Review Reports - The Impact of Isolation Due to COVID-19 on Physical Activity Levels in Adult Students

Round 1

Reviewer 1 Report

My primary concern with this manuscript is the alignment with the aims and scope of Sustainability. In the opening line of the aims of the journal, the following is mentioned: …journal of environmental, cultural, economic and social sustainability of human beings, which provides an advanced forum for studies related to sustainability and sustainable development. I see no alignment with this aim in the current manuscript. Further, ‘physical activity’ or any similar keywords are not mentioned in the subject areas that Sustainability supports. In looking at other manuscripts that have been published by Sustainability, I cannot see how the current manuscript would appeal to the readership of this journal.

That being said, I do think this is worthy and publishable research and I commend the authors for having the foresight to collect and report upon these data during a pivotal time in the world. I would be happy (and eager, really) to review this manuscript for a more appropriate and aligned journal. If the authors choose to stay with the MDPI group of journals, I would strongly suggest International Journal of Environmental and Public Health (there are many articles relating to physical activity that have been successfully published in this journal) or Sports.

Author Response

Firstly, the authors would like to thank the anonymous reviewers for their time, effort and insightful comments that have significantly improved the quality of the proposed manuscript. Revisions and modifications have been highlighted.

Thank you for your comment. Authors agree with the reviewer that general Journal's scope is within environmental, cultural, economic and social sustainability of human beings. However, this manuscript have been submitted to the special issue section with the title of "University Education in the Age of COVID-19: Transformations and Challenges for Students and Teachers". According to the aim of this special issue we developed our manuscript directly for this Journal as a first choose. Please consult the special issue information here: https://www.mdpi.com/journal/sustainability/special_issues/uni_edu_sus

A series of changes were also introduced to the article, referring to journal's scope. We hope that the new version of the article will minimize this feeling

Reviewer 2 Report

Thank you for giving me the opportunity to review paper The Impact of Isolation due to COVID-19 on Physical Activity Levels in Adult Students. The purpose of the study was to compare the level of physical activity during the restrictions introduced during the Covid-19 pandemic and to determine how the implementation of the "unfreezing" stage of sport and recreation affected the physical activity of young adult people. Paper taking relevant research problem for the public health and sport sciences. The current global situation related to the COVID-19 pandemic is associated with many negative consequences for societies. Many of them will show up in the future, so it is important to conduct multi-faceted research to diagnose potential negative effects and propose how to solve new problems. The purpose of the review manuscript fits in with this task.

Broad comments

The title is appropriate for the content of the article. The abstract is concise and accurately summarizes the essential information of the paper, but it must be supplemented with the purpose of research. Paper's structure is not correct and needs improvement. In the introduction, the epidemiological situation in the country where the research was conducted was correctly outlined. However, the introduction contains mostly well-known statements. Today there is no need to write about the relationship between physical activity and health. Rather, I would expect the review the literature in the introduction and locate their own research on this background. There is a lack of any justification for the research undertaken. It needs to be supplemented. Sections: 2.1. Participants; 2.2 Outcome measure; 2.4. Statistical Methods; 3. Results have been written correctly. 2.3 Scoring Protocol: IPAQ is a well-known tool, so there was no need to describe it in detail. An overall good discussion of the results.

Several concerns are brought up when reviewing this manuscript. In my opinion, there are major issues that limit the scientific and practical relevance of the results obtained in the present study. First of all, the conclusions were incorrectly formulated. The conclusion does not result from the conducted research. Based on these studies, it cannot be concluded that The study results show that the lockdown influenced negatively on the level of physical activity among the subjects (lines: 224-225). To make such a conclusion, research should be carried out before and during the pandemic, as did the authors cited in the text (Srivastav et al. 2020; Giustiono et al. 2020; Castañeda-Babarro et al. 2020). However, the authors can only conclude that "unfreezing" the restrictions resulted in an increase in physical activity. The restrictions were introduced precisely to limit people's mobility, and consequently physical activity. For example, the conclusion may be that the government's actions have been effective. Here are some comments that will hopefully help you improve the paper:

The novelty of the study: What did the authors want to show? Did the authors want to show that the restrictions introduced were effective? What is the new discovery?
The relevance of the findings: I believe that this particular study does not have a great deal of practical impact. How did the authors to expect as a specific practical application?

