Prospective Analysis of Levels and Correlates of Physical Activity during COVID-19 Pandemic and Imposed Rules of Social Distancing; Gender Specific Study among Adolescents from Southern Croatia
Round 1
Reviewer 1 Report
It is a pleasure for me to have the opportunity to review a manuscript with a subject as current as the one presented by you.
In general, the article is well structured, developed and finalized. However, there are certain aspects of the manuscript that I would like to highlight.
- First of all, I would not include abbreviations in the abstract and you would start using them in the body of the manuscript.
- Secondly, despite the quality of the introduction, I would extend it with recent studies carried out on the European adolescent population (see AdolesHealth Study)
- Thirdly, and referring to the physical tests used to analyze the level of physical activity of the participants, I would like to know why these tests have been used and not those included in the Alpha Fitness or Eurofit batteries.
- Fourthly, I suggest that the authors reduce the size of the tables, either by elaborating figures or by dividing the tables. It is not easy to read a table when the table header is on a different page.
In relation to the conclusions, I suggest reducing their size and expressing only the most important and significant results of the manuscript.
I consider this to be a good piece of research and I am in favour of its publication but before giving final approval I would like to receive a response to the aspects mentioned above.
Author Response
Reviewer 1
It is a pleasure for me to have the opportunity to review a manuscript with a subject as current as the one presented by you.
In general, the article is well structured, developed and finalized. However, there are certain aspects of the manuscript that I would like to highlight.
RESPONSE: Thank you for your support and for recognizing the importance of our work. Also, thank your comments. We tried to follow it, and amended the manuscript accordingly. Please see below for more details on changes and improvements.
First of all, I would not include abbreviations in the abstract and you would start using them in the body of the manuscript.
RESPONSE: The abbreviations are generally omitted in the abstract of the revised manuscript. We retained only PAL and COVID-19 as abbreviations (please see Abstract)
Secondly, despite the quality of the introduction, I would extend it with recent studies carried out on the European adolescent population (see AdolesHealth Study)
RESPONSE: Thank you for your suggestion. In this version of the manuscript two references related to AdolesHealth study are cited (doi:10.3390/ijerph16224479.; doi:10.3390/nu11092009)
Thirdly, and referring to the physical tests used to analyze the level of physical activity of the participants, I would like to know why these tests have been used and not those included in the Alpha Fitness or Eurofit batteries.
RESPONSE_ Indeed, we missed to properly address the selection of the tests. basically, it is related to the fact that these tests are used in regular scholastic system in Croatia, and are therefore mandatory for all high schools in the country. This is not clearly stated in the Methods, and text reads: “Physical fitness was evidenced by variables included in the mandatory fitness-panel in Croatian educational system. Therefore, in this study we evaluated measuring broad jump (Broad-jump), the maximal number of sit-ups performed in 60 seconds (Sit-ups), static hold in hanging with bent-arms (Bent-arm-hang), a sit-and-reach test (Sit-and-reach), 400 meter run (Run-400m), and a multilevel endurance fitness test (Multilevel-test).” (please see 3rd paragraph of the Variables subsection). Thank you.
Fourthly, I suggest that the authors reduce the size of the tables, either by elaborating figures or by dividing the tables. It is not easy to read a table when the table header is on a different page.
RESPONSE: Thank you for noticing it. In this version of the manuscript the original large tables (Table 2) is now presented in three tables (now Tables 2-4). Also, the corresponding text in Results section is adapted accordingly.
In relation to the conclusions, I suggest reducing their size and expressing only the most important and significant results of the manuscript.
RESPONSE: Indeed, the similar amendments were suggested by other Reviewers. Conclusion is consequently significantly reduced and we tried to be focused on most important issues, only. Bottom line, the Conclsuion section in the original version of the manuscript included 406 words, and in the revised version includes 236 words.
I consider this to be a good piece of research and I am in favour of its publication but before giving final approval I would like to receive a response to the aspects mentioned above.
RESPONSE: Once again, we would like to express our gratitude for your comments and suggestions. Staying at your disposal.
Authors
Reviewer 2 Report
The stated aim of the study looks promising.
