A Systematic Review of the Effects of Nutrient Intake in Handball Players on Exercise Performance
, Alejandro Lopez-Moro 1, Luis Javier Chirosa-Rios 2 and Miguel Mariscal-Arcas 1,*Round 1
Reviewer 1 Report
Good work! Just some questions please authors reply:
1. “Está revisión se llevó a cabo siguiendo las recomendaciones y criterios establecidosen las directrices de la declaración” (n 64-65). Sorry, I cannot understand Spanish, please write in English.
2. In the search method, What is the time range for searching articles? No time limit?
3. In the study retrieval process (Figure 1), 85 articles were included to compare results. Could you explain the collection criteria of these articles and how you searched for them?
4. In the study, it can be found that not all the included articles were shown in the tables and discussed. Why were some articles excluded? What are the characteristics of the excluded articles?
Author Response
REVIEW 1
Good work! Just some questions please authors reply:
- “Está revisión se llevó a cabo siguiendo las recomendaciones y criterios establecidosen las directrices de la declaración” (n 64-65). Sorry, I cannot understand Spanish, please write in English.
RESPONSE: The authors are grateful for the reviewer's observation that there was indeed a transcription error. It has been corrected.
- In the search method, What is the time range for searching articles? No time limit?
RESPONSE: The small number of publications on this topic finally led us to use as inclusion criteria those papers published between 1989 and 2022. This data has been included in the section on inclusion and exclusion criteria.
- In the study retrieval process (Figure 1), 85 articles were included to compare results. Could you explain the collection criteria of these articles and how you searched for them?
RESPONSE: The authors are grateful for the reviewer's comment, as there is indeed a transcription error in the figure. The articles included in the study were 44. The articles that were used to compare results in the drafting of the manuscript were included in the bibliography section but were not part of the results of the manuscript. The figure has been corrected.
- In the study, it can be found that not all the included articles were shown in the tables and discussed. Why were some articles excluded? What are the characteristics of the excluded articles?
RESPONSE: The authors are grateful for the reviewer's comment, as there is indeed a transcription error in the figure. The articles included in the study were 44. The articles that were used to compare results in the drafting of the manuscript were included in the bibliography section but were not part of the results of the manuscript. The figure has been corrected.
The changes requested by the Reviewer have allowed the manuscript to be substantially corrected and improved, for which the authors are very grateful.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This type of systematic review is interesting for the researcher, athletes, and sports personnel. Some areas require rewriting or clarification. I am going to comment on these areas point by point.
1. Title is not appropriate as it's a systematic review. "A review of the effects of nutrient intake in elite handball players on exercise performance"
2. The rationale of the study was not properly justified.
3. The registration for the systematic review was not done.
4. Search strategies were not clearly mentioned.
5. Search of each database should be clear.
6. Inclusion and exclusion criteria should be based on the PICO.
7. Risk of bias assessment was not performed.
8. Methodological quality was not checked.
9. Figure 1 is incomplete. It should be based on the CONSORT flow diagram.
10. Each article does not screen properly. Information missing.
11. Does the manual search was performed or not? And why?
I did not review the discussion part because of the above-mentioned issues.
Author Response
REVIEW 2
This type of systematic review is interesting for the researcher, athletes, and sports personnel. Some areas require rewriting or clarification. I am going to comment on these areas point by point.
- Title is not appropriate as it's a systematic review. "A review of the effects of nutrient intake in elite handball players on exercise performance"
RESPONSE: The authors are grateful for the proposal to improve the title, making it more appropriate for the type of work presented. The proposed changes to the title have been made.
- The rationale of the study was not properly justified.
RESPONSE: The authors have tried to expand the introductory section in order to find a clearer and more appropriate justification.
- The registration for the systematic review was not done.
RESPONSE: The authors are grateful for the reviewer's comment. The systematic review was registered in PROSPERO under reference 378107. It has also been included in the text of the manuscript.
- Search strategies were not clearly mentioned.
RESPONSE: The authors have expanded this section by trying to clarify search strategies.
- Search of each database should be clear.
RESPONSE: The authors have expanded this section by trying to clarify search of each database.
- Inclusion and exclusion criteria should be based on the PICO.
RESPONSE: The authors are grateful for the reviewer's comment on the PICO-based criteria. This information has been included as follows: "The PICO system was used for the formulation of questions in the paper (P: Beach and court handball athletes of any level, age, category and gender; I: Dietary habits; C: Sport-specific recommendations and demands of handball and team or intervallic sports with high-intensity actions; O: Improvement of sport performance)".
- Risk of bias assessment was not performed.
RESPONSE: Risk of bias assessment was performed using blinded Cochrane risk of bias tool. This information has been included in the text.
- Methodological quality was not checked.
RESPONSE: The methodological quality was checked using the Cochrane blinded criteria and under the indexed quality of the scientific journals used in the systematic review.
- Figure 1 is incomplete. It should be based on the CONSORT flow diagram.
RESPONSE: Figure 1 has been improved and corrected. We based the diagram on the standard diagram in the final section of the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement.
- Each article does not screen properly. Information missing.
