Effects of the FIFA 11+ and a modified warm-up programme on injury prevention and performance improvement among youth male football players

Mojtaba Asgari; Mohammad Hossein Alizadeh; Shahnaz Shahrbanian; Kevin Nolte; Thomas Jaitner

doi:10.1371/journal.pone.0275545

Peer Review History

Original SubmissionMay 24, 2022
6 Jul 2022 Decision Letter - Rafael Franco Soares Oliveira, Editor PONE-D-22-14375Effects of the FIFA 11+ and a modified warm-up programme on injury prevention and performance improvement among youth male football players.PLOS ONE Dear Dr. Asgari, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. ============================== Please submit your revised manuscript by August 20th of 2022. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. 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" ext-link-type="uri" xlink:type="simple">https://doi.org/10.1007/s40279-015-0404-x" Viewing this article at the Springer website, we see that all content and materials are copyrighted and are not available for re-use without permission. To seek permission from the Springer to publish this Abstract under the Creative Commons Attribution (CC BY) 4.0 License, please contact them with the following text and PLOS ONE Request for Permission form (http://journals.plos.org/plosone/s/file?id=7c09/content-permission-form.pdf): “I request permission for the open-access journal PLOS ONE to publish XXX under the Creative Commons Attribution License (CCAL) CC BY 4.0 (http://creativecommons.org/licenses/by/4.0/). Please be aware that this license allows unrestricted use and distribution, even commercially, by third parties. Please reply and provide explicit written permission to publish XXX under a CC BY license.” Please upload the granted permission to the manuscript as a Supporting Information file. Please note that RightsLink permission forms often impose use restrictions that are incompatible with our CC BY 4.0 license, and we are therefore unable to accept these permissions. For this reason, we ask that you contact the copyright holders with the PLOS ONE Request for Permission form. If you are unable to obtain permission from the original copyright holder, please either remove the Abstract or supply a replacement Abstract that complies with the CC BY 4.0 license. Additional Editor Comments: Dear authors, The work is interesting but some improvements can be made before further consideration. There are some sentence that lack support (references). Some limitations should be added/highlighted as well as some pratical applications for coaches. Thank you [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Yes Reviewer #2: Partly ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: I Don't Know ****** 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: No ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: Yes ****** 5. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: Dear authors, I believe they did a good job and deserve credit for that. The study is well designed, the introduction is robust, the methods are well explained and the discussion supports the results. However, the conclusion can and should be improved, and should be presented with practical applications for the coach. Furthermore, I believe that the limitations should be inserted at the end of the discussion. Reviewer #2: The proposed manuscript is very interesting and has an noteworthy objective. Congratulations to the authors. My suggestions follow below. P.8 Comment 1: Please rephase the “Background”, specifically “…the latter has potentially reduced compliance and implementation of the programme” Comment 2: Keywords: I suggest not repeating the keyword that already exists in the title to enhance search results. Comment 3: “static stretches” in the warm-up? Or did the authors mean “dynamic stretches”? Comment 4: Is the discussion the conclusion in the abstract? P.9 Comment 4: I suggest rephrasing the sentence “It aims to tackle modifiable injury risk factors such as neuromuscular control, static and dynamic balance, and the hamstring/quadriceps strength ratio[8].” as they are not risk factors. They can be considred as “key elements of effective injury prevention programmes…” Comment 5: Please rephrase the sentence “The latter, along with barriers such as prolonged duration, concerns regarding some exercises, and lack of a link to football-specific targets[14, 18], has been discussed as a potential reason for low compliance and poor implementation of the programme[14, 19].” Comment 6: Please state the reference for the sentence “Although it is widely accepted that an appropriate warm-up programme should improve performance, more recent studies indicated that the 11+ programme does not improve players' performance acutely but may reduce sprinting and agility compared to a dynamic warm-up programme.” P.10 Comment 7: In the abstract the authors stated that the CG did not perform injury prevention studies, however in the methods section, the contrary is stated. Comment 7: Was static stretching really used? P.11 Comment 8: Please add further information of how the instructions to perform the 11+ and the M11+ were carried out. Comment 9: Data collection and supervision: How where the assistants “blinding each other”? Comment 10: Why was the “M. iliopsoas strengthening” and the “single-leg standing with a heel-to-toe movement cycle” selected? Can the authors support these choices with evidence? It would be great as the M11+ group showed few injuries. P.12 Comment 11: A table with Injury incidence/1000h and rate ratios for each group would enhance the manuscript. Comment 12: Further detail on injuries would also be of great interest for the study: (Fuller et al, 2006). p.13 Comment 13: The second manuscript from (Lopes et al.) is not in the references section. In the sentence extracted from other manuscripts as the numbered references are of other studies? p.14 Comment 14: “Neither F11+ nor M11+ could significantly reduce the risk of groin and hip