(17) “The aim of this study was to evaluate the trends of changes in physical-activity levels (PAL) in adolescents, factors that may be associated to PAL, and changes in PAL among the studied adolescents.”
91) “This prospective study aimed to evaluate changes in PAL among urban adolescents from southern Croatia.”
The theme is an interesting, current and important widely discussed health issue. There is a large research sample, rich literature resources and unique circumstances. However, this paper needs more; it should be more elaborately designed and processed.
It could be a suitable starting point or a component of a larger study, (which is mentioned by the authors).
The key result “decrease in physical activity under pandemic restrictions” seems evident from the very beginning.
(26)“A significant decrease of physical-activity levels was evidenced for total sample.”
(357)”The study evidenced a significant decrease in PAL among adolescents from southern Croatia during the COVID-19 pandemic.”
(40) Claiming that “Physical activity is known to be an important public-health concern” is supported by a source from Lancet – from such a prestigious journal. From such a source, it is desirable to get information that is more expert.
The importance of physical activity is rather superficially described together with diseases, reasons of reduced activity and current trends, however supported by latest studies both global and local.
The intention is great because the presented paper is an actual case study with capacity to be beneficial in the local scene as well as become a part of, e.g., a comparative study on a larger scale.
Errors - Mistakes:
68) a mistake in figures – (confirmed cases)
The current coronavirus disease (COVID-19) is causing global health concerns. With almost 2 confirmed cases, and more than 130.000 deaths (on a day of April 16th 2020), COVID-19 has an impact on majority of world population, and there is practically no region that is not directly or indirectly impacted by this threat [16] (missing full stop)
literary- literacy
(327)The majority of the previously discussed factors that determined the influence of baseline fitness level on follow-up PAL can be conceptualized through the term of physical literary [38]. Specifically, physical literacy can be described as the motivation, confidence, physical competence, knowledge, and understanding to value and take responsibility for engagement in physical activities for life.
Long sentences
e.g.
100 Long sentences – e.g., “Since the study was originally initiated as part of another investigation (“Physical activity, substance misuse, and factors of influence in adolescence”), all participants were previously informed about the study aims, risks, and benefits, and parental consent was obtained before the study baseline (please see later text for study design) The original study was approved by the Ethical Board of the University of Split, Faculty of Kinesiology (EBO: 2181-205-05-02-05-14-005), and changes in the study design related to the research presented here were additionally confirmed by the same Ethical Board (EBO: 2181-205-05- 108 02-05-14-005-A1).
Author Response
Reviewer 2
The stated aim of the study looks promising.
(17) “The aim of this study was to evaluate the trends of changes in physical-activity levels (PAL) in adolescents, factors that may be associated to PAL, and changes in PAL among the studied adolescents.”
91) “This prospective study aimed to evaluate changes in PAL among urban adolescents from southern Croatia.”
RESPONSE: Thank you for recognizing the value of our idea.
The theme is an interesting, current and important widely discussed health issue. There is a large research sample, rich literature resources and unique circumstances. However, this paper needs more; it should be more elaborately designed and processed.
RESPONSE: Thank you for your suggestions. We tried to follow it and amended the manuscript specifically.
It could be a suitable starting point or a component of a larger study, (which is mentioned by the authors).
The key result “decrease in physical activity under pandemic restrictions” seems evident from the very beginning.
RESPONSE: Indeed, the key result was pretty expected. However, and as our results pointed out, the decrease was “unsimilar” across genders. However, we must thank you for your notation. In the revised version of the paper we noted it in the study aim, and text reads: This prospective study aimed to evaluate the level of changes in PAL among adolescents from southern Croatia, specifically for boys and girls.” (please see last paragraph of the Introduction). Also, the aim is amended in the Abstract section, and now reads: “The aim of this study was to evaluate the trends of changes in physical-activity levels (PAL) in adolescents, and factors that may be associated to PAL, and changes in PAL among the studied adolescentsboys and girls.”
(26)“A significant decrease of physical-activity levels was evidenced for total sample.”
RESPONSE: The sentence is amended and reads: “A significant decrease of physical-activity levels was evidenced for total sample (t-test = 3.46, p < 0.001), which was primarily influenceds by significant decrease of physical-activity in boys (t-test = 5.15, p < 0.001).”. Thank you!
