PONE-D-21-29548The Impact of Skeletal Muscle Disuse on Distinct Echo Intensity Bands: A Retrospective AnalysisPLOS ONE

Dear Dr. Stock,

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Reviewers' comments:

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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: Yes

Reviewer #2: Yes

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

Reviewer #1: Yes

Reviewer #2: Yes

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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

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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

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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: In this retrospective study, the Authors aimed at exploring whether the increase in ultrasound-derived echo intensity (EI) following two weeks of knee joint immobilization was limited to specific bands of the EI histogram.

Generally, this manuscript is well written and contributes to deepening our understanding of muscle quality by means of ultrasound technique and image analysis.

I have few more suggestions to improve the manuscript quality.

L18. I don’t think this sentence is completely correct. EI is measured from ultrasound. I suggest stating something like “… EI can be assessed quickly from ultrasound scans”.

L18-22. This is true if ImageJ is used as a software for the analysis. This should be acknowledged.

L103-106. Please, provide further details about the technique used for EFOV images acquisition.

L189. At this point of the manuscript there is no need to state that a difference is “significant”. I suggest erasing it.

L201. I am not a native English speaker, so consider this suggestion only if it is correct: “… the work by Pinto and Pinto..”

L209. Can you make a speculation about it?

L229. Same as at L201.

L245. Same as at L201.

Reviewer #2: The present manuscript aimed to investigate changes in muscle quality after two weeks of lower limb immobilization comparing the traditional EI mean with EI bands approach. The paper is well written and the methodological research question is of interest.

I only have some minor concerns that need to be addressed:

Abstract

I think your abstract conclusion should highlight also the comparison between 25 and 50 band intervals.

In the last sentence of the abstract, please specify that you are referring specifically to EI mean, otherwise this sentence could be misinterpreted (as EI is not robust in general)

L46-48: have you tried to carry out the correlation between VL CSA changes and EI in the different bands?

L209: Could you add at least some speculation on the potential physiological reasons?

L233: Why did you limit your analysis to VL? From Figure 2 the rectus femoris (RF) seems to be fully visible. I think that a comparison between VL and RF would be a nice addition to this work, considering that RF (being multi-joint) is generally less affected by disuse compared to the VL.

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Reviewer #1: No

Reviewer #2: No

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The Impact of Skeletal Muscle Disuse on Distinct Echo Intensity Bands: A Retrospective Analysis

PONE-D-21-29548R1

Dear Dr. Stock,

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.

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Kind regards,

Emiliano Cè

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

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

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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: Yes

**********

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

Reviewer #1: Yes

**********

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: 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: 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: The Authors have successfully addressed all my comments and concerns. I do believe that the manuscript has improved.

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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