injuries.” Can these stats be shown in a table? Comment 15: The paragraph below is very important, however the message is not clear. Please rephrase. “Neither F11+ nor M11+ could significantly reduce the risk of groin and hip injuries. In addition to the reasons mentioned above, they could not mitigate hip and groin injuries since they provided no specific exercise for groin muscles. This appears to be a noticeable gap, as up to 12% of subelite football injuries occur in the groin region [41]. Wahlan et al. suggested that using Copenhagen adductor exercises may fill this gap and would be fit for inclusion in the FIFA11+ programme, as it requires no specific equipment and has three levels of difficulties [41]. The better efficacy of the M11+ in preventing hip injuries, however, might be due to increasing the volume of hip dynamic stretch exercise, namely, hip-in, in addition to manipulating how core area muscles are being trained. “ P.15 Comment 16: Limitations In fact the study did not recruit the expected number of teams to manage a randomized sample. It is not clear that the authors did recognize this limitation. Comment 17: Was the trial registered in a clinical trials platform? ****** 6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: No Reviewer #2: No ******** [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0275545.r001
Revision 1
10 Aug 2022 Author Response Dear Editor, Thank you so much for your great eyes to our work and highlighting those important points. We believe that the points you have raised would greatly enhance the quality of the manuscript. Thus, we tried to follow them in full and revise the manuscript accordingly. More specifically, regarding the data availability policy, we have now uploaded a minimized dataset as per your request. you will find the URL and DOI: URL:www.kaggle.com/dataset/1f3df0f9ccf87f9dbeaca960baf76527376189128948699c4dec7eb056098834 https://doi.org/10.34740/KAGGLE/DSV/4054705 All means and standard deviations have already been mentioned in the manuscript. The changes we made based on your comments are highlighted in red throughout the manuscript. More importantly, regarding your following comment ‘’Viewing your abstract, we can see that it was previously published by Springer: "Al Attar, W.S.A., Soomro, N., Pappas, E. et al. How Effective are F-MARC Injury Prevention Programs for Soccer Players? A Systematic Review and Meta-Analysis. Sports Med 46, 205–217 (2016). https://doi.org/10.1007/s40279-015-0404-x" We believe that there must be a mistake simply because any part of this manuscript has not been published up to this point. Further, the link you referred belongs to a systematic review which was first appeared in the literature 6 years ago, whereas this project has only one year old. Reviewer #1: Dear authors, I believe they did a good job and deserve credit for that. The study is well designed, the introduction is robust, the methods are well explained and the discussion supports the results. However, the conclusion can and should be improved, and should be presented with practical applications for the coach. Furthermore, I believe that the limitations should be inserted at the end of the discussion. Response: Dear Reviewer, we thank you so much for your positive review and for the positive and useful comments. We revised the conclusion and added recommendations for practitioners and trainers. Additionally, we inserted the limitation at the end of the discussion. The changes we made based on your comments are highlighted in light brown. Reviewer #2: The proposed manuscript is very interesting and has a noteworthy objective. Congratulations to the authors. My suggestions follow below. Response: Dear Reviewer, we thank you very much for your positive feedback on our work and for the detailed, supportive and constructive comments. They are very helpful to improve the manuscript’s quality. Therefore, our effort was to integrate the comments throughout the manuscript accurately. The changes based on your comments are highlighted in light blue. P.8 Comment 1: Please rephase the “Background”, specifically “…the latter has potentially reduced compliance and implementation of the programme” Response: Thank you. We revised the background accordingly. Comment 2: Keywords: I suggest not repeating the keyword that already exists in the title to enhance search results. Response: Thank you very much. We removed the keywords that are already a part of the title Comment 3: “static stretches” in the warm-up? Or did the authors mean “dynamic stretches”? Response: Thank you very much for your great eyes to the important words. According to the reports of our research assistant who was visiting the CG, athletes indeed performed some static stretches within the warm-up phase, with each stretch lasting approximately 12 seconds. Comment 4: Is the discussion the conclusion in the abstract? Response: Thank you for your comment. We added a one-sentence conclusion to the abstract. P.9 Comment 4: I suggest rephrasing the sentence “It aims to tackle modifiable injury risk factors such as neuromuscular control, static and dynamic balance, and the hamstring/quadriceps strength ratio[8].” as they are not risk factors. They can be considered “key elements of effective injury prevention programmes…” Response: Thank you so much. We revised the sentence accordingly. Comment 5: Please rephrase the sentence “The latter, along with barriers such as prolonged duration, concerns regarding some exercises, and lack of a link to football-specific targets[14, 18], has been discussed as a potential reason for low compliance and poor implementation of the programme[14, 19].” Response: Thank you so much. We revised the sentence accordingly. Comment 6: Please state the reference for the sentence “Although it is widely accepted that an appropriate warm-up programme should improve performance, more recent studies indicated that the 11+ programme does not improve players' performance acutely but may reduce sprinting and