Strength and Balance Integration in Maintenance Cardiac Rehabilitation for Older Adults

Study Design: This will be a pilot cluster RCT. The control group participants will remain in traditional aerobics-based cardiac rehabilitation. The intervention group participants will undergo additional strength and balance exercises within their cardiac rehabilitation classes).

Location: All classes will occur in their current venues (community). Baseline and follow-up functional fitness tests and questionnaires will take place in these same venues. Focus-groups (participants in the Intervention Group) and interviews (exercise leaders) will take place online using Microsoft Teams.

Length of time participants will be involved in the study:

Participants in Cardiac Rehabilitation Groups - 30/40-minute appointment (at their normal venue for their classes) in February/March 2026 for Functional Fitness testing, 12-week follow up testing and 60-90-minute focus group online appointment in June 2026. Exercise Leaders (Intervention Group) will be interviewed at the end of the study (maximum 60 minutes).

Participants: The study population will be older adults aged 50+ in Scotland attending Community/Maintenance Cardiac Rehabilitation classes.

Interventions: Control arm: participants will continue with their traditional cardiac rehabilitation classes in the same form (usual care).

Intervention arm: Exercise Leaders will add strength and balance exercises into the session (approximately 20 minutes in each 60 minute class) for the 12 weeks of the study. Instructors will be provided with a video showing a variety of potential exercises they could add into their class (approximately 10 strength and 10 balance exercises (dynamic and static). It is their discretion which exercises they put into their classes and can alter them within the selection between classes, allowing them to tailor to their particular group abilities. The exercises have been chosen as they have been added, without any adverse events, to 5 classes in the local area courtesy of one instructor who found her clients needed more strength and balance work in their sessions to improve their stability during the endurance work. Anecdotally, most participants fed back to the instructor that these exercises had helped their balance and stability.

Primary Outcome Measures:

Two functional fitness tests from the Functional Fitness MOT (FFMOT) (see below) that assess lower body strength and balance (the 30-second chair stand test and single leg balance).

The secondary outcome measures are: The remaining 4 FFMOT measures, a modified version of the Rapid Assessment of Physical Activity (RAPA), confidence in balance (CONFBal) and the Falls Efficacy Scale - International (FES-I). The three questionnaires are validated.

Functional Fitness MOT - the functional tests within the FFMOT are all validated functional tests with normative data (for age and sex).

1. 30-Second Chair Stand as a measure of lower limb strength; 2. Handgrip strength as a measure of upper limb strength; 3. Single Leg Stance as a measure of static standing balance; 4. 8 Foot Up and Go as a measure of dynamic balance and mobility; 5. The Chair sit and Reach as a measure of lower limb flexibility and 6. Back Scratch as a measure of upper limb flexibility. Flexibility tests (5 and 6) have been added as strength training has been found to cause muscle stiffness. The final test in the FFMOT - the 6-Minute Walk Test will not be used in this study as it is a measure of lower limb endurance and often captured by cardiac rehabilitation programmes already.

Feedback on the functional tests above will be provided on performance in comparison to normative age-and-sex-appropriate data.

Qualitative data: as part of a process evaluation investigators will capture participants' perceptions, understanding and views of having strength and balance exercise added to Maintenance Cardiac Rehabilitation sessions via focus groups of 6-8 participants, as recommended. This will be completed within two weeks following the 12-week follow-up. The investigators will host these focus groups online to reduce travel burden and time for participants and researchers. The investigators appreciate this will mean potentially excluding views of anyone who is not comfortable in using Microsoft Teams. Investigators will ask people who might want to express their views to talk to their Exercise Leader and they can share with the investigators any views not captured from those willing to join our online groups. Investigators aim to run one focus group per Intervention Group class so not all participants will be expected to be involved in this aspect of data collection.

All consenting Exercise Instructors leading the Intervention Groups will be interviewed on Teams about their experience, views and understanding of adding strength and balance exercise to their Maintenance Cardiac Rehabilitation sessions.

Data Handling \& Record Keeping:

Data will be collected and be accessible to the immediate study team only. FFMOT's will be undertaken by DPT student Areeba Iqbal, Professor Dawn A Skelton and Dr Morag Thow. All members of the study team have received appropriate training from Professor Dawn A Skelton to carry out the FFMOT.

In addition to the data collection mentioned above, rates of recruitment (within current cardiac rehabilitation sessions, as not all will consent) and data loss (anyone that leaves or does not complete 12 week follow-up) will be reported. Retention (attendance data at the sessions) will be reported.

Furthermore, demographics will be reported (age, sex, location of screening, number of months/years engaged in current cardiac rehabilitation classes and attendance at exercise sessions during the 12 week study. Participants' household postcode will be categorised in terms of the Scottish Index of Multiple Deprivation. All the data from the participants will be anonymised and follow General Data Protection Regulations.

Focus groups and interviews will be recorded on Microsoft Teams to obtain key quotes supporting themes. The Teams transcriptions will be downloaded, anonymised and saved on an encrypted drive and then the recordings on Teams will be deleted.

