The Effect of 6-Month Complex Exercise on Serum Bone Metabolism: Focused on the Elderly over 75 Years Old

Round 1

Reviewer 1 Report

Basic reporting

The study assessed the effects of exercise on serum osteocalcin, bone ALP, and estradiol after six months of complex exercise. In general, this study aims at an important thematic and the one that is of largely interest considering the beneficial impact of physical activities. Whilst the study undoubtedly has merit, many aspects need clarification, to improve the readability of the manuscript.

ABSTRACT

Key words

Please, do not repeat key words that appear in the title.

INTRODUCTION

General comment: The first issue is the novelty. What is the novelty of this study? Research in most studies that the authors provide in the discussion section has shown physical activity for the elderly age. Thus the authors have to find some points that their study provides something new to the literature (and highlight them) and also search deeper into the literature.

MATERIAL AND METHODS

Participants

1)      I suggest you improve the description of the sample selection. How have you chosen this sample of the elderly?  How groups were distributed?

2)      Please, could you deeply present the demographic data of the sample? Where are they from? Which region of Korea? From a rural or urban area? How many men and how many women?

3)      Please, could you deeply present how you proceed to select your sample? 
It is a representative sample? If is it, introduce please the Sample size calculation

Measurements

Please present information about how and where the exercise sessions were performed and who conducted the sessions. Please detail in a paragraph all the main information and the necessary details in order to provide the reader a clear picture of how were performed.

Moreover, you should explain the exact training (which exercises) and detail the parameters (volume, intensity, rest time, etc.). I suggest you add a graphical figure to summarize it.

Line 116: Why 11-14 RPE? Please explained and support it with appropriate references.

Statistical analyses

Did you check the sample normality? If so, please add the procedure.

Please, calculate and report the effect size’s values.

RESULTS

General comment: Delate ‘ANOVA’ in the subheadings.

Figures: Consider using individual figures in order to show each pre- post- change.

Tables: Please add effect sizes’ values.

DISCUSSION

Please, start this section with the main purpose of the study and the main finding.

In the discussion, the authors should be more specific to answer the study's aim and address the main results.

I suggest you to included several considerations about the limitation of your study.

CONCLUSIONS

The conclusion section is too long and should be rewritten. Moreover, a practical implications section should be included. How these findings can help public health? Which practical implications can it have in training sessions? 

Moreover, this section should not contain references.

Author Response

Thank you for your careful review. 
I supplemented contents in the introduction and discussion section, and changed the inconsistent and contradictory contents again.
Also, please check the paper again as I have revised the paper to make the results easier for readers to understand

Please check the attached file

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments:

This study analyzed the effect of exercise on bone formation indicators (serum osteocalcin, bone ALP, and estradiol) through complex exercise training in elderly people aged 75 years and over for 6 months. The authors argued that although there were no significant differences in osteocalcin, ALP, and estradiol, positive improvements appeared in the exercise group, and regular exercise played a positive role in improving bone mineral density in the elderly. Although this research is an interesting subject in the field of health promotion and exercise physiology in the elderly, there are some problems as follows. I am honored to have the opportunity to judge interesting and valuable research.

Abstract

1. L25~28: Abstract conclusion is made based on the results obtained through this paper, but it would be good to add content that you would like to propose to future research. For example “In the future, it will be useful to maintain and improve the health related to the skeleton of the elderly through the combined participation of aerobic, resistance, and balance exercises, and it is necessary to increase the intensity and frequency.”

2. L24: Estradiol in the control group appears to have decreased. It should be corrected to “decreased” instead of “increased”.

3. L29: I think it would be better to add estradiol to the keywords.

Introduction

Major

1. It seems that the explanation of why osteoporosis is dangerous for the elderly should be added, and the decrease in variables that appear due to this or the association with bone metabolism-related variables should be highlighted. I also think it would be nice to add the seriousness of the problem of osteoporosis that appears in older people.

Minor

1. Consistency in numbering of references should be maintained. For example, ~ be required till 2040[9] is written of not spaces, and others are separated of spaces the "~ body part [11]". Be consistent throughout your content.

2. L65: walking[17, 18] -> [17,18] The spaces between numbers should be removed.

Materials and Methods / Results

1. A body composition test and a bone density test were performed. Physical characteristics include only age, height, and weight, and do not provide result values for the remaining measured variables (bone density, %body fat(%), fat mass(kg), BMI).

An item should be removed if it does not provide a result value.

2. I think it would be good to explain the exercise program in a little more detail or present it in a table or diagram. Aerobic exercise is a bicycle and running machine, resistance exercise is what part, and balance is what kind of exercise?

3. The statistical method used in this study is misrepresented. In this study, Repeated Two-way ANOVA analysis with 2X2 must be performed to confirm the effects of group and time. You should also perform a dependent t-test if there is a main effect of time in the post hoc analysis, and an independent t-test if there is a main effect of group.

4. Tables 2 and 3 can be seen as the results of the statistical analysis. Repeated Two-way ANOVA results for the Osteocalcin, ALP, and estradiol variables should be presented, respectively.

Discussion

1. In the discussion of this study, it was reported that estradiol levels decreased or showed low levels as people aged, and that exercise improved these estradiol levels. However, estradiol decreased in all populations and less in the exercise population than in the control population. It seems that the discussion related to this should be revised a little.

- It is judged that it would be good to add content such as "exercise is judged to be able to delay the decrease in estradiol levels due to aging."

- L248: Estradiol in the control group appears to have decreased. It should be corrected to “decreased” instead of “increased”.

2. References used in the text should include only surnames and abbreviations of names should be deleted. This should be corrected.

- L212: For example, Smith MZ et al (2008)[38] -> Smith et al.[38]

In addition, the incorrect reference and notation in the text should be corrected.

L225, L229, L234, L239, L250, L265

Conclusion

1. Although part L272-277 of the conclusion deals with the need for physical activity in the elderly, it seems better to address the problem of osteoporosis, a problem that appears in the elderly in this study. After that, I think it would be good if the content of the exercise program implemented in this study showed what kind of results and how it would be used in the future.

2. Additionally, limitations of this research and suggestions for future research should be added.

3. L277: previous literature -> Please remove this phrase.

References

The bibliography is inconsistent, with some having the surname first and others having the given name first.

Please modify the text and references according to the academic journal reference form.

Comments for author File: Comments.pdf

Author Response

Thank you for your careful review. 
I supplemented contents in the introduction and discussion section, and changed the inconsistent and contradictory contents again.
Also, please check the paper again as I have revised the paper to make the results easier for readers to understand

Please check the attached file

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors were concerned with improving the work through suggestions, which greatly increased the quality of the article. However, there are some issues that should be improved to increase the manuscript quality:

1) I understand your explanation about the number of participants, but please, introduce the Sample size calculation. I suggest using G-Power software or similar.

2) Why do you refereeing a 11-14 RM, as an anaerobic exercise? Maybe you are referring as a Resistance training?

Author Response

Thank you for your careful review. 

1) I understand your explanation about the number of participants, but please, introduce the Sample size calculation. I suggest using G-Power software or similar.
As a result of using G -power as a standard, the total sample size is 24 people.

2) Why do you refereeing a 11-14 RM, as an anaerobic exercise? Maybe you are referring as a Resistance training?
Yes, it's Resistance training.
Fixed the wrong word entirely.

Author Response File: Author Response.docx