Non-linear trends using the generalized additive models in physical and technical performances of the Chinese Super League players

Wei Zhang; Rancheng Tao; Fei Zhou; Changjing Zhou; Bo Gong

doi:10.1371/journal.pone.0307843

Peer Review History

Original SubmissionJanuary 6, 2024
23 Apr 2024 Decision Letter - Julio Alejandro Henriques Castro da Costa, Editor PONE-D-23-44027Non-linear trends using the generalized additive models in physical and technical performances of the Chinese Super League playersPLOS ONE Dear Dr. Zhou, 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 Jun 07 2024 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. 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The PLOS ONE style templates can be found at https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf 2. In the online submission form, you indicated that the datasets generated for this work can be accessed by contacting the corresponding author upon request. All PLOS journals now require all data underlying the findings described in their manuscript to be freely available to other researchers, either 1. In a public repository, 2. Within the manuscript itself, or 3. Uploaded as supplementary information. This policy applies to all data except where public deposition would breach compliance with the protocol approved by your research ethics board. If your data cannot be made publicly available for ethical or legal reasons (e.g., public availability would compromise patient privacy), please explain your reasons on resubmission and your exemption request will be escalated for approval. 3. 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 If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references.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. [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: Yes ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: Yes ****** 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: Yes ****** 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 Editor-in-Chief and Authors of the study, I appreciate the opportunity to review the paper titled "Non-linear trends using generalized additive models in physical and technical performances of the Chinese Super League players." In addition to the methodological rigor, I commend the robustness of the analysis carried out by considering different positions, various indicators, and their nonlinear behavior over time. Below, I offer a few suggestions for the article. L.88 – The acronym CSL has not been introduced previously. Please present the full name before using the acronym. L.113 to 119 – If possible, present this information in table format. Results - The figures appear to have very low quality, making it difficult to identify the variables. Therefore, we are left to "believe" in the values mentioned by the authors throughout the text. Since these figures represent the central results of the study, I suggest that the authors pay particular attention to them. Discussion – The study by Aquino et al. (2019) could also aid in discussing the differences found between teams playing with different playing systems. "Comparisons of ball possession, match running performance, player prominence, and team network properties according to match outcome and playing formation during the 2018 FIFA World Cup." Before finalizing the study, I suggest developing a paragraph presenting the limitations of the present work, as well as indications for future studies. Reviewer #2: Minor revisions. Introduction 1. In line 39, please use current references. 2. In line 42, change Barreira et al 3. In paragraph 2, any reference from the Asian Football Confederation leagues? 4. In line 88, add ‘Chinese Super League (CSL)’ Methods 1. In line 137, does the author analyse the physical and technical indicators of players in different positions? Discussion 1. Delete line 205-209, Repetitive 2. In the discussion, it will be good to compare your findings with other AFC league teams. 3. In line 229 and throughout the manuscript, change the word ‘more cleanly’ with other appropriate words. 4. Add the limitation of the study and practical implication paragraph. ****** 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: Yes: RAJA MOHAMMED FIRHAD RAJA AZIDIN ******** [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. Attachments Attachment Submitted filename: P1_reviewed.docx https://doi.org/10.1371/journal.pone.0307843.r001
Revision 1
26 Jun 2024 Author Response Response to Reviewer 1 comments Dear reviewer, Thank you for your time and valuable comments. We have provided a point-by-point response to each of your comments and suggestions and have made the appropriate changes to the manuscript. We believe the paper has improved significantly because of the review process. Comments 1：L.88 – The acronym CSL has not been introduced previously. Please present the full name before using the acronym. Response: Thank you for your valuable feedback regarding the use of the acronym "CSL" in our manuscript. We have carefully considered your suggestion and have made the necessary adjustments. Specifically, we have introduced the full name "Chinese Super League (CSL)" at its first mention in lines 67–70, as follows: "Similarly, research by Zhou et al. on the Chinese Super League (CSL) reveals that from 2012 to 2017, there was a notable enhancement in