Specific comments

The abstract needs to be supplemented with the purpose of the research.
Introduction. The introduction needs a bit stronger rationale for the study conduct as do we not already know all this or why is it important to know? This section should also include a literature review.
I suggest describing the studied group of students in more detail. There should be information about the type of university and the field of study. If these are students studying at a sports college, this information is important in the context of the results obtained.
Also, my doubts concern the test used to assess the significance of differences in the level of physical activity. Why was non-parametric test chosen? Please also add information on Shapiro-Wilk test, skewness and kurtosis.
Lines 127-128: “The analysis of the value of total energy expenditure showed a statistically 127 significant difference between lockdown and "unfreezing” periods (p<0.029).” Is this the result for all participants? Are the differences significant in men and women?
Line 138: Figure 1. Please explain the abbreviations Part 1, Part 2…, also „0” and „1”.
Lines 224-225: I suggest changing the conclusion because it does not result from the conducted research.

Author Response

Thank you for your valuable comment. The aim of the study was to assess changes in the level of physical activity during the lockdown and in the "unfreezing" stage in Polish students. A practical aspect of the research was an attempt to emphasize the lack of adequate amount of physical activity which in consequence may lead to impairment of health. Since the future of the epidemic is unclear, it is important in this context to provide an education based on health promotion using various forms of activity depending on the restrictions introduced by the government. This approach has been further developed in the introduction.

Sections: 2.1. Participants; 2.2 Outcome measure; 2.4. Statistical Methods; 3. Results have been written correctly. 2.3 Scoring Protocol: IPAQ is a well-known tool, so there was no need to describe it in detail. An overall good discussion of the results.

In this study a long version of the IPAQ questionnaire was applied. We noticed that the short form is used more often in research. Due to this fact we decided to leave a short description of the examined parts.

Several concerns are brought up when reviewing this manuscript. In my opinion, there are major issues that limit the scientific and practical relevance of the results obtained in the present study. First of all, the conclusions were incorrectly formulated. The conclusion does not result from the conducted research. Based on these studies, it cannot be concluded that The study results show that the lockdown influenced negatively on the level of physical activity among the subjects (lines: 224-225). To make such a conclusion, research should be carried out before and during the pandemic, as did the authors cited in the text (Srivastav et al. 2020; Giustiono et al. 2020; Castañeda-Babarro et al. 2020). However, the authors can only conclude that "unfreezing" the restrictions resulted in an increase in physical activity. The restrictions were introduced precisely to limit people's mobility, and consequently physical activity. For example, the conclusion may be that the government's actions have been effective. Here are some comments that will hopefully help you improve the paper:

The novelty of the study: What did the authors want to show? Did the authors want to show that the restrictions introduced were effective? What is the new discovery?
The relevance of the findings: I believe that this particular study does not have a great deal of practical impact. How did the authors to expect as a specific practical application?

Thank you for your comment. The results of the study were reformulated to be consistent with the purpose of the research. The presented research is a first step of a wider concept. Currently we are in the process of obtaining data evaluating the quality of life of students during remote learning and temporary movement restrictions. Considering the results from both studies we want to develop guidelines regarding the type of activity, duration and intensity, likewise how to manage stress through e.g. breathing exercises among students to increase their psychosomatic potential in similar situations as during a pandemic. We want to promote health education through social media, which are used in the transmission of information by students.

Specific comments

3. The abstract needs to be supplemented with the purpose of the research.

The abstract was supplemented by the findings related to the purpose of the study.

4. Introduction. The introduction needs a bit stronger rationale for the study conduct as do we not already know all this or why is it important to know? This section should also include a literature review.

The introduction was supplemented with detailed information on the impact of short-term physical inactivity on health.Moreover, the introduction of well-known information concerning the relationship between movement and health was abandoned.

5. I suggest describing the studied group of students in more detail. There should be information about the type of university and the field of study. If these are students studying at a sports college, this information is important in the context of the results obtained.

Thank you for your concern. The data was completed in section 2.1 Participants

6. Also, my doubts concern the test used to assess the significance of differences in the level of physical activity. Why was non-parametric test chosen? Please also add information on Shapiro-Wilk test, skewness and kurtosis.

