Effects of Sidestep Exercise with Elastic Bands on Multidirectional Speed Abilities and Navicular Drop in Young Male Football Players: A Randomized Cross-Over Trial
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsI am grateful for the opportunity to review this article, which aligns with my research interests. The observations presented here do not diminish the efforts of the authors or the potential of the subject. Instead, they pertain to the technical and scientific status of the subject as it currently stands.
The question is both original and well-defined, and the results can contribute to the advancement of current knowledge. However, it is important to exercise caution when interpreting the results, since it is not possible to extrapolate them to other sporting activities or to female subjects.
Specific comments: Despite the limitations, the article presents an interesting opportunity to expand information about the context. Nevertheless, it is imperative to take into account a number of variables:
Title: The title is clear and expresses conformity with the study proposal.
The Abstract is written in a manner that is conducive to comprehension, and it provides a clear overview of the study's methodology. However, it would be a logical addition to include the statistical results and the average age of the participants.
The Introduction section is competently written and effectively guides the reader towards the central issue under discussion. However, the paragraph on lines 54-57 (This temporary...speed abilities) would benefit from the incorporation of a theoretical reference.
It is imperative that a superior reference is provided for the pilot studies referenced between lines 63 and 65. Have these studies been published in a scholarly journal? Are they specific to a laboratory that has not yet published them? Please provide clarification.
Material and Methods
It is suggested that the order be reversed, with the presentation of the “Participants and Ethics” preceding that of the “Experimental approach to the problem.
Experimental Approach to the Problem
The paragraph between lines 79 and 82 states that "During the following 3 weeks, one group carried out the experimental training protocol three days a week in addition to their regular training sessions, while the other continued with their regular football training sessions.After the first 3 weeks, the experimental role was reversed."Despite the understanding that a crossover design has this dynamic, the question must be asked whether a washout time between interventions was necessary. In the absence of such a period, it is reasonable to hypothesise that the initial intervention may have influenced the group that subsequently served as the control. In this context, it is proposed that the study include the inversion of groups without a minimum wash-out period as a limitation.
Participants
Given the inclusion of the U14 and U16 categories within the study, it is imperative to ascertain their maturational status, as this has the capacity to influence their response to training and physical interventions.
Besides, it is imperative to incorporate a more comprehensive set of information concerning the players, including the duration of their training experience, their experience in competitive play, and the specific positions they play.
Procedures
It is recommended that a figure be incorporated which encompasses the Lateral-step exercise and the linear and multidirectional sprinting tests.
Results:
The results are well presented and described.
Discussion:
The discussion provides good insights and reflections on the findings presented.
Nevertheless, the paragraphs commencing on line 213 and 247 are excessively protracted. It would be advantageous to divide the information into a greater number of paragraphs in order to facilitate the reader's comprehension and interpretation.
Besides, in order to enhance the quality of the discussion, it would be advisable to incorporate additional bibliographic references.
With regard to limitations (line 276), this study argues that the issue of application to other sports and the failure to extrapolate the data obtained to the female sex are necessarily limitations, when in fact they are not. Please review it.
Conclusions: The conclusion is presented in a clear and well-written manner, with a clear reference back to the initial aims. Nevertheless, it would be worthwhile to incorporate a section on potential practical applications at the end of the text.
References: Most of them are current and relevant to the topic. However, it is conceivable that some of these could be substituted with more contemporary ones.
Author Response
Point-by-point response to the comments of the reviewers
Paper Title: Effects of Sidestep Exercise with Elastic Bands Training on Multidirectional Speed Abilities and Navicular-Drop in Young Male Football Players
We appreciate the helpful comments of Reviewers. In order to clarify how we have responded to the reviewer, we have cut-and-pasted each comment below, responded to the comment and then explained how the comment has been accommodated in the revised manuscript. The changes in the revised manuscript are indicated in red font and English changes are provided in yellow. Where the comment raised by the Reviewer could not been accommodated within the revised manuscript, we have endeavoured to clearly explain why we did not incorporate his/her suggestions.
Reviewer #1: GENERAL COMMENTS:
I am grateful for the opportunity to review this article, which aligns with my research interests. The observations presented here do not diminish the efforts of the authors or the potential of the subject. Instead, they pertain to the technical and scientific status of the subject as it currently stands.