(357)”The study evidenced a significant decrease in PAL among adolescents from southern Croatia during the COVID-19 pandemic.”
RESPONSE: The conclusion section you are refereeing is systematically rewritten and is now significantly shorter (previously more than 400 words, and in the revised version about 230 words). We hope that your suggestion is also included in this version of the text.
(40) Claiming that “Physical activity is known to be an important public-health concern” is supported by a source from Lancet – from such a prestigious journal. From such a source, it is desirable to get information that is more expert.
RESPONSE: Thank you for your suggestion. The cited part of the text is now amended and reads: “Physical activity provides numerous benefits, including those directly related to the prevention of cardiovascular diseases, Type II diabetes, colonic cancer, and obesity [1-3]. Therefore, reaching the appropriate physical activity levels is important public-health concern. [1,4].” (please see beginning of the 1st paragraph of the Introduction)
The importance of physical activity is rather superficially described together with diseases, reasons of reduced activity and current trends, however supported by latest studies both global and local.
The intention is great because the presented paper is an actual case study with capacity to be beneficial in the local scene as well as become a part of, e.g., a comparative study on a larger scale.
RESPONSE: Indeed, “providing specific evidences about importance of physical activity” is undoubtedly important. This was one of the main objectives of our study as well. Thank you for recognizing it.
Errors - Mistakes:
68) a mistake in figures – (confirmed cases)
RESPONSE: Thank you for noticing it. Text is corrected and now reads “The current coronavirus disease (COVID-19) is causing global health concerns. With almost 2.5 million confirmed cases, and more than 130.000 deaths (on a day of April 16th 2020), COVID-19 has an impact on majority of world population, and there is practically no region that is not directly or indirectly impacted by this threat [18].” (please see 3rd paragraph of the Introduction).
The current coronavirus disease (COVID-19) is causing global health concerns. With almost 2 confirmed cases, and more than 130.000 deaths (on a day of April 16th 2020), COVID-19 has an impact on majority of world population, and there is practically no region that is not directly or indirectly impacted by this threat [16] (missing full stop)
RESPONSE: Thank you. Corrected.
literary- literacy
(327)The majority of the previously discussed factors that determined the influence of baseline fitness level on follow-up PAL can be conceptualized through the term of physical literary [38]. Specifically, physical literacy can be described as the motivation, confidence, physical competence, knowledge, and understanding to value and take responsibility for engagement in physical activities for life.
RESPONSE: Thank you. Text is amended accordingly and now reads: “The majority of the previously discussed factors that determined the influence of baseline fitness level on follow-up PAL can be conceptualized through the term of physical literacy [40].” (please see last paragraph of the subsection 4.2)
Long sentences
e.g.
100 Long sentences – e.g., “Since the study was originally initiated as part of another investigation (“Physical activity, substance misuse, and factors of influence in adolescence”), all participants were previously informed about the study aims, risks, and benefits, and parental consent was obtained before the study baseline (please see later text for study design) The original study was approved by the Ethical Board of the University of Split, Faculty of Kinesiology (EBO: 2181-205-05-02-05-14-005), and changes in the study design related to the research presented here were additionally confirmed by the same Ethical Board (EBO: 2181-205-05- 108 02-05-14-005-A1).
RESPONSE: Thank you for noticing it. Text is amended and now reads: “Therefore, all participants were previously informed about the study aims, risks, and benefits, and parental consent was obtained before the study baseline (please see later text for study design). The original study was approved by the Ethical Board of the University of Split, Faculty of Kinesiology (EBO: 2181-205-05-02-05-14-005), and changes in the study design related to the research presented here were additionally confirmed.” (please see 1st paragraph of the Materials and Methods section)
Once again, thank you for your support and suggestions
Staying at your disposal
Authors
Reviewer 3 Report
GENERAL COMMENTS
The present study aims to evaluate the physical activity level in a Croatian adolescents cohort during social distancing period due to COVID-19.
Results and information are interesting and, more important, new about this particular period. Physical activity level is lowered compared to the period before the social distancing rules, with differences between genders. However, this decrement could be considered obvious when considering the questionnaire items related predominantly to sports, physical education and active transportations. Interesting correlation are pointed out between baseline and follow-up data.