agility compared to a dynamic warm-up programme.” Response: Thank you so much. We cited a suitable reference to support the sentence’s content. P.10 Comment 7: In the abstract the authors stated that the CG did not perform injury prevention studies, however in the methods section, the contrary is stated. Response: Thank you so much for your great eyes to the manuscript. The phrase ‘’without any’’ specific injury prevention exercises… was missing. We rewrote the sentence. Comment 7: Was static stretching truly used? Response: Well, it was used and, to my knowledge, is still being used even in some developed countries and on a roughly large scale, unfortunately. P.11 Comment 8: Please add further information of how the instructions to perform the 11+ and the M11+ were carried out. Response: Thank you. We would be glad to present further details here and in the manuscript. First, we instructed the trainer and players on how to perform the programmes. Furthermore, we provided the 11+ group with the 11+manual (it was already translated in Persian by IF-MARC, Iran branch of FIFA Medical Assessment and Research Centre) and asked them to familiarize themselves with the 11+. In addition, we provided them with the YouTube link to watch out the 11+ exercises. For the M11+, we provided the trainers and the players with a series of photo slides including all exercises embedded in the programme. Meanwhile, to assure accuracy of the application of the 11+, a research assistant was responsible for visiting the training sessions of the M11+ and F11+ groups and checking the implementation of the warm-up modalities. Comment 9: Data collection and supervision: How where the assistants “blinding each other”? Response: Thank you so much for highlighting these important points. We applied that approach to minimize any potential risk of bias during data collection. Three research assistants were responsible for their subsequent groups while having no idea about the study aims, the interventions, occurred injuries of the other groups, etc. They were only in touch with the research group leader and remained anonymous across the project. Comment 10: Why was the “M. iliopsoas strengthening” and the “single-leg standing with a heel-to-toe movement cycle” selected? Can the authors support these choices with evidence? It would be great as the M11+ group showed few injuries. Response: Thank you very much for your detailed and beneficial comments. We are pleased to briefly explain it for your perusal: The idea of strengthening M. iliopsoas muscles and single-leg standing with a heel-to-toe movement cycle and also modifying some core exercises comes from Janda’s approach, namely, the muscular chain, which is also known as upper/lower cross syndromes, as well as Shirley Sahrmann’s approach: Izraelski, J., Assessment and treatment of muscle imbalance: The Janda approach. The Journal of the Canadian Chiropractic Association, 2012. 56(2): p. 158. Sahrmann, S., D.C. Azevedo, and L. Van Dillen, Diagnosis and treatment of movement system impairment syndromes. Brazilian journal of physical therapy, 2017. 21(6): p. 391-399. P.12 Comment 11: A table with Injury incidence/1000 h and rate ratios for each group would enhance the manuscript. Response: Thank you for your suggestion. We appreciate your support for enhancing the manuscript and considering them all. In this case, however, as we already have three tables in the manuscript, we taught that having another table could be too much. Therefore, we just added a row to table two, including IIC rates. Comment 12: Further detail on injuries would also be of great interest for the study: (Fuller et al, 2006). Response: Thank you. We added additional information. p.13 Comment 13: The second manuscript from (Lopes et al.) is not in the references section. In the sentence extracted from other manuscripts as the numbered references are of other studies? Response: Thank you so much for highlighting that mistake. Following your comment, we went through the reference list and found some errors by the meaning of false matching the numbers and references. Thus, all references were updated and matched accurately. p.14 Comment 14: “Neither F11+ nor M11+ could significantly reduce the risk of groin and hip injuries.” Can these stats be shown in a table? Response: Thank you for your attention. Given the few injuries that occurred in the hip and groin, we considered them and reported all as thigh injuries. Comment 15: The paragraph below is very important, however the message is not clear. Please rephrase. “Neither F11+ nor M11+ could significantly reduce the risk of groin and hip injuries. In addition to the reasons mentioned above, they could not mitigate hip and groin injuries since they provided no specific exercise for groin muscles. This appears to be a noticeable gap, as up to 12% of subelite football injuries occur in the groin region [41]. Wahlan et al. suggested that using Copenhagen adductor exercises may fill this gap and would be fit for inclusion in the FIFA11+ programme, as it requires no specific equipment and has three levels of difficulties [41]. The better efficacy of the M11+ in preventing hip injuries, however, might be due to increasing the volume of hip dynamic stretch exercise, namely, hip-in, in addition to manipulating how core area muscles are being trained. Response: Thank you for your comment. We revised the paragraph and hope that the readers now can clearly follow the argumentation and get the message. P.15 Comment 16: Limitations In fact the study did not recruit the expected number of teams to manage a randomized sample. It is not clear that the authors did recognize this limitation. Response: Thank you. We revised the limitation and pointed out the lack of a recruiting sample in addition to the short monitoring period. Comment 17: Was the trial registered in a clinical trials platform? Response: Thank you. It was not registered Attachments Attachment Submitted filename: response to reviewers.docx https://doi.org/10.1371/journal.pone.0275545.r002