Thank you for this question. We assumed the critical value for 90 participants, obtained from distribution tables W. The W value for 90 participants with p< 0.5 is 0.962. Each value achieved was lower than the critical value, which suggests that the distribution of the analyzed variable is different from normal distribution. The following results were obtained for individual parts of IPAQ: Part 1: 0.518; Part 2: 0.757; Part 3: 0.732; Part 4: 0.886; Total: 0.712; Sitting: 0.930.

7. Lines 127-128: “The analysis of the value of total energy expenditure showed a statistically 127 significant difference between lockdown and "unfreezing” periods (p<0.029).” Is this the result for all participants? Are the differences significant in men and women?

Thank your for pointing this out. The indicated p-value refers to all participants. We have removed gender-specific value information to maintain a common description of the results.

8. Line 138: Figure 1. Please explain the abbreviations Part 1, Part 2…, also „0” and „1”.

Thank your for pointing this out. The term "Part" referred to the IPAQ category, the figure has been completed with the consistent terms in Table 1 and Chapter 2.2 Outcome measure

9. Lines 224-225: I suggest changing the conclusion because it does not result from the conducted research.

After the improvements made in the manuscript, in our opinion, the conclusions are now consistent with the aim and hypothesis of the research

Reviewer 3 Report

The Impact of Isolation due to COVID-19 on Physical Activity Levels in Adult Students

The topic has great actuality. The study is nicely executed using the long form of IPAQ. I have no serious objections to the study and the conclusions You reach. I could have wanted some more, and wider, discussions about physical activity/inactivity and health. Not only from studies during the pandemic, but also from more “natural” settings. Some “clasics” is suggested in my comment file. You could also discuss in more details the differences between the long and short form of IPAQ, and how that might influence the results. You used a convenience sample, so You should also discuss this when presenting the results - and differences to other studies. I have also taken the liberty of suggesting some changes in the wordings around in the manuscript. Theses are suggestions, and You are free to use them or not.

Comments for author File: Comments.pdf

Author Response

The information provided in the introduction on the overall impact of physical activity on health has been changed, thus we have not used the references indicated. Considering the comments of all the reviewers, we came to the conclusion that it would be more appropriate to describe the effects of short-term physical inactivity on health.

You could also discuss in more details the differences between the long and short form of IPAQ, and how that might influence the results.

Thank your for pointing this out. In the discussion we briefly indicated the differences between the long and short versions of the IPAQ questionnaire. We would like to mention that in the study we used the long version due to the fact that it is much more extensive and detailed. It gives a lot of precise information about specific types of physical activity, e.g. time spent on cycling, walking in leisure time, or gardening. Another important aspect is the possibility of analyzing the time spent on sitting in the long version of IPAQ. In the long version, this issue includes the question of the amount of time spent on sitting in leisure time, which is missing in the short version.

You used a convenience sample, so You should also discuss this when presenting the results - and differences to other studies. I have also taken the liberty of suggesting some changes in the wordings around in the manuscript. Theses are suggestions, and You are free to use them or not.

Thank you very much for the valuable editorial tips which we used in the manuscript to improve the content. We have also made changes to the manuscript according to the indicated feedback.

We used non-parametric test based on Shapiro-Wilk test. We assumed the critical value for 90 participants, obtained from distribution tables W. The W value for 90 participants with p< 0.5 is 0.962. Each value achieved was lower than the critical value, which suggests that the distribution of the analyzed variable is different from normal distribution. The following results were obtained for individual parts of IPAQ: Part 1: 0.518; Part 2: 0.757; Part 3: 0.732; Part 4: 0.886; Total: 0.712; Sitting: 0.930.

Round 2

Reviewer 1 Report

I thank the authors for pointing out that the manuscript was submitted as part of a special edition of IJERPH. As such, I think that while slightly still misaligned, the improvements the authors have made now fit within the scope of the special edition.

As I have recommended in the report, extensive editing of English language and style is required. For instance, there are multiple errors in the abstract alone (line 23-24).

I would suggest using the abbreviation of PA for physical activity throughout.

Line 49: the word “a” in front of “large-scale” is not needed

Lines 52-53: Can the authors please expand on why/what specific restrictions imposed barriers on outdoor activities?

Lines 56-57: This sentence is repetitive (see lines 52-53). Suggest removing.