RESPONSE: We have tried to specify more clearly, in the revised manuscript, the process of study selection and classification.
- Does the manual search was performed or not? And why?
RESPONSE: The search was carried out blindly and manually, during the course of the work. Even so, we have tried to specify it in the "material-methods" section.
I did not review the discussion part because of the above-mentioned issues.
RESPONSE: The authors are grateful for the reviewer's comments which have undoubtedly improved the quality of the manuscript. We hope you will be able to review the discussion section and hope that you will enjoy it because of the interest that the authors have shown in the drafting of this section.
Author Response File: Author Response.pdf
Reviewer 3 Report
In general terms, I think that the content of this manuscript is very interesting and has a direct application in the knowledge and development of better nutrition in the field of handball (I even think that it could be transversal to other activities). Through this review, the quality of high-performance sports can be improved. Thus, as Authors exalt in the text, despite the professionalization, there is no clear knowledge of the positive effects of a good diet on the performance of the players.
I have a couple of comments that could improve the quality of the manuscript:
- Be careful with the language, Spanish is used at the beginning of the Materials and Methods section.
- Adding a paragraph at the end of the introduction section briefly indicating the sections could improve and speed up the understanding of the article.
Comments for author File: Comments.pdf
Author Response
REVIEW 3
In general terms, I think that the content of this manuscript is very interesting and has a direct application in the knowledge and development of better nutrition in the field of handball (I even think that it could be transversal to other activities). Through this review, the quality of high-performance sports can be improved. Thus, as Authors exalt in the text, despite the professionalization, there is no clear knowledge of the positive effects of a good diet on the performance of the players.
I have a couple of comments that could improve the quality of the manuscript:
- Be careful with the language, Spanish is used at the beginning of the Materials and Methods section.
RESPONSE: The authors would like to thank the Reviewer for your comments and fully agree on the importance of this type of work for the improvement of players' sporting performance. The English version has been revised, eliminating the Spanish phrase that had been left untranslated due to a transcription error.
- Adding a paragraph at the end of the introduction section briefly indicating the sections could improve and speed up the understanding of the article.
RESPONSE: A great idea that certainly enriches the manuscript. The authors have tried to expand at the end of the introduction in line with the reviewer's comments.
Author Response File: 
Author Response.docx
Round 2
Reviewer 1 Report
Thanks for the authors' reply. No more questions.
Author Response
Thanks for the authors' reply. No more questions.
REPONSE: The authors are grateful for the work done by reviewer 1, which has undoubtedly enriched and improved the submitted manuscript.
Author Response File: Author Response.pdf
Reviewer 2 Report
Add a conclusion in the abstract in line with the study's objective.
As the study's objective mentioned, analyse the nutritional status of beach and court handball athletes, both male and female, of any age range, level and category.
There were no separate findings discussed related to the….
beach and court handball players.
Male and female players
By age range
level of sports participation.
Category of sports participation.
Search strategies for each database should be provided separately.
How does the author determine handball sports' specific and general nutritional intake demands?
Author Response
Add a conclusion in the abstract in line with the study's objective.
RESPONSE: The proposed changes to the abstract have been made.
As the study's objective mentioned, analyse the nutritional status of beach and court handball athletes, both male and female, of any age range, level and category.
There were no separate findings discussed related to the….
beach and court handball players.
Male and female players
By age range
level of sports participation.
Category of sports participation.
Search strategies for each database should be provided separately.
RESPONSE: Many of the articles obtained were located in duplicate in different databases, so we decided not to distinguish the searches and the aspects mentioned according to their location in the corresponding databases.
Nevertheless, these are key considerations in relation to the objective of the review, so we tried to include them separately in the tables of the results and to specify them beforehand in the following citations:
“Of these, only 3 studies included a sample of beach handball athletes (36,47,61). In ad-dition, the great majority of them presented samples of athletes with mean age over 18 years or senior category (19,22-30,32-34,37-44,49-52,54,55,58,60,61). In relation to the sex of the athletes, 13 studies included in their sample only male handball athletes (19,25,26,28,29,35,35,41,51,52,54,55,60,61), 19 did so with female samples (21, 23,24,27,30-34,37,38,40,42,46,49,53,57-59), 9 dealt with mixed samples including both sexes (20,36,39,43-45,48,56,62) and 3 other articles did not specify the sex of the sample used (22,47,50). In relation to the level of the athletes, the results obtained from the different studies showed a wide variability.”
How does the author determine handball sports' specific and general nutritional intake demands?
RESPONSE: Depending on the subject to be assessed and the availability of data on it, different criteria were considered (treated in more depth in the discussion section). For example:
- Hydration: body weight losses and sweating rates in handball athletes during and after the specific sport activity, sodium losses in sweat in handball players....
- Energy: use of formulas, indirect calorimetry, DLW for estimating TEE, spiroergometry for estimating expenditure during activity...
- Macronutrients: recommendations adjusted to the sport modality of high prestige associations in sports nutrition (e.g. ACSM), or specific remarkable techniques performed in a study included in the manuscript as the NBAL.
- Micronutrients: biochemical tests, recommended intakes...
Author Response File: Author Response.pdf
