Anthropometric Values in Spanish Elite Soccer: Differences between Divisions and Playing Positions

Round 1

Reviewer 1 Report

Thanks for the work. You can find the necessary corrections in the attached file. 

 

Yours sincerely

 

Comments for author File: Comments.pdf

Thanks for the work. You can find the necessary corrections in the attached file. 

Yours sincerely

 

Author Response

The research presented in this article is scientifically conceptualised and executed. However, some areas require attention to reach the level of publication. The authors have made the following revisions:

Response of the authors: We appreciate the reviewer's comments and that he was interested in the work done.

 

Your introduction provides a comprehensive overview of the physical demands of soccer and the factors that influence players' body composition. However, some points can be addressed for improvement. The introduction is detailed; however, some sentences are lengthy and may benefit from breaking them down to improve the readability. Therefore, ensuring that each sentence conveys a clear message is crucial.

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified to facilitate the reading of the study.

 

Ensure that appropriate citations support all claims and statements. For example, when mentioning the average total distance covered by soccer players, refer to [1–6]. It would be helpful to provide specific sources for these claims to enhance the credibility of the article.

Response of the authors: Following the reviewer's suggestions, we have modified the bibliographic references, making reference to studies focused on the physiology of soccer that focus on these parameters and added the UEFA expert consensus, as it is one of the studies with greater impact and enriching in relation to the physiology of soccer.

 

The transition from a general background to a research gap was abrupt. Consider adding a sentence or two to explicitly state the current gap in the literature that this study aims to address.

Response of the authors: Thank you for the comment. We tried to facilitate the reading of the text

 

When discussing factors influencing body composition, you have mentioned the playing position, ethnicity, food habits, individual physiology, playing style, and training volume. It may be beneficial to briefly explain why these factors are particularly relevant for studying the body composition of soccer players.

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified justifying the factors that could affect body composition.

 

When discussing the studies by Sebastiá-Rico et al. [12,13], you mention the differences between measurement methods. These methods are briefly explained and how they relate to body composition assessment in soccer players.

Response of the authors: In accordance with the reviewer's suggestion, a paragraph has been added to briefly explain the mechanism of action of bioimpedance and dual X-ray densitometry.

 

The section on somatotype is informative, but you might want to briefly justify why the somatotype is a relevant tool for your study, specifically on Spanish elite soccer players.

Response of the authors: We appreciate the reviewer's comments. We have included a phrase that justifies its use in soccer teams

 

Overall, your introduction is thorough; however, a few adjustments in terms of clarity, justification, and transitions could enhance its effectiveness.

Response of the authors: Thank you for the comment, we believe that the changes added to the previous comments have improved their understanding.

 

Your Methods section is detailed and well-structured, but a few points could be considered for improvement. Provide more details on the demographic characteristics of the participants, such as the distribution by age within each division. This finding adds to our results.

Response of the authors: We appreciate the reviewer's comments. The age is already included in section 2.2 participants, dividing the total average age and the average age differentiated by divisions.

 

In the exclusion criteria, it would be beneficial to explain why measurements by anthropometrists not accredited by the ISAK were excluded. This added transparency to the methodology.

Response of the authors: Thank you for the comment, we have added a sentence justifying why we decided to exclude those measurements that were not performed using the ISAK method in order to unify the same protocol for all measurements and increase the reliability of the measurement.

 

Expand procedures during training sessions. For instance, how were players selected for measurements on evaluation days? Were any specific instructions given to the players regarding their physical activity before the evaluation?

Response of the authors: We appreciate the reviewer's comments. In section 2.3 procedure the information has been expanded to explain the conditions under which the measurements were performed

 

While you have mentioned the technical error of measurement (TEM), you briefly discussed the significance of these precision levels in the context of your study. This can help readers understand the reliability of data.

Response of the authors: Thank you for the comment, we have added a sentence in 2.4. Anthropometric Measurements justifying the significance of these precision levels.

 

Your Methods section is comprehensive, but addressing these points will enhance the clarity and transparency.

Response of the authors: Thank you for the comment, we believe that the changes added to the previous comments have improved their understanding.

 

Your discussion is comprehensive and summarises the key findings of the study. There are a few suggestions for improvement in this regard. Emphasise the novelty of this study as the first to evaluate and compare body composition among different Spanish soccer divisions and playing positions through anthropometry. We have clearly stated the contribution of our study to the existing literature in this context.

Response of the authors: We appreciate the reviewer's comments and that he was interested in the work done.