In my opinion some details need to be better specified and clarified.
TITLE
In my opinion, “Sustainability” is not the correct verb: you just assessed the physical activity level. The use of verb “Sustainability” suggests to the reader that your work concerns how to continue practicing physical activity during the period of social distancing. You assessed the level of physical activity, not if it is actually conducted at home and in what way.
ABSTRACT
- Line 26: you have already introduced the abbreviation for “physical activity level”.
- Lines 33: what do you mean with “specific of physical activity”? You should better clarify this point.
INTRODUCTION
- Line 40: you utilized the abbreviation PA without introducing it.
- Line 42: I also suggest you these works related to the beneficial effects of physical activity on health: doi: 1007/s11332-019-00573-x, doi: 10.1007/s11332-017-0398-x, doi: 10.1111/ecc.12617, doi: 10.1177/1534735416651719.
- Line 68: maybe the number “2” is not correct.
MATERIALS AND METHODS
- Lines 100-101: please specify better the amount of physical education hours and the extracurricular activities. This is an interesting point, whose analysis is also missing in the results section. In lines 140-142, the authors specify that the items focused on practised sports and from the answers it is possible to delineate which kind of physical activity that the participants practiced.
- Please report reference 23 in English.
- Cronbach ά and values referred to reliability of the questionnaire are missing.
- Who supervised the test execution? Was he/she a sport specialist?
- What do you mean with the following sentence: “Since all variables but gender were found to be normally distributed”.
- If not variables were normally distributed, is it correct to use the statistical methods you described?
RESULTS
- In my opinion, the results section should better report the descriptive data, i.e. mean values and SD are missing for physical test. Maybe the differences you see among genders at the follow-up could be also explained by a baseline differences in performance.
- As previously said, it would be very interesting an analysis of the different physical activities and sports. This is a topic largely explained in the discussion section (lines 271-276).
- In each table the p-values should be better specify in order to understand if the correlation are weak or strong.
DISCUSSION
- Lines 292-296: in my opinion, the authors may be less assertive in their conclusions regarding this part (i.e. clearly points, line 293). The results support their opinion, but there could be other reasons explaining the outcomes. Furthermore, it should take into account that data derive from a questionnaire, which is a subjective tool and we do not really know if the participants answer in a sincere way.
- Lines 303-325: please specify that you do not have collected this kind of data and that they are only supposition. Focusing on the parents role, you do not know if the adolescents are at home with their parents or not. Moreover, you have no data about the parents influence on the physical activity level of the participants.
CONCLUSIONS
In my opinion, this section should be more concise and brief, explaining the more relevant results with a short description of the possible explanation.
Author Response
Reviewer 3
GENERAL COMMENTS
The present study aims to evaluate the physical activity level in a Croatian adolescents cohort during social distancing period due to COVID-19.
Results and information are interesting and, more important, new about this particular period. Physical activity level is lowered compared to the period before the social distancing rules, with differences between genders. However, this decrement could be considered obvious when considering the questionnaire items related predominantly to sports, physical education and active transportations. Interesting correlation are pointed out between baseline and follow-up data.
In my opinion some details need to be better specified and clarified.
RESPONSE: Thank you for recognizing the potential in our work. Also, thank you for your elaborated and constructive comments and suggestions. We tried to follow it, and amended the manuscript accordingly. In the following text we specified the amendments and indicated where to find the changes in the revised version of the manuscript. Staying at your disposal.
TITLE
In my opinion, “Sustainability” is not the correct verb: you just assessed the physical activity level. The use of verb “Sustainability” suggests to the reader that your work concerns how to continue practicing physical activity during the period of social distancing. You assessed the level of physical activity, not if it is actually conducted at home and in what way.
RESPONSE: Thank you for your observation. The title is changed accordingly and now reads: Prospective analysis of levels and correlates of physical-activity during COVID-19 pandemic and imposed rules of social distancing; gender specific study among adolescents from southern Croatia
ABSTRACT
Line 26: you have already introduced the abbreviation for “physical activity level”.
RESPONSE: Thank you. Corrected.
Lines 33: what do you mean with “specific of physical activity”? You should better clarify this point.