high-intensity play and offensive actions, illustrating an increase in both physical and technical demands across different playing positions." We appreciate your attention to detail and believe this change enhances the clarity and readability of our manuscript. Comments 2：L.113 to 119 – If possible, present this information in table format. Response: Thank you for your insightful suggestion regarding the presentation of information in lines 113 to 119. We have taken your advice and transformed this section into a table format to enhance clarity and readability. The table has been added in lines 629-632 of the manuscript. We believe this modification improves the overall presentation of the data and appreciate your guidance. Comments 3：Results - The figures appear to have very low quality, making it difficult to identify the variables. Therefore, we are left to "believe" in the values mentioned by the authors throughout the text. Since these figures represent the central results of the study, I suggest that the authors pay particular attention to them. Response: Thank you for your feedback on the quality of the figures in our manuscript. We understand the importance of clear and high-quality visual representations of our results. The original figures in our submission are indeed prepared at 300 DPI resolution to ensure clarity and precision. However, it appears that the process of uploading the manuscript may have caused a compression issue, affecting the image quality. We apologize for any inconvenience this may have caused. To resolve this, we will re-upload the figures to ensure they are displayed at their intended quality. We appreciate your understanding and your attention to detail, and we will ensure that the figures meet the highest standards for clarity in the revised submission Comments 4：Discussion – The study by Aquino et al. (2019) could also aid in discussing the differences found between teams playing with different playing systems. "Comparisons of ball possession, match running performance, player prominence, and team network properties according to match outcome and playing formation during the 2018 FIFA World Cup." Response: Thank you for your valuable suggestion regarding the inclusion of the study by Aquino et al. (2019) in our discussion. We have incorporated this reference into our manuscript to enhance the discussion on the differences found between teams using various playing systems. Specifically, we have added the following content in lines 287-295: "According to our data, CMs in the 4-2-3-1 formation have shown nonlinear growth trends in the number of passes and ball retention percentage from the 2015 to 2021 seasons. This is in line with the findings of Aquino et al. [37], who observed that teams employing a 4-2-3-1 formation tended to dominate possession and displayed enhanced network properties, suggesting better team coordination and player interaction. Furthermore, it is widely acknowledged that CMs play a crucial role in coordinating offensive actions [33, 38]. Thus, this trend may also be attributed to build-up play, which allows CMs in the 4-2-3-1 formation to establish a connection between the defensive line and the forward line through passing." We believe this addition strengthens the discussion by providing a comparative perspective and supporting our findings with relevant literature. Thank you again for your insightful feedback. Comments 5：Before finalizing the study, I suggest developing a paragraph presenting the limitations of the present work, as well as indications for future studies. Response: Thank you for your insightful suggestion to include a discussion on the limitations of our study and indications for future research. We have developed a paragraph to address these aspects and have included it in lines 417-439 of the manuscript: Limitations：It is important to acknowledge certain limitations within this study. Although generalized additive models (GAMs) provide robust insights into non-linear trends, the results may still be influenced by external factors such as player fitness, match intensity, and weather conditions that were not controlled in this study. Additionally, the exclusion of goalkeeper data and matches with red cards or formation changes might limit the generalizability of our findings across all match scenarios in the Chinese Super League. Lastly, while we have extensive data across several seasons, the evolving nature of sports analytics and data collection might mean that newer methods could provide different insights that were not available at the time of this study. Practical Implications ：The findings from this study have significant practical implications for coaching and tactical strategy in soccer. By understanding the non-linear evolution of player performance across different tactical formations, coaches can tailor training programs more effectively to meet the demands of specific positions and match situations. For example, the increased high-speed running and sprint distances identified for forwards in certain formations can inform more focused conditioning work to enhance players' endurance and speed. Additionally, the variations in technical performance, such as passing and ball retention across different formations, highlight the need for adaptable tactical training that prepares players for various strategic roles. This study