designated data access committee. Access will be granted for legitimate scientific inquiry aimed at validation, meta-analysis, or novel secondary analysis. Requestors will be required to sign a data use agreement prohibiting attempts to re-identify participants or misuse the data.

Types of Analyses: Data will be shared for purposes of scientific validation, meta-analysis, or novel secondary research related to aging, sensorimotor function, neurorehabilitation, and balance. Proposals for commercial product development require explicit justification and additional oversight. Review Process: All data access requests will be reviewed by a two-tier committee: Tier 1 (Feasibility & Ethics): The Principal Investigator (PI) and the study's ethics committee representative. Tier 2 (Scientific Merit): An independent panel of two experts in motor control, geriatrics, or biostatistics. Review Criteria: Proposals will be evaluated based on Scientific Rigor: Sound methodology and a clear analysis plan. Ethical Alignment: No intent for re-identification or harmful use. Resource Feasibility: Reasonable scope that can be supported by the provided data. Non-Redundancy: The analysis should not duplicate already published work from the primary team. Access Mechanism: Approved researchers will be granted access via a secure, cloud-based data repository (e.g., Figshare, Zenodo, or a university-managed platform). Data will be provided in standard formats (e.g., .csv, .sav) along with a comprehensive data dictionary and analysis codebook. Agreement: Successful applicants must sign a Data Transfer/Use Agreement (DTUA) legally binding them to the approved use, data security standards, publication ethics (including co-authorship or acknowledgment as per contribution), and destruction of data after the project.

Primary Contact & Communication: All requests for data and documents must be initiated via email to the designated study contact. Contact Person: Ahmadreza Dehghani, Ph.D. in Exercise Physiology Email: adehghani4d@gmail.com/Shiraz University Subject Line: Data Access Request: Pink Noise & Balance Study Secondary Contact (Administrative): For procedural inquiries, a research coordinator can be contacted. Professor Maryam Koushkie Jahromi Email: koushkie53@yahoo.com

Access Timeline: Approved applicants can expect to receive the data files approximately 2 weeks after their proposal is formally approved and the signed data use agreement is returned.

Intellectual Property: Researchers using the shared data are encouraged to collaborate with the original study team. Co-authorship on publications will be offered based on substantial intellectual contribution, as per ICMJE guidelines. All publications must acknowledge the original study and funding source. Costs: There is no fee for accessing the data. However, requestors are responsible for any costs associated with data analysis, secure storage, and their own publication fees. Updates: The shared data will be the final, cleaned version used for the primary publication. Corrections or updates will be versioned and noted in the repository. Ethical Re-Use: Any secondary research using this data must obtain its own ethical approval if required by the researcher’s institution or local regulations.