 

While you briefly mention the impact of body composition on player performance, consider expanding this aspect. Discuss how the observed differences in body composition among divisions and playing positions may influence players' agility, speed, endurance, and overall performance in the field.

Response of the authors: In accordance with the reviewer's suggestion, we have added more information justifying the importance of body composition in a soccer player's performance.

 

Your discussion emphasises that FM and skinfold sum values may decrease over time in soccer players. Provide a more in-depth discussion of this trend, considering the potential reasons for these changes, such as evolving training methods, dietary practices, or changes in the pace of the game over the years.

Response of the authors: In accordance with the reviewer's suggestion, we have added more information that justifies the tendency of FM to decrease.

 

When comparing our results with previous studies, we discuss potential reasons for discrepancies, such as different methodologies, populations studied, or changes in soccer player characteristics over time. This adds depth to the interpretation of the findings.

Response of the authors: We appreciate the reviewer's comments and that he was interested in the work done.

 

When discussing percentiles, clarify how they can be practically applied by coaching and medical staff. Provide scenarios where percentiles are particularly useful for optimising training and monitoring body composition.

Response of the authors: In accordance with the reviewer's suggestion, we have added more information that justifies the use of percentiles.

 

Your discussion is thorough, but providing a more in-depth analysis and addressing these points could enhance its richness and impact–a well-performed, comprehensive study.

Response of the authors: Thank you for the comment, we believe that the changes added to the previous comments have improved their understanding.

Author Response File: Author Response.pdf

Reviewer 2 Report

 

General Comments:  This is an extensive study with a large amount of data.  My compliments to the authors for undertaking such a project.  However, some of the writing within the text is confusing and a bit difficult to interpret.  It might be good to have someone proficient in English review it for clarification. 

 

Page              Line                                                    Comment

 

1                      6                      “…players between ….: should be “players among” since it is more than 2 divisions.

1                      12                   “an-thropometric” should be “anthropometric”

1                      15                   “body composition between the different levels of Spanish soccer competition.”

2                      12                   “….or musculoskeletal index to provide useful data ….”

2                      24                   What are “challenging-to-control factors”?  Is that the same as
controlling factors”?

2                      41                   Does “different categories”  mean different levels of play?  Since you measured only men, do you need to mention “sexes”?

2                      48                   Does this mean “At lower competition levels, the more differences there will be between playing positions”?

3                      8                      “…. Soccer teams that had a dietitian-nutritionist…”

3                      16                   “Participants came from …..”

3                      18                   Provide a space between “division (mean age: 25.09±5.14 years)….”

3                      40                   “The anthropometric method used to measure body weight was a SECA….”

3                      41                   Use a separate sentence to explain the SECA 217. 

4                      7                      “…the equations described in the consensus document….”

4                      10                   Your should probably provide reference numbers ofr each of the equations mentioned.

4                      13                   “….3, 6, and 8 skinfolds were used to estimate adipose tissue through Kerr’s equation (??)..  In addition, two indices were calculated: ….”

4                      22                   “….which allowed application of parametric tests ….”

4                      30                   “Descriptive statistics (mean±SD) for all kinanthropometric and derived variables were given for according to their division of play……”

4                      33-42             Since much of this is covered in the tables, do you need to include it here?

4                      43-49             This paragraph seems a bit confusing.   Did you covary out position and run comparisons across divisions for these variables?

7                      2                      “….derived variables depending on division…..”

7                      20                   “….showed higher values in MM in kg …..”

10                   14                   “Midfielders showed lower values compared to goalkeepers for …..”

15                   5                      “…greater speed during competition.  In addition, higher FM values have been shown to be…..”

15                   9                      Recently, Ayotte et al. [37] examined….”

15                   21                   These references should be cited by numbers. 

15                   25                   The Carter and Faulkner reference should be cited by number.

15                   26                   “…..lower.  However, it should be noted …”

15                   31                   “…where it was verified that body composition in male professional soccer players from all leagues in the world should by differentiated by the three main ….”

15                   34                   It is not clear what the “first article mentioned” means.  It should be referenced.

15                   35                   “However, in that study, the FM was ….”

16                   11                   Nether the Faulkner  nor Wilmore equations appear to be cited in your references. 

While the paper is fairly well written, it might need to be reviewed by someone with an English speaking background to clarify wording issues.