Line 59: Not sure what the “ref” is needed for

Line 67: “do” should be “does” and “this” should be “these”

Line 68: “need” should be “needs”

Line 71: Capitalize Polish

Table 1 seems better placed in the results section rather than the methods section.

Table 1: what is meant in the first row by “man (SD)”? Should this be on a second line?

Line 94: IPAQ has already been abbreviated

Line 104-105: As opposed to what other version? Readers may not be aware that there is a short version.

Line 113: “follow” should be plural

Lines 126: Why were non-parametric tests used?

The figures are very easy to interpret. Nicely done.

Lines 171-172: The authors did notice or did not notice?

Line 193: suggest rewording to indicate government actions “restricting freedom for outdoor physical activities…”

Line 237: I think this is the first time PA has been abbreviated. Please be consistent throughout and abbreviate it as PA from the beginning of the manuscript.

Lines 239-240: I’m confused. Here you state that the participants came from only one university, but on liners 81-82 you state “Students represented a total of 11 Polish universities among 17 different fields of study in technical, medical and humanities disciplines.” Were they from one university of the 11 that were stated in the methods section? This is a major discrepancy.

Line 246: Please change COVIC-19 to “COVID-19”

Lines 246-247: This is an incomplete sentence. Resulted in important what?

Line 247” revise to “a sedentary lifestyle”

Author Response

We thank the reviewer for the constructive comments on our manuscript. We have considered each of your comments and suggestions and we have made appropriate changes. Below are our responses to your remarks on a point-by-point basis.

I would suggest using the abbreviation of PA for physical activity throughout.

Thank your for pointing this out. We have adjusted the manuscript according to your suggestion.

Lines 52-53: Can the authors please expand on why/what specific restrictions imposed barriers on outdoor activities?

We explained the limitations of the lines 52-54.

Table 1 seems better placed in the results section rather than the methods section.

Table 1: what is meant in the first row by “man (SD)”? Should this be on a second line?

We have moved the table to the results section. The "man (SD)" contains an error, which should be "mean (SD)". We apologize for the obvious error.

Concern 2, 4, 5, 6, 7, 8, 12, 15, 19, 21

Thank you for all spelling suggestion. We have included all of them in the manuscript

Lines 126: Why were non-parametric tests used?

A non-parametric test was used, as this was indicated by the analysis of the distribution of variables (Shapiro-Wilk test). We assumed the critical value for 90 participants, obtained from distribution tables W. The W value for 90 participants with p< 0.5 is 0.962. Each value achieved was lower than the critical value, which suggests that the distribution of the analyzed variable is different from normal distribution. The following results were obtained for individual parts of IPAQ: Part 1: 0.518; Part 2: 0.757; Part 3: 0.732; Part 4: 0.886; Total: 0.712; Sitting: 0.930.

Line 104-105: As opposed to what other version? Readers may not be aware that there is a short version.

Thank you for that suggestion, we made complement in line 107.

Line 193: suggest rewording to indicate government actions “restricting freedom for outdoor physical activities…”

Thank you for that suggestion. We've changed the sentence structure.

Lines 239-240: I’m confused. Here you state that the participants came from only one university, but on liners 81-82 you state “Students represented a total of 11 Polish universities among 17 different fields of study in technical, medical and humanities disciplines.” Were they from one university of the 11 that were stated in the methods section? This is a major discrepancy.

We apologize for this error. We are not able to answer where this error came from. As indicated in the participants' section, the study included 11 universities. We have removed the false sentence.

Lines 246-247: This is an incomplete sentence. Resulted in important what

We apologize for the error resulting from the unsuccessful attempt to shorten the conclusions

Reviewer 2 Report

The authors took into account most of my comments in the revised manuscript. However, they did not avoid other errors that must be corrected. Here are my comments:

Introduction: The Authors hypothesized that the introduced restrictions would affect the level of physical activity undertaken in healthy young adult people during lockdown (verses 72-74). This hypothesis is doubly incorrect. Firstly, to be able to investigate whether lockdown has affected on the level of physical activity, you need pre-lockdown data. Secondly, the hypothesis should include an assumption about the direction of the influence. It is not enough to say that it does.
In the introduction, the authors made a short review of the literature and justify the research with one sentence, but I still feel that it was not done enough. But perhaps this is just my subjective impression and stems from my vision of a well-written introduction. Nevertheless, the "introduction" in this form is already acceptable, except for the hypothesis that must be corrected.
By asking questions in the first round of review: What did the authors want to show? Did the authors want to show that the restrictions introduced were effective? What is the new discovery? How did the authors to expect as a specific practical application? - I expected an answer related to the assessed research, not information about the entire project. Therefore, the questions posed remain valid. The answers to these questions should be visible in the introduction and conclusions.
In the Conclusion section, incorrectly formulated conclusions were corrected, but the only practical conclusion comes down to a trivial statement: „In order to avoid negative effects of sedentary lifestyle, it is necessary to promote activity to prevent various diseases” (verses 247-248). Such a practical conclusion can be made without conducting research. In order for the research to have any practical value, detailed recommendations should be formulated.

Author Response

1. Introduction: The Authors hypothesized that the introduced restrictions would affect the level of physical activity undertaken in healthy young adult people during lockdown (verses 72-74). This hypothesis is doubly incorrect. Firstly, to be able to investigate whether lockdown has affected on the level of physical activity, you need pre-lockdown data. Secondly, the hypothesis should include an assumption about the direction of the influence. It is not enough to say that it does.

Thank you for pointing this out. We agree that in the first version of the manuscript we incorporated a wrong perspective on the analyzed data. We reversed the order of analyzed pre-post data because we assumed that the level of physical activity post-lockdown will be equal to the activity before the lockdown, which is obviously a mistake because we did not analyze the activity before and it is based only on our preconceptions. We have improved the manuscript to be based only on the analyzed components.

2. In the introduction, the authors made a short review of the literature and justify the research with one sentence, but I still feel that it was not done enough. But perhaps this is just my subjective impression and stems from my vision of a well-written introduction. Nevertheless, the "introduction" in this form is already acceptable, except for the hypothesis that must be corrected.

Thank you for that suggestion. The sensation of too short a review of the literature may be caused by the deletion of some general information on the impact of physical activity on health (which was changed in 1 review). We also completed the introduction to enter information about eLearning and physical activity.

3. By asking questions in the first round of review: What did the authors want to show? Did the authors want to show that the restrictions introduced were effective? What is the new discovery? How did the authors to expect as a specific practical application? - I expected an answer related to the assessed research, not information about the entire project. Therefore, the questions posed remain valid. The answers to these questions should be visible in the introduction and conclusions.

Being aware of the consequences of the lack of appropriate dose of movement on health, we focused on the future with worries. We have not measured the PA before the lockdown, which would be most methodologically correct, but the pace of development of the epidemic situation in the country simply made it impossible and the situation surprised everyone. We wanted to see the differences in activity levels during the lockdown and after the release of restrictions. Our broad idea is still to generate practical conclusions from the ongoing study and to continue it in order to provide society knowledge and solutions, on how to maintain health through movement, as well as to bring to the attention of the government/the university's management the necessity of introducing systemic solutions related to physical activity during the pandemic. We therefore recommend to follow the scientific guidelines for undertaking physical activity (i.e. WHO) during pandemic or individual consultation with a personal trainer or physiotherapist in order to maintain an appropriate pro-healthy dose of exercise. We also pointed out that the practical effect of this study may be to create PA-related programmes for students during eLearning. Lines: 66-76 and 248-253.

4. In the Conclusion section, incorrectly formulated conclusions were corrected, but the only practical conclusion comes down to a trivial statement: „In order to avoid negative effects of sedentary lifestyle, it is necessary to promote activity to prevent various diseases” (verses 247-248). Such a practical conclusion can be made without conducting research. In order for the research to have any practical value, detailed recommendations should be formulated.

Thank you very much for pointing this out. We agree that this was a weak point in the paper. We corrected the conclusions by providing the practical information.

Round 3

Reviewer 2 Report

In this revised manuscript Authors answered to all my question and took into consideration all my recommendations. In my opinion, the introduction provides now a good, generalized background of the topic. I think the motivations for this study is enough as well. The objective is clearly defined but I still think that the overall value and originality of the paper is average, although I suppose that due to the current topic, the paper could be interesting to a large audience. The conclusion from the research is very general and I would expect detailed recommendations. Thank you very much for allowing me to prepare this review.