Review Reports - Association between Physical Activity Levels and Brain Volumes in Adults Visiting Radio-Imaging Center of Tertiary Care Hospital

Round 1

Reviewer 1 Report

The aim of article titled: Association between physical activity levels and brain volumes in adults visiting radio-imaging center of tertiary care hospital was to explore the relationship between physical activity and sedentary behavior on brain volume.

Introduction section include a lot of definitions/expressions rather than an explanation of the reason to conduct the study. The author’s main focus was put on cognitive impairments and Alzheimer’s disease while the main aim was to explore the relationship between physical activity and sedentary behavior on brain volume. What is the link between cognitive function and brain volume? Not much in that matter was discussed.

Also the age of group was very divergent. What was the mean age and SD in the group. Did the authors check what was the mean age in the physical activity categories?

There are fragments of the manuscript that lack relevant references, for example Line 191: “Various observational epidemiological studies have investigated the potential relationship between physical activity and cognitive decline…” from where do the authors state that? No citation included.

There is a lot of studies included concerning cognitive function. It raises up a question: Did the authors check cognitive function of the participants?

There is a lot of abbreviations in the text that were not explained: Line 21-22 in the abstract section, Line 57, 127 in the manuscript. Please explain the abbreviations.

Author Response

Dear reviewer,

We are grateful for the valuable reviews provided by the peer review team. We have made the necessary changes and highlighted the same. We have provided a detailed changes in the table below for your reference

Looking forward to the favourable review

Details of the suggested changes
Association between Physical Activity Levels and Brain Volumes in Adults Visiting Radio-Imaging Center of Tertiary Care Hospital
Reviewer	SL.NO	Suggestions received	Clarifications	Line number
1	1	Introduction section include a lot of definitions/expressions rather than an explanation of the reason to conduct the study. The author’s main focus was put on cognitive impairments and Alzheimer’s disease while the main aim was to explore the relationship between physical activity and sedentary behavior on brain volume. What is the link between cognitive function and brain volume? Not much in that matter was discussed.	The suggested changes has been incorporated	33 - 58
	2	Also the age of group was very divergent. What was the mean age and SD in the group. Did the authors check what was the mean age in the physical activity categories?	The mean age calculations based on the physical activity has been added	Table 1
	3	There are fragments of the manuscript that lack relevant references, for example Line 191: “Various observational epidemiological studies have investigated the potential relationship between physical activity and cognitive decline…” from where do the authors state that? No citation included.	The references has been added and highlighted	Line 181
	4	There is a lot of studies included concerning cognitive function. It raises up a question: Did the authors check cognitive function of the participants?	There was no test were made to assess the cognitive functions since our study aim was to assess the brain regions volume in SB and PA lifestyle. So assessing cognitive functions are out of the scope of this study
	5	There is a lot of abbreviations in the text that were not explained: Line 21-22 in the abstract section, Line 57, 127 in the manuscript. Please explain the abbreviations.	The changes have been highlighted	21-23

Reviewer 2 Report

This is an interesting study that explores the effects of different exercise combinations on the cognitive and physical function. This manuscript is well written and easy to follow. Only a minor revision is suggested to this manuscript.

1. Abstract: the abbreviations such as TIV, GMV, and WMV also should be explained or readers can not unstand; the word "Anecdotal evidence" is suggested to substitute in scientific papers. Besides, the number following the decimal point should be consistent. Please check the whole paper.

2. Introduction: there is a need to add a piece of information on the association between physical activity or fitness and cognitive function (see doi: 10.1186/s12877-022-03564-9) to the Introduction. Further, the hypothesis should be provided after the aim of study.

3. Methods: brain volume may be associated with aging. Why the authors recruited participants with a wide range of ages (18-60 years)? Please provide information about who conducted the test and analyse.

4. Results: there are many formatting errors in Tables such as missing space and the number following the decimal point is inconsistent, so please check the Tables and the whole paper carefully.

5. Discussion: please add a paragraph to explain the possible mechanisms between PA and brain volume.

6. Conclusion: please delete P values from the section.

Author Response

Dear reviewer,

Looking forward to the favourable review

2	1	Abstract: the abbreviations such as TIV, GMV, and WMV also should be explained or readers can not unstand; the word "Anecdotal evidence" is suggested to substitute in scientific papers. Besides, the number following the decimal point should be consistent. Please check the whole paper	The suggested changes has been incorporated	21-23 17
	2	Introduction: there is a need to add a piece of information on the association between physical activity or fitness and cognitive function (see doi: 10.1186/s12877-022-03564-9) to the Introduction. Further, the hypothesis should be provided after the aim of study.	The suggested changes has been incorporated
	3	Methods: brain volume may be associated with aging. Why the authors recruited participants with a wide range of ages (18-60 years)? Please provide information about who conducted the test and analyse	We used a wide age group range to do a sub group analysis. The subgroup analysis will be performed in the future studies and these confounding factors will be included
	4	Results: there are many formatting errors in Tables such as missing space and the number following the decimal point is inconsistent, so please check the Tables and the whole paper carefully.	The suggested changes has been incorporated	Table 2
	5	Discussion: please add a paragraph to explain the possible mechanisms between PA and brain volume	The possible mechanism is explained	183-187
	6	Conclusion: please delete P values from the section	The suggested changes has been incorporated

Reviewer 3 Report

This is a study on the relationship between daily physical activity obtained from questionnaire and brain volume assessed by 1.5T MRI. The thema seems within the scope of this journal and the overall study design and the manuscript seems satisfactory, although several intrinsic limitations should be carefully evaluated.

1. About the cohort of the study.

The number of participants is relatively small with only 13 are categolized in the high physical activity group. The range of age is rather wide from below 20 to 60 years with both sex mixed (as well as both dominant hand, job status etc.), suggesting many potential confounding factors exist in this cohort.

2. left vs right hippocampus.

The data showed left but not right hippocampus showed significant association with physical activity, but data on the right side also showed almost significant level (P=0.079; TPA). left side significancy would be relative and this reviewer advise to mention on this point.

3. abbreviation.

Some are not shown in the manuscript (for example, TPA, PCC)

Author Response

Dear Reviewer,

Looking forward to the favourable review

The number of participants is relatively small with only 13 are categorized in the high physical activity group. The range of age is rather wide from below 20 to 60 years with both sex mixed (as well as both dominant hand, job status etc.), suggesting many potential confounding factors exist in this cohort

We used a wide age group range to do a sub group analysis. The subgroup analysis will be performed in the future studies and these confounding factors will be included

left vs right hippocampus.

To state any value to be statistically significant, the p value has to be less than 0.05 but the right hippocampus value is slightly more than that so we did not emphasis on that but the value has been highlighted

Table 2

abbreviation.

Some are not shown in the manuscript (for example, TPA, PCC)

The suggested changes has been incorporated

Table 2

Round 2

Reviewer 1 Report

Thank you for the corrections.