12 Sep 2022 Decision Letter - Rafael Franco Soares Oliveira, Editor PONE-D-22-14375R1Effects of the FIFA 11+ and a modified warm-up programme on injury prevention and performance improvement among youth male football players.PLOS ONE Dear Dr. Asgari, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. ==============================Dear authors, The authors made a great work in improving the work by following suggestion made by both reviewers. Reviewer 1 already recommend acception. Even so, I agree with the opinion of the second reviewers and for that reason, I suggest another round to improve the topic about static stretching being considered a good strategy for injury prevention. Thank you ============================== Please submit your revised manuscript by Oct 27 2022 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-emailutm_source=authorlettersutm_campaign=protocols. We look forward to receiving your revised manuscript. Kind regards, Rafael Franco Soares Oliveira Academic Editor PLOS ONE Journal Requirements: Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. Additional Editor Comments: Dear authors, The authors made a great work in improving the work by following suggestion made by both reviewers. Reviewer 1 already recommend acception. Even so, I agree with the opinion of the second reviewers and for that reason, I suggest another round to improve the topic about static stretching being considered a good strategy for injury prevention. Thank you [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #1: All comments have been addressed Reviewer #2: All comments have been addressed ******** 2. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Yes Reviewer #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: I Don't Know ****** 4. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: Yes ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: Yes ****** 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: Dear author, thank you for submitting the manuscript. I believe that the authors did a good job of reformulating the manuscript according to the reviewers' requests. In that sense, I have no further reservations about the manuscript. Reviewer #2: I thank the authors for their great effort in replying adequately to all the suggestion made. I have one final concern. I recommend a like a deeper discussion around the topic “static stretching” to be reflected in this manuscript. We understand that static stretching is not recommended to initiate sports practice. It reduces strength. How can the authors defend this modification to widely accepted injury prevention program. Please state this clearly in the manuscript. ****** 7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: No Reviewer #2: No ******** [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0275545.r003
Revision 2
16 Sep 2022 Author Response Dear respected editor/ reviewers On behalf of our research group, I do thank you so much again for your positive reviews and commentary on our work. We do believe that the comments you made have widely improved the quality of our paper, so we highly appreciate your efforts. Just to reflect well to the last comment provided by the second reviewer which is a kind of misunderstanding/miscommunication, I do refer to the first revision round where I clearly stated that based on the research assistant, the Control Group (CG) used some static stretches as part of their routine warm up before main training. So, there was no any kind of static stretches neither in 11+ nor in the modified 11+ and as you accurately mentioned, it has been scientifically proven that static stretches must not be used for warming up. To eliminate such misunderstanding, bellow you’ll find the original comments and the responses from the first revision round: Comment 3: “static stretches” in the warm-up? Or did the authors mean “dynamic stretches”? Response: Thank you very much for your great eyes to the important words. According to the reports of our research assistant who was visiting the CG, athletes indeed performed some static stretches within the warm-up phase, with each stretch lasting approximately 12 seconds. Comment 7: Was static stretching truly used? Response: Well, it was used and, to my knowledge, is still being used even in some developed countries and on a roughly large scale, unfortunately. Given that there is no other comments to be reflected, I assume that this clarification suffices and therefore, we did not provide any changes on the manuscript. Attachments Attachment Submitted filename: Response to the reviewers second round.docx https://doi.org/10.1371/journal.pone.0275545.r004
19 Sep 2022 Decision Letter - Rafael Franco Soares Oliveira, Editor Effects of the FIFA 11+ and a modified warm-up programme on injury prevention and performance improvement among youth male football players. PONE-D-22-14375R2 Dear Dr. Asgari, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Rafael Franco Soares Oliveira Academic Editor PLOS ONE Additional Editor Comments (optional): Dear authors, Congratulations on your work! After the clarification of the authors on the previous comments, I believe that this work can be accepted for publication. Thank you. Best regards Reviewers' comments: https://doi.org/10.1371/journal.pone.0275545.r005
Formally Accepted
22 Sep 2022 Acceptance Letter - Rafael Franco Soares Oliveira, Editor PONE-D-22-14375R2 Effects of the FIFA 11+ and a modified warm-up programme on injury prevention and performance improvement among youth male football players. Dear Dr. Asgari: I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department. If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org. If we can help with anything else, please email us at plosone@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Rafael Franco Soares Oliveira Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0275545.r006

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