PONE-D-24-24624A live online exercise program for older adults improves depression and life-space mobility: A mixed-methods pilot randomized controlled trialPLOS ONE

Dear Dr. Phillips,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

As noted by the Reviewers, the manuscript would benefit from the addition of more detail on the methods including the exercise intervention. As this is an RCT, it was reviewed by a statistician who has suggestions for revising the presentation of results. In addition to the comments of the 3 reviewers, I note the following: 1. It would help if a rationale was provided for the 2-month follow-up (i.e., how was this duration chosen?) and if a study objective was included related to this measurement period. Did the authors expect that participants would maintain benefits during the 2 month follow-up? If so, please include this hypothesis. 2. Line 115: "Feasibility measures" is mentioned here, but only one measure is listed in the brackets. 3. Line 125: Please clarify how you determined that participants were "healthy", and why the upper age limit of 80 was chosen. 4. Line 141: Please clarify if all 17 participants participated in the same online class. And over what months did the exercise class take place? I assume it is between Dec 2021 and May 2022, but it would help to clarify the exact timing within the overall study duration. Was the program offered through the university or a local community centre? How many physios/kinesiologists delivered the program? Were they asked any questions about how feasible they thought it was to deliver the program? 5. Please include the demographic outcomes in the methods. 6. Please clarify the PA outcomes in the methods, and provide more details on accelerometer data processing. Did all participants comply fully with the 7-day protocol? Did they record non-wear time? 7. Line 184: The subheading is Life-space mobility in the Results. 8. Line 190: I don't follow the rationale for including nutrition risk as an outcome. Was there a nutrition education component of the intervention that would impact this score? 9. Line 205: Do you know if any of the CON participants started an exercise program during the study period? 10. Line 235: Change to "Descriptive statistics were"11. Please provide more detail on the missing data and multiple imputation. Please clarify if the Figure 1 flowchart in reference 41 was followed prior to multiple imputation. Also, the flow diagram doesn't include the 2-month follow-up. Did all 16 ACTIVE participants return for the 2-month follow-up? 12. Line 263: I don't follow why the one CON participant wasn't excluded prior to randomization since they didn't meet the inclusion criteria. 13. In the figures, I would suggest providing the exact p-values above the plots instead of the "Dissimilar letters"14. Lines 295-296: Based on the values provided here, it seems that both groups demonstrated a decrease in symptoms of anxiety and loneliness - is that correct? If so, please clarify that in the text. Similarly, in Line 301, please clarify that this comparison is relative to the post-intervention timepoint.15. Line 340: How did you know that these 4 participants felt the exercises were too easy? Was there a place in the Zoom poll to enter reasons why they weren't fully satisfied? 16. Line 344: sorry for my confusion, but I thought only 16 participants completed the intervention. How then were there 22 interview participants? Does this include some of the CON participants after they received the intervention? As per the other reviewer's comment, please clarify when the CON participants received the intervention, and if all of them joined one exercise class. 17. Since this was a pilot study, it would be helpful to know how the authors plan to use these findings to inform a future trial, and if the intervention is continuing to be delivered or if there are plans to deliver it more broadly. It would also be helpful to know what the 18. References 6, 24 and 26 are incomplete. 

Please submit your revised manuscript by Oct 28 2024 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Heather Macdonald, Ph.D

Academic Editor

PLOS ONE

Journal requirements:

When submitting your revision, we need you to address these additional requirements.

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and

https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

2. Thank you for stating the following in the Competing Interests section:

“I have read the journal's policy and the authors of this manuscript have the following competing interests: SMP reports grants or research contracts from the US National Dairy Council, Canadian Institutes for Health Research, Dairy Farmers of Canada, Roquette Freres, Ontario Centre of Innovation, Nestle Health Sciences, Myos, National Science and Engineering Research Council and the US NIH during the conduct of the study; personal fees from Nestle Health Sciences, non-financial support from Enhanced Recovery, outside the submitted work. SMP has patents licensed to Exerkine but reports no financial gains from patents or related work.”

Please confirm that this does not alter your adherence to all PLOS ONE policies on sharing data and materials, by including the following statement: "This does not alter our adherence to  PLOS ONE policies on sharing data and materials.” (as detailed online in our guide for authors http://journals.plos.org/plosone/s/competing-interests).  If there are restrictions on sharing of data and/or materials, please state these. Please note that we cannot proceed with consideration of your article until this information has been declared.

Please include your updated Competing Interests statement in your cover letter; we will change the online submission form on your behalf.

3. We note that your Data Availability Statement is currently as follows: [All relevant data are within the manuscript and its Supporting Information files.]