thereby supports the development of targeted strategies that can optimize team performance and adaptability in competitive matches. We believe these additions provide a comprehensive view of our study's scope and offer valuable directions for future research. Response to Reviewer 2 comments Dear reviewer, Thank you for your time and valuable comments. We have provided a point-by-point response to each of your comments and suggestions and have made the appropriate changes to the manuscript. We believe the paper has improved significantly because of the review process. Your thoughtful insights and constructive feedback have been instrumental in refining our work, and we are grateful for your dedication to the review process. Your expertise has undoubtedly contributed to the overall quality of the manuscript. Introduction Comments 1：In line 39, please use current references. Response：Thank you for your suggestion to use current references in line 39. We have updated the manuscript to include recent literature to support our statements. Specifically, we have cited the following references: Lago-Peñas, C., et al., Evolution of physical and technical parameters in the Spanish LaLiga 2012-2019. Science and Medicine in Football, 2023. 7(1): p. 41-46. Allen, T., et al., Running more than before? The evolution of running load demands in the English Premier League. International Journal of Sports Science & Coaching, 2024. 19(2): p. 779-787 We believe these recent references enhance the relevance and credibility of our study. Comments 2：In line 42, change Barreira et al Response：Thank you for your suggestion to update the reference in line 42. We have made the necessary changes in the manuscript to include the following citation: Zhou, C., et al., Long-term influence of technical, physical performance indicators and situational variables on match outcome in male professional Chinese soccer. Journal of Sports Sciences, 2021. 39(6): p. 598-. Comments 3：In paragraph 2, any reference from the Asian Football Confederation leagues? Response：Thank you for your suggestion to include references from the Asian Football Confederation leagues in paragraph 2. We have addressed this by incorporating the following reference in lines 67-70: "Similarly, research by Zhou et al. [16] on the Chinese Super League (CSL) reveals that from 2012 to 2017, there was a notable enhancement in high-intensity play and offensive actions, illustrating an increase in both physical and technical demands across different playing positions." We believe this addition enriches the context of our study by providing relevant insights from the Asian Football Confederation leagues. Comments 4：In line 88, add ‘Chinese Super League (CSL)’ Response：Thank you for your suggestion to include the full name "Chinese Super League (CSL)" in line 88. We have made this adjustment at the first mention of the league in lines 67-70, as follows: "Similarly, research by Zhou et al. [16] on the Chinese Super League (CSL) reveals that from 2012 to 2017, there was a notable enhancement in high-intensity play and offensive actions, illustrating an increase in both physical and technical demands across different playing positions." Methods Comments 5: In line 137, does the author analyse the physical and technical indicators of players in different positions? Response：Thank you for your insightful question regarding line 137. Our study indeed analyzes the physical and technical indicators of players in different positions. Specifically, we have examined the non-linear evolution of these indicators for central defenders, fullbacks, central midfielders, wide midfielders, and forwards across various formations from the 2015 to 2021 seasons in the Chinese Super League (CSL). We employed generalized additive models (GAMs) to analyze these trends, focusing on metrics such as total distance covered, sprint distance, number of sprints, high-speed running, ball retention percentage, pass success rate, and more. These analyses provide a comprehensive understanding of how physical and technical performances have evolved position-specifically under different tactical formations. We hope this clarifies our approach and analysis. Thank you for your valuable feedback. Discussion Comments 6: Delete line 205-209, Repetitive Response: Thank you for your careful review of our manuscript. We have addressed your suggestion and deleted the repetitive content in lines 205-209. We appreciate your attention to detail and believe this change enhances the clarity of our manuscript. Comments 7: In the discussion, it will be good to compare your findings with other AFC league teams. Response: Thank you for your suggestion to compare our findings with other AFC league teams in the discussion. Due to the limited research available on the evolution of running and technical performance trends of players in Asian leagues, we have made a comparison with the Second Division of Japanese Professional Football (J2 League) in lines 235-237 of our manuscript: "Previous research on the Second Division of Japanese Professional Football indicates that the total running distance of players has shown a decreasing trend over three seasons [31]." We recognize that this comparison is somewhat limited and appreciate any further suggestions you may have to enhance this section of our manuscript. Thank you for your valuable feedback and understanding. Comments 7: In line 229 and throughout the manuscript, change the word ‘more cleanly’ with other appropriate words. Response: Thank you for your suggestion to replace the phrase "more cleanly" with more appropriate words throughout the manuscript. We have made the necessary changes in lines 228-229 and 270-272 as follows: "These results may suggest that players play soccer with more tactical discipline and less aggressiveness [29, 30]." "The diminishing challenge faced by FBs, similar to what has been observed among CDs, might indicate a shift towards a less aggressive style of play among players [29, 30]." We believe these revisions improve the clarity and precision of our language. Comments 7: Add the limitation of the study and practical implication paragraph Response: Thank you for your insightful suggestion to include a discussion on the limitations of our study and indications for future research. We have developed a paragraph to address these aspects and have included it in lines 417-439 of the manuscript: Limitations：It is important to acknowledge certain limitations within this study. Although generalized additive models (GAMs) provide robust insights into non-linear trends, the results may still be influenced by external factors such as player fitness, match intensity, and weather conditions that were not controlled in this study. Additionally, the exclusion of goalkeeper data and matches with red cards or formation changes might limit the generalizability of our findings across all match scenarios in the Chinese Super League. Lastly, while we have extensive data across several seasons, the evolving nature of sports analytics and data collection might mean that newer methods could provide different insights that were not available at the time of this study. Practical Implications ：The findings from this study have significant practical implications for coaching and tactical strategy in soccer. By understanding the non-linear evolution of player performance across different tactical formations, coaches can tailor training programs more effectively to meet the demands of specific positions and match situations. For example, the increased high-speed running and sprint distances identified for forwards in certain formations can inform more focused conditioning work to enhance players' endurance and speed. Additionally, the variations in technical performance, such as passing and ball retention across different formations, highlight the need for adaptable tactical training that prepares players for various strategic roles. This study thereby supports the development of targeted strategies that can optimize team performance and adaptability in competitive matches. We believe these additions provide a comprehensive view of our study's scope and offer valuable directions for future research. Attachments Attachment Submitted filename: Point-by-point response to reviewers file.docx https://doi.org/10.1371/journal.pone.0307843.r002
12 Jul 2024 Decision Letter - Julio Alejandro Henriques Castro da Costa, Editor Non-linear trends using the generalized additive models in physical and technical performances of the Chinese Super League players PONE-D-23-44027R1 Dear Dr. Zhou, 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 will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, 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, Julio Alejandro Henriques Castro da Costa Academic Editor PLOS ONE Additional Editor Comments (optional): 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 #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 #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #2: Yes ****** 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 #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 #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 #2: All required comments, questions have been answered and that all responses meet expectations and, formatting specifications. ****** 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 #2: Yes: RAJA MOHAMMED FIRHAD BIN RAJA AZIDIN ******** https://doi.org/10.1371/journal.pone.0307843.r003
Formally Accepted
17 Jul 2024 Acceptance Letter - Julio Alejandro Henriques Castro da Costa, Editor PONE-D-23-44027R1 PLOS ONE Dear Dr. Zhou, I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team. At this stage, our production department will prepare your paper for publication. This includes ensuring the following: * All references, tables, and figures are properly cited * All relevant supporting information is included in the manuscript submission, * There are no issues that prevent the paper from being properly typeset If revisions are needed, the production department will contact you directly to resolve them. If no revisions are needed, you will receive an email when the publication date has been set. At this time, we do not offer pre-publication proofs to authors during production of the accepted work. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few weeks to review your paper and let you know the next and final steps. Lastly, 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 customercare@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. Julio Alejandro Henriques Castro da Costa Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0307843.r004

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