RESPONSE: Indeed, the statement was not clear. Text is amended and now reads: “Differences in PAL changes between genders were probably related to the fact that PAL among boys was mostly related to participation in organized sports.
INTRODUCTION
Line 40: you utilized the abbreviation PA without introducing it.
RESPONSE: Thank you. Text is amended and now reads: “Physical activity provides numerous benefits, including those directly related to the prevention of cardiovascular diseases, Type II diabetes, colonic cancer, and obesity [1-3]. Therefore, reaching the appropriate physical activity levels is important public-health concern. [1,4].“ (please see first two sentences of the Introduction).
Line 42: I also suggest you these works related to the beneficial effects of physical activity on health: doi: 1007/s11332-019-00573-x, doi: 10.1007/s11332-017-0398-x, doi: 10.1111/ecc.12617, doi: 10.1177/1534735416651719.
RESPONSE: Thank you for your suggestion. Two of specified references are included in the revised version of the text.
Line 68: maybe the number “2” is not correct.
RESPONSE: Thank you for noticing it. It is corrected (2.5 millions)
MATERIALS AND METHODS
Lines 100-101: please specify better the amount of physical education hours and the extracurricular activities. This is an interesting point, whose analysis is also missing in the results section. In lines 140-142, the authors specify that the items focused on practised sports and from the answers it is possible to delineate which kind of physical activity that the participants practiced.
RESPONSE: Thank you for this suggestion. In this version of the manuscript more details are provided with regard to specific involvement in sport and physical education. Text reads: “All participants were healthy, meaning that they regularly participated in physical education classes 2-times a week, while some of them were involved in extracurricular sporting activities. Specifically, 35% of studied participants reported involvement in organized sport activities at the study baseline (i.e. when fitness variables were collected at the beginning the school years; please see later for study design), and majority of those 35% reported involvement in competitive sports (i.e. football/soccer, handball, martial arts).“ (please see 1st paragraph of the Participants subsection).
Please report reference 23 in English.
RESPONSE: The title of the manuscript is provided in English and reference now reads: Samaržija, D.V.; Mišigoj-Duraković, M. Pouzdanost hrvatske verzije upitnika za procjenu ukupne razine tjelesne aktivnosti djece mlaðe školske dobi. [Reliability of croatian version of the questionnaire for assessment of overall level of physical activity of younger school children] Hrvatski športskomedicinski vjesnik 2013, 28, 24-32.
Cronbach ά and values referred to reliability of the questionnaire are missing.
RESPONSE: In this version of the manuscript, details on reliability of the tests is presented, and text reads: “The PAQ-A was already confirmed as being a valid test for the evaluation of PAL in similar samples of participants from Croatia and the surrounding countries, with reliability indicated by Cronbach Alpha of 0.763 [13,24,25].” (please see 2nd paragraph of the Variables subsection). Thank you.
Who supervised the test execution? Was he/she a sport specialist?
RESPONSE: Yes, all tests were evaluated by experienced evaluator. It is now specified in the text and reads: “All tests were measured by experienced evaluators – physical education teacher.”
What do you mean with the following sentence: “Since all variables but gender were found to be normally distributed”.
If not variables were normally distributed, is it correct to use the statistical methods you described?
RESPONSE: We must agree that the sentence explaining the “normality” was not clear. We intended to specify that “only “gender” was not normally distributed”. We hope it is now more clear. Text reads: “The parametric nature of the variables was checked with the Kolmogorov–Smirnov test for distribution normality, and all variables were confirmed to be normally distributed. Therefore, means and standard deviations were reported for all variables but gender.“ (Please see 1st paragraph of the Statistics)
RESULTS
In my opinion, the results section should better report the descriptive data, i.e. mean values and SD are missing for physical test. Maybe the differences you see among genders at the follow-up could be also explained by a baseline differences in performance.
As previously said, it would be very interesting an analysis of the different physical activities and sports. This is a topic largely explained in the discussion section (lines 271-276).
RESPONSE: In this version of the manuscript we included descriptive statistics for the anthropometric variables and fitness tests, as well as differences between boys and girls. However, since this was nor the primary aim of the study the results of those analysis are provided in the Supplementary table, and briefly presented in the Results section.