Please confirm at this time whether or not your submission contains all raw data required to replicate the results of your study. Authors must share the “minimal data set” for their submission. PLOS defines the minimal data set to consist of the data required to replicate all study findings reported in the article, as well as related metadata and methods (https://journals.plos.org/plosone/s/data-availability#loc-minimal-data-set-definition).

For example, authors should submit the following data:

- The values behind the means, standard deviations and other measures reported;

- The values used to build graphs;

- The points extracted from images for analysis.

Authors do not need to submit their entire data set if only a portion of the data was used in the reported study.

If your submission does not contain these data, please either upload them as Supporting Information files or deposit them to a stable, public repository and provide us with the relevant URLs, DOIs, or accession numbers. For a list of recommended repositories, please see https://journals.plos.org/plosone/s/recommended-repositories.

If there are ethical or legal restrictions on sharing a de-identified data set, please explain them in detail (e.g., data contain potentially sensitive information, data are owned by a third-party organization, etc.) and who has imposed them (e.g., an ethics committee). Please also provide contact information for a data access committee, ethics committee, or other institutional body to which data requests may be sent. If data are owned by a third party, please indicate how others may request data access.

4. We note that there is identifying data in the Supporting Information file <S2 File>. Due to the inclusion of these potentially identifying data, we have removed this file from your file inventory. Prior to sharing human research participant data, authors should consult with an ethics committee to ensure data are shared in accordance with participant consent and all applicable local laws.

Data sharing should never compromise participant privacy. It is therefore not appropriate to publicly share personally identifiable data on human research participants. The following are examples of data that should not be shared:

-Name, initials, physical address

-Ages more specific than whole numbers

-Internet protocol (IP) address

-Specific dates (birth dates, death dates, examination dates, etc.)

-Contact information such as phone number or email address

-Location data

-ID numbers that seem specific (long numbers, include initials, titled “Hospital ID”) rather than random (small numbers in numerical order)

Data that are not directly identifying may also be inappropriate to share, as in combination they can become identifying. For example, data collected from a small group of participants, vulnerable populations, or private groups should not be shared if they involve indirect identifiers (such as sex, ethnicity, location, etc.) that may risk the identification of study participants.

Additional guidance on preparing raw data for publication can be found in our Data Policy (https://journals.plos.org/plosone/s/data-availability#loc-human-research-participant-data-and-other-sensitive-data) and in the following article: http://www.bmj.com/content/340/bmj.c181.long.

Please remove or anonymize all personal information (<specific identifying information in file to be removed>), ensure that the data shared are in accordance with participant consent, and re-upload a fully anonymized data set. Please note that spreadsheet columns with personal information must be removed and not hidden as all hidden columns will appear in the published file.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Yes

Reviewer #3: Yes

**********

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: No

Reviewer #2: Yes

Reviewer #3: I Don't Know

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: A brief description of the waitlist control is to be provided.

Line 173: Information on the validity of the tool GAI – SF is to be provided.

Line 219: While formal statistical power calculations are often not required for pilot studies, having a calculated sample size can enhance the study's ability to provide useful estimates to effectively inform the design for the main trial or when involved in some statistical analysis.

Line 231: Description of allocation concealment prior to allocation to the groups is to be provided.

Line 241: One-tailed or two-tailed test p-value is to be stated.

Line 241-242: The sentence requires revision.

Table 1: 1 decimal to be provided for the percentages.

Line 271-276, 293-301, 319-322, 326-327: Results are to be presented in table form.

Some data looks skewed. A statement on whether the data are normally distributed and the fulfillment of parametric test(s) assumptions are to be provided.

Line 319, 328: The main table output (test of within/between subjects) from the two-way repeated measure ANOVA analysis is to be included.

Line 350: From the qualitative study, the number of participants who took part in the discussion from the list of n=22 is to be mentioned.

In one-to-one interviews in qualitative studies, if no new themes emerge and existing themes are exhausted, will the interview stop even if the sample size has been met?

Reviewer #2: Robust PhD study and very well written.

I have suggestions that might help with understanding, replication, or translation into practice.

I would like to see more about what the intervention actually was. Especially since the intervention was described by authors as 'progressive' and participants mentioned the intervention 'offered options' but some participants also rated the exercises 'too easy.'

Was any equipment/household items used/needed for programme. Could you describe the progressive technique used? How could this programme be improved (if at all) for a full RCT? What could we learn from this study (from a practitioners view)?

Were all 17 participants in the same zoom class? Again, was this feasible, or recommended for future online classes? Did it hold some more advanced participants back (hence the 'too easy' rating)?