As soon as participants are recruited into the study, they will be assigned a unique number by the PI.

The data file giving the names of the participants and unique numbers will be stored in a secure cloud-based system hosted by GCU. Thereafter, all data collected will use these unique identifiers, so that the data is kept anonymous. The PI will collect and record all data from baseline, follow-up, and focus-group assessments via paper-based data collection. These will be scanned and put into digital formats (original paper form destroyed) and then stored in a secure cloud-based system hosted by GCU. Fully anonymised data will be manually entered into Microsoft Excel by the PI. Following completion of the study, all such data will be archived in line with GCU procedures and confidentially disposed of after 25 years (new regulations for Clinical Trial Data from 2026, from recent Good Clinical Practice Training).

Data Analysis:

Initially, the quantitative OMs (see above) will be checked for normal distribution using SPSS software. If the data is normally distributed, then the data will be presented as means (± SD) at baseline and post-intervention, and an ANOVA will be performed to determine any group differences. If the data is non-normally distributed, data will be presented as Median (range), and the Wilcoxon-Mann-Whitney test will be used to look at differences over time within groups. Effect sizes, using Cohen's ds of within-group changes, will provide information to help determine sample size in subsequent studies.

A Word document will be shared online by the researcher during the focus group to confirm, review, and validate general themes with participants in real time, enabling a naturalistic view in the group setting.

Interviews with the Exercise Leaders will also take place on Teams and be transcribed and thematically analysed taking an inductive approach. Anonymised transcripts will be read through independently by three researchers several times to familiarise themselves with the data and to identify candidate themes using open coding and listing codes under higher order headings. To enhance trustworthiness and credibility and to refine the final themes, an additional fourth researcher will review.

The study will adhere to GCU data security and data protection/GDPR legislation.

Recruitment of Participants and Consent: As this is a pilot cluster RCT the investigators have not performed a sample size calculation and instead look to recruit from a convenience sample of participants from six traditional aerobic-based Community/Maintenance Cardiac Rehabilitation Classes. Investigators have already spoken to the Exercise Leaders of these sessions (as Gatekeepers), and they will invite the PI, who will then introduce the study to potential participants and answer any questions.

Potential participants will be mailed a participant information sheet by the PI explaining the research and a consent form to complete if they are interested in taking part. They will return these to their Exercise Leader, who will send them to the PI. They will be informed that their participation is voluntary and their attendance at the Maintenance Cardiac Rehabilitation classes will not be affected if they choose not to participate. The PI will then contact them by telephone and screen them based on the inclusion and exclusion criteria and answer any questions the participant has. Participants will be invited to their Community Maintenance Cardiac Rehabilitation class premises at a time that suits them to undertake baseline data collection.

The traditional aerobic-based Community/Maintenance Cardiac Rehabilitation class venues (clusters) will be randomised (rather than the individuals recruited within the classes) to avoid contamination. Once the PI has received all consent forms and performed the screening, the names of the traditional aerobic-based Community/Maintenance Cardiac Rehabilitation classes (there are six across Scotland that have agreed to be recruited) will be sent to an independent researcher (Janet Finlayson) who will randomise the groups using https://www.randomizer.org/. Following this, they will let the PI know which classes (and individuals within those classes that have consented to be involved in the study) will have an additional strength and balance exercises added (Intervention), and which classes will continue as usual (Control). Following randomisation of the groups, the groups will carry out their intervention for 12 weeks. They will then be invited to their Community/Maintenance Cardiac Rehabilitation class premises at a time that suits them to complete follow-up testing within two weeks of completion of the 12 week intervention. The intervention group participants will be invited to take part in online focus groups two weeks after their testing. Participants will be told they can withdraw from the study up until the analysis/study write-up. After this point data will be pooled together; therefore, it will not be possible to segregate individual data. Participants will be told that this will not affect their participation in their Community/Maintenance Cardiac Rehabilitation class sessions. If any participants in the Intervention Group would prefer not to undertake additional strength and balance exercises the Exercise Leader will give them traditional aerobic exercises to complete whilst the others do the additional strength and balance exercises.

Exercise instructors/physiotherapists will be recruited at the start of the study. Potential participants will be mailed a participant information sheet by the PI explaining the research and a consent form to complete if they are interested in taking part. They will send these to the PI. They will be informed that their participation is voluntary, and their

• Hand-held Dynamometer / Grip Strength [Time frame: Baseline and 12 weeks]
• 8-Foot Timed Up and Go [Time frame: Baseline and 12 weeks]
• Chair Sit and Reach [Time frame: Baseline and 12 weeks]
• Apley's Back Scratch Test [Time frame: Baseline and 12 weeks]
• Rapid Assessment of Physical Activity [Time frame: Baseline and 12 weeks]
• Confidence in Balance [Time frame: Baseline and 12 weeks]
• Falls Efficacy Scale - International [Time frame: Baseline and 12 weeks]