With regard to analysis of the specific data related to sport, physical education, active transportation, we must state that this analysis is very limited. Namely, only school based activity (PE and school recess) is evaluated “separately”, but even these results cannot be defined as a percentage of overall PAL-score because total score is calculated as an average value of all items included in the questionnaire. Therefore, for the purpose of this stud we were able to present only “average” result for physical education classes, and this was done in results section.
In each table the p-values should be better specify in order to understand if the correlation are weak or strong.
RESPONSE: Thank you for the suggestion. In the revised version of the manuscript the p-levels are presented as <0.001, <0.01, and <0.05. (please see tables 2-5 and “asterisks”, and legends).
DISCUSSION
Lines 292-296: in my opinion, the authors may be less assertive in their conclusions regarding this part (i.e. clearly points, line 293). The results support their opinion, but there could be other reasons explaining the outcomes. Furthermore, it should take into account that data derive from a questionnaire, which is a subjective tool and we do not really know if the participants answer in a sincere way.
RESPONSE: Thank you for noticing it. Indeed, our statements were somewhat “assertive” and following your suggestions “concluding terms” are replaced with more flexible ones. Text now reads (please pay attention on underlined words): “The fact that baseline fitness status determined the PAL-FU both in boys and girls is one of the most important findings of this study. It probably points to the fact that boys and girls of better (initial) fitness status tended to have higher PAL, even in the period of when situations and imposed rules probably prevented them from being physically active in their usual manner (e.g., participation in organized sports, and physical-education classes)” (please see 1st paragraph of the 4.2 subsection)
Lines 303-325: please specify that you do not have collected this kind of data and that they are only supposition. Focusing on the parents role, you do not know if the adolescents are at home with their parents or not. Moreover, you have no data about the parents influence on the physical activity level of the participants.
RESPONSE: Text is amended as you suggested and now reads: “Although we didn’t collect the data explicitly in this study, it is generally known and therefore expected even herein that adolescents who had better fitness status at the study baseline actually have most of previously specified characteristics (i.e. better self-efficacy, higher intention to exercise) simply because better fitness status, etc.“
Also, the statements about „parental influence“ are also „relaxed“ (i.e. „we may hypothesize“, „could be expected”) For more details please see 3rd paragraph of the subsection 4.2 Thank you.
CONCLUSIONS
In my opinion, this section should be more concise and brief, explaining the more relevant results with a short description of the possible explanation.
RESPONSE: We must agree that the Conclusion was too long. It is highlighted by other Reviewers as well. In the revised version of the paper, the Conclusion is significantly reduced (from more than 400 words to approximately 230 words in the revised version of the paper). We believe that it is now more concise and clear (please see Conclusion section). Thank you.
Staying at your disposal
Authors
Reviewer 4 Report
The authors aim to evaluate the trends of changes in PAL in adolescents from Southern Croatia at two different moments (before and during CoVId-19 confinement).
The idea is quite interesting and the article is easy to read, but several changes should be undertaken to improve its quality in order to be published.
The use of abreviations like PAL, PAL-BL and PAL-FU, and PA is not consistent through the manuscript. Plesase correct this.
An important flaw of the study is the self-reported PAL of adolescents. The effect of the social desireability in answering is always quite high in such studies. Of course due the pandemic the measures of PAL are quite difficult. Did you think about accelerometers ? I guess in Croatia there was no total lockdown as in other countries.
Abstract:
L 17 - 19: Please make sentence easier. You are using PAL three times in a single small sentence.
L20: Use Mage better and skip "of age"
L21 - 22: Redundant use of social distancing
L27: It should say "influenced"
Introduction:
L42: Consider using "physical inactivity" instead of PA here
L42 - 46: Rephrase sentence please. using double parenthesis ...
L46 - 47: Rephrase sentence please
L68: "2" ???? confirmed cases???, skip (on a day of...) better "as of April, ..."etc.
L91 and Participants Section:
Please provide more information about environmental factors which could have influenced PALs (i.e. living in a more rural or urban setting, which makers things quite different), details on adolescents' possibilities to move in their setting or not.
L 109: The current study
L119: As of March 20th
L127: Please use also PAL-BL and PAL-FU
You are referring to "banning of sports-related gatherings, what about individual sports without any contact???)
L 178 ...: Referring to multistage 20 m shuttle run test (Leger et al., 1988)? Léger, L.A.; Mercier, D.; Gadoury, C.; Lambert, J. The multistage 20 metre shuttle run test for aerobic fitness. J. Sports Sci. 1988, 6, 93–101.
As many studies confirm lower PAL among girls in comparison to boys, I think some of the results are quite obvious and foreseeable.
Use also your abreviations in your table 3.
L260 - 263: Redundant use of Covid, pandemic and social distancing ...
Author contributions ??? No information is given so far ...
I would like to encourage the authors to improve the paper as the topic is interesting and concerned and still concerns a huge part of population.
Author Response
Reviewer 4
The authors aim to evaluate the trends of changes in PAL in adolescents from Southern Croatia at two different moments (before and during CoVId-19 confinement).
The idea is quite interesting and the article is easy to read, but several changes should be undertaken to improve its quality in order to be published.
RESPONSE: Thank you for your support. Also, thank you for your comments and suggestions. We tried to follow it and amended the manuscript accordingly. Please see below for responses. Staying at your disposal.
The use of abreviations like PAL, PAL-BL and PAL-FU, and PA is not consistent through the manuscript. Plesase correct this.
RESPONSE: Indeed, there were some inconsistencies in usage of the abbreviations. We believe that it is corrected now.
An important flaw of the study is the self-reported PAL of adolescents. The effect of the social desireability in answering is always quite high in such studies. Of course due the pandemic the measures of PAL are quite difficult. Did you think about accelerometers ? I guess in Croatia there was no total lockdown as in other countries.
RESPONSE: Yes, accelerometers would be better solution, but as stated in the Methods, the study was initiated “independently” of COVID-19, and therefore we were not in situation to adapt the protocol and measurement to situation related to pandemic. However, your comment is now included in the Study limitations. Thank you for understanding.
Abstract:
L 17 - 19: Please make sentence easier. You are using PAL three times in a single small sentence.
RESPONSE: The sentence is amended and now reads: The aim of this study was to evaluate the trends of changes in physical-activity levels (PAL) in adolescents, and factors that may be associated to PAL among the studied boys and girls.”
L20: Use Mage better and skip "of age"
RESPONSE: Amended accordingly, and it now reads: “126 females; mean age: 16.4±1.9 years“
L21 - 22: Redundant use of social distancing
RESPONSE: Thank you; amended accordingly.
L27: It should say "influenced"
RESPONSE: Corrected, thank you.
Introduction:
L42: Consider using "physical inactivity" instead of PA here
RESPONSE: This part of the text is systematicall rewritten (according to suggestion of 1st Reviewer) and now reads: “Physical activity provides numerous benefits, including those directly related to the prevention of cardiovascular diseases, Type II diabetes, colonic cancer, and obesity [1-3]. Therefore, reaching the appropriate physical activity levels is important public-health concern, while some forms of physical activity are proven to be beneficial for persons with severe health conditions [1,4-6].“ (please see first part of the Introduction). Thank you.
L42 - 46: Rephrase sentence please. using double parenthesis ...
RESPONSE: Text is corrected and now reads: “Knowing the problems related to the lack of regular physical work (due to technological advancements), and reduced active transportation (mostly because of a busy every-day schedule and distances that cannot practically be covered by active transportation), reaching an appropriate level of physical activity is an important global topic [7-9].“
L46 - 47: Rephrase sentence please
RESPONSE: Indeded, the sentence was to long and complicated. It is now divided in two, and reads: “The negative influence of reduced physical activity is generally expected in late adulthood. However, knowing that practically all human behaviors related to health are developed and formed in childhood and adolescence, these periods of life are of the upmost importance for the promotion of physical activity [10,11].“
L68: "2" ???? confirmed cases???, skip (on a day of...) better "as of April, ..."etc.
RESPONSE: Yes, it was typewriting mistake (should be 2.5 millions). Sentence now reads: “The current coronavirus disease (COVID-19) is causing global health concerns. With almost2.5 million confirmed cases, and more than 130.000 deaths (as of April 16th 2020), COVID-19 has an, etc.“
L91 and Participants Section:
Please provide more information about environmental factors which could have influenced PALs (i.e. living in a more rural or urban setting, which makers things quite different), details on adolescents' possibilities to move in their setting or not.
RESPONSE: In this version of the manuscript we provided more details about environmental factors. However, we weren’t able to provide more details, because the original study which was approved by Ethical Board didn’t include all details which will be potentially interesting for this manuscript. Hope that you will understand. Text reads: “Participants in this prospective study were adolescents from a Croatian coastal region, specifically, from the Split Dalmatia County. During the course of the study, all participants were attending high school in this region, and majority of them were residentially located in urban regions. At the study baseline, they were 16.4 ± 1.9 years of age (from 15 to 18 years). All participants were healthy, meaning that they regularly participated in physical education classes 2-times a week, while some of them were involved in extracurricular sporting activities. Specifically, 35% of studied participants reported involvement in organized sport activities at the study baseline (i.e. when fitness variables were collected at the beginning the school years; please see later for study design), and majority of those 35% reported involvement in competitive sports (i.e. football/soccer, handball, martial arts).“ (please see begining of the Paricipants subsection)
L 109: The current study
RESPONSE: Amended accordingly. Text now reads: “The current study included two measurements, baseline (done before imposed measures of social-distancing), and follow-up, etc.“
L119: As of March 20th
RESPONSE: Amended and now reads: “Schools and universities were closed in March 2020, while as of 20 March, the government of Croatia implemented other, etc.“
L127: Please use also PAL-BL and PAL-FU
RESPONSE: As you suggested, we included abbreviations in the Figure 1
You are referring to "banning of sports-related gatherings, what about individual sports without any contact???)
RESPONSE: Actually, all “formal” sport gatherings were banned, including individual sports if training was performed in “official” facilities. However, people could do individual training on open areas (parks, forests). It is now more clearly indicated, and text reads: “Meanwhile, there was no strict prohibition of different forms of individual training (i.e. running, cycling).” Thank you.
L 178 ...: Referring to multistage 20 m shuttle run test (Leger et al., 1988)? Léger, L.A.; Mercier, D.; Gadoury, C.; Lambert, J. The multistage 20 metre shuttle run test for aerobic fitness. J. Sports Sci. 1988, 6, 93–101.
RESPONSE: Yes, this was the test we used. The reference is included. Please see last paragraph of the subsection Variables. Thank you.
As many studies confirm lower PAL among girls in comparison to boys, I think some of the results are quite obvious and foreseeable.
RESPONSE: Yes, indeed, results are foreseeable. The reason we specified it is because the situation with baseline PAL in girls was actually “so bad” that even COVID-19 pandemic didn’t significantly reduce their PAL. Hope we will have a chance to present it even in public if paper will hopefully be published.
Use also your abreviations in your table 3.
RESPONSE: Thank you. It is used (note that Table 3 is now table 5)
L260 - 263: Redundant use of Covid, pandemic and social distancing ...
RESPONSE: Amended accordingly. Sentence reads: “There is global concern about PAL reduction as a result of the COVID-19 pandemic [22,23].“
Author contributions ??? No information is given so far ...
RESPONSE: Indeed, we didn’t specify it originally, but it is stated in the revised version. Thank you.
I would like to encourage the authors to improve the paper as the topic is interesting and concerned and still concerns a huge part of population.
RESPONSE: Thank you once again. Hope that you’ll recognize our efforts.
Staying at your disposal.
Round 2
Reviewer 2 Report
Thank you for modifications you have made.
As for the design of your research, it is acceptable.
But could you run the proofreading process once again? E.g., The chapter 4 - Discussion remained the same as it was in the first version, it deserves proofreading.
4. Discussion
Although the results of the study allow a broad discussion on a problem, we next focus on the most important findings related to the study aims. First, a significant decrease of PAL was evidenced for boys. As a result, our initial study hypotheses may be partially accepted. Second, analyses evidenced positive correlation between fitness status and physical-activity levels before and after the imposed rules of social distancing.
402 - This is probably influence y the fact that the PAL.