Participants are described as healthy. Do you have data on how many health conditions the participants had on average?

Reviewer #3: General feedback:

This is a mixed-methods pilot randomized controlled trial of N=32 participants, comparing the preliminary effectiveness of a live, online exercise program for older adults compared to a waitlist control group. The primary outcome was physical activity levels as measured by accelerometery. Overall, this is a well-designed study with clear and compelling writing. The authors demonstrated that this was a feasible program with high degree of program attendance and participant satisfaction. Although underpowered to detect differences the authors report improvements in depression and life-space mobility and bolster these findings with qualitative support.

Some limitations of the study include the use of a waitlist control vs. an attention control. Something is often better than nothing in exercise trials and it is not possible to understand if contextual factors are driving improvements vs. the exercise program itself.

Further, the online exercise intervention is not well reported. The authors describe 3x60 min of online exercise classes delivered via Zoom, 5 min warmup/cool down, 50 min of progressive strength, aerobic, and balance training focusing on functional movements. There are several important elements missing here such as: the actual exercises performed in each of the categories, exercise dosage (i.e. reps/sets/ RPE based?), decision rules for how exercises were progressed, use of exercise equipment etc. I would recommend referring to the CERT guidelines (consensus on exercise reporting template): https://bjsm.bmj.com/content/50/23/1428

Another limitation is that the primary outcome measure of “habitual physical activity” is not clearly defined in the methods- i.e. it is discussed that it will be measured using accelerometery, but it is not clear what exact metric you are considering your primary outcome i.e. daily steps vs. daily active energy expenditure.

Lastly, the qualitative analysis lacks sufficient detail in reporting which decreases confidence in the rigour of this aspect of the study.

Strengths:

-well-designed study

-compelling and clear writing

Limitations:

-online exercise is not well reported

-main outcome measure of “habitual physical activity” is not defined in methods.

-some challenges with qualitative analysis reporting

-blinding not possible (acknowledged in limitations)

-small sample size (acknowledged in limitations)

Line by line feedback:

Line 96: “ability-modified, low-risk exercise program”- this is the only time the exercise program is described in this way. What makes an exercise program high vs. low risk? Typically exercise interventions delivered by physiotherapists are described as “individually tailored” and parameters for how exercises were regressed or progressed are described.

Line 205: “All participants (ACTIVE and CON) who completed the online exercise program were invited via email to participate in an optional one-on-one 30-minute qualitative interview, regardless of group allocation.” I think it would be helpful to mention a bit more about the waitlist control group- when were these individuals invited to take part in the intervention? I don’t think it is mentioned prior to this statement.

Line 207: Indicate whether these were 1:1 interviews. Also did every participant in the trial participate in an interview? If not, perhaps state a “sub-sample of participants”.

Line 247: Your description of the qualitative analysis should include a reference for thematic analysis. Also, the analysis process is not clear… It appears that the first step was creating an initial codebook based on pre-specified topics of interest (deductive approach)- but the next sentence states that the coders met to discuss new codes identified and code the remaining transcripts. Were the first few interviews coded together, where the pre-specified topics and the data itself was used to create the initial codebook? If so, this should be specified and should clearly indicate the combination of deductive and inductive approaches. How did the coders ensure consistency between their interpretation i.e. intercoder reliability?

Line 252-256: This sentence is a bit confusing- by introducing the sentence with “this iterative process”, I assume you are talking about coding, but you are introducing the creation of themes and sub-themes. Revise to increase clarity and include a description of how the codes were crystalized into their preliminary and final themes.

Line 255: - “the themes and sub-themes were those most commonly cited in the data”- did the authors use actual code counts to derive themes and sub-themes?

Another point to address in your description of the qualitative analysis is how the interview guides were created and whether they were they piloted with participants?

Line 360: “The qualitative data refute our quantitative findings”… I think this statement is a bit too strong as the quantitative data lacks sufficient power to detect an effect with any certainty.

Line 379: I think you need to define what “growing old gracefully” means here.

**********

6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

Reviewer #3: No

**********

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

A live online exercise program for older adults improves depression and life-space mobility: A mixed-methods pilot randomized controlled trial

PONE-D-24-24624R1

Dear Dr. Phillips,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Heather Macdonald, Ph.D

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Thank you for addressing my queries. 

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #3: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: (No Response)

Reviewer #3: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: (No Response)

Reviewer #3: I Don't Know

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: (No Response)

Reviewer #3: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: (No Response)

Reviewer #3: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: (No Response)

Reviewer #3: (No Response)

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #3: No

**********