The question is both original and well-defined, and the results can contribute to the advancement of current knowledge. However, it is important to exercise caution when interpreting the results, since it is not possible to extrapolate them to other sporting activities or to female subjects.
Answer to reviewer: Thank you for your comment.
Title:
Title: The title is clear and expresses conformity with the study proposal.
Answer to reviewer: Thank you for your comment.
Abstract:
The Abstract is written in a manner that is conducive to comprehension, and it provides a clear overview of the study's methodology. However, it would be a logical addition to include the statistical results and the average age of the participants.
Answer to reviewer: Thank you for your comment. We have included them.
Changes made in the manuscript:
The aims of the current study were to assess the effect of including the lateral step or sidestep exercise with elastic bands on multidirectional speed abilities (linear, change of direction, and curve sprinting) and navicular drop and to know the impact of navicular drop changes on multidirectional sprinting changes in young male football players. Thirty-two male young football players (age: 14.7 ± 0.82) were randomly divided into group A (n=16) or group B (n=16). Using a crossover design trial (AB BA), a group performed 3 sets of 6 repetitions per side in the lateral-step exercise with elastic bands attached in a low vector, three days per week plus their regular training sessions, while the other continued with their regular football training sessions, during the first 3 weeks, changing the roll during the next 3 weeks of the intervention. Pre-intervention, three and six weeks after the beginning of the intervention, a navicular drop test, a 10-m linear sprint test, a multiple change of direction test (V-cut), and a curvilinear sprinting test were assessed. The sidestep exercise with elastic bands significantly improved the ability to sprinting multidirectionally in only three weeks of training (p<0.05, n2=0.56 to 0.74), and there was a trend in the impact of multidirectional sprinting performance through those changes reported in the navicular drop test (r= -0.23 to 0.45).
Introduction:
The Introduction section is competently written and effectively guides the reader towards the central issue under discussion. However, the paragraph on lines 54-57 (This temporary...speed abilities) would benefit from the incorporation of a theoretical reference.
Answer to reviewer: Thank you for your comment. We have amended it accordingly.
Changes made in the manuscript: We introduced this reference: 19. McKeon PO, Hertel J, Bramble D, Davis I. The foot core system: a new paradigm for understanding intrinsic foot muscle function. Br J Sports Med 49(5): 290, 2015.
It is imperative that a superior reference is provided for the pilot studies referenced between lines 63 and 65. Have these studies been published in a scholarly journal? Are they specific to a laboratory that has not yet published them? Please provide clarification.
Answer to reviewer: Thank you for your comment. They are specific to our laboratory and such results have not yet published. We have amended accordingly in the text.
Changes made in the manuscript:
As we have seen in non-published pilot studies, a lateral step movement using a lateral and low force-vector through an elastic band increases the intrinsic foot muscle activation measured through EMG.
Material and Methods
It is suggested that the order be reversed, with the presentation of the “Participants and Ethics” preceding that of the “Experimental approach to the problem.
Answer to reviewer: Thank you. Comment acknowledged.
The paragraph between lines 79 and 82 states that "During the following 3 weeks, one group carried out the experimental training protocol three days a week in addition to their regular training sessions, while the other continued with their regular football training sessions. After the first 3 weeks, the experimental role was reversed. "Despite the understanding that a crossover design has this dynamic, the question must be asked whether a washout time between interventions was necessary. In the absence of such a period, it is reasonable to hypothesise that the initial intervention may have influenced the group that subsequently served as the control. In this context, it is proposed that the study include the inversion of groups without a minimum wash-out period as a limitation.
Answer to reviewer: Thank you, Comment acknowledged.
Changes made in the manuscript:
We did not include a washout period between two experimental phases. Eligible players were randomized in a 1:1 allocation to group A (n=16) or group B (n=16). Lastly, the absence of washout time between interventions period, it is reasonable to hypothesise that the initial intervention may have influenced the group that subsequently served as the control.
Participants:
Given the inclusion of the U14 and U16 categories within the study, it is imperative to ascertain their maturational status, as this has the capacity to influence their response to training and physical interventions.
Besides, it is imperative to incorporate a more comprehensive set of information concerning the players, including the duration of their training experience, their experience in competitive play, and the specific positions they play.
Answer to reviewer: Thank