Author Response

General Comments:  This is an extensive study with a large amount of data.  My compliments to the authors for undertaking such a project.  However, some of the writing within the text is confusing and a bit difficult to interpret.  It might be good to have someone proficient in English review it for clarification.

Response of the authors: Thank you for the comment, we believe that the changes added to the next comments have improved their understanding.

 

“…players between ….: should be “players among” since it is more than 2 divisions.

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

“an-thropometric” should be “anthropometric”

Response of the authors: In accordance with the reviewer's suggestion, the word has been modified.

 

  “body composition between the different levels of Spanish soccer competition.”

Response of the authors: In accordance with the reviewer's suggestion, the word has been modified.

 

“….or musculoskeletal index to provide useful data ….”

Response of the authors: In accordance with the reviewer's suggestion, the word has been modified.

 

What are “challenging-to-control factors”?  Is that the same as controlling factors”?

Response of the authors: Thank you for the comment, yes it’s the same as controlling factors. The sentence has been modified to clarify the meaning.

 

Does “different categories”  mean different levels of play?  Since you measured only men, do you need to mention “sexes”?

Response of the authors: In accordance with the reviewer's suggestion, the word has been modified. We mention sex since it is also necessary to carry out this same study in women's soccer. However, as we have not been able to do so since we did not obtain sufficient data, we have omitted the sex information as you mentioned.

 

Does this mean “At lower competition levels, the more differences there will be between playing positions”?

Response of the authors: Thank you for the comment. Yes, that's what we meant to say. The sentence has been modified.

 

“…. Soccer teams that had a dietitian-nutritionist…”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

“Participants came from …..”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

Provide a space between “division (mean age: 25.09±5.14 years)….”

Response of the authors: In accordance with the reviewer's suggestion, a space has been added.

 

“The anthropometric method used to measure body weight was a SECA….”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

Use a separate sentence to explain the SECA 217.

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

“…the equations described in the consensus document….”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

Your should probably provide reference numbers ofr each of the equations mentioned.

Response of the authors: In accordance with the reviewer's suggestion, the references has been added.

 

“….3, 6, and 8 skinfolds were used to estimate adipose tissue through Kerr’s equation (??)..  In addition, two indices were calculated: ….”

Response of the authors: Thank you for the comment. The sentence was modified. The sum of skinfolds involves measuring the thickness of skin folds in different areas of the body, such as the triceps, abdomen, thigh, among others, and then adding these values to obtain an estimate of the total amount of subcutaneous fat. The adipose tissue was estimated only with Kerr´s equation.

 

“….which allowed application of parametric tests ….”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

“Descriptive statistics (mean±SD) for all kinanthropometric and derived variables were given for according to their division of play……”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

Since much of this is covered in the tables, do you need to include it here?

Response of the authors: Thank you for the comment. We decided to describe these parameters because they were the ones highlighted by the statistical program.

 

This paragraph seems a bit confusing.   Did you covary out position and run comparisons across divisions for these variables?

Response of the authors: Thank you for the comment. Due to the amount of data we obtained, we thought it would be useful to do this in order to detect more differences and be able to comment on them in the article.

 

“….derived variables depending on division…..”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

“….showed higher values in MM in kg …..”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

“Midfielders showed lower values compared to goalkeepers for …..”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

“…greater speed during competition.  In addition, higher FM values have been shown to be…..”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

“Recently, Ayotte et al. [37] examined….”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

These references should be cited by numbers.

Response of the authors: In accordance with the reviewer's suggestion, the references has been added.

 

The Carter and Faulkner reference should be cited by number.

Response of the authors: In accordance with the reviewer's suggestion, the references has been added.

 

“…..lower.  However, it should be noted …”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

“…where it was verified that body composition in male professional soccer players from all leagues in the world should by differentiated by the three main ….”

Response of the authors: In accordance with the reviewer's suggestion, the sentence has been modified.

 

It is not clear what the “first article mentioned” means.  It should be referenced.

Response of the authors: Thank you for the comment. The reference has been added.

 

“However, in that study, the FM was ….”

Response of the authors: Thank you for the comment. The sentence has been modified.

 

Nether the Faulkner nor Wilmore equations appear to be cited in your references.

Response of the authors: Equation references were added earlier after your comments, thanks for the comment.

 

While the paper is fairly well written, it might need to be reviewed by someone with an English speaking background to clarify wording issues.

Response of the authors: Thank you for the comment. We regret the number of spelling mistakes due to the translation from Spanish to English, we hope we have corrected all the annotations correctly.

Author Response File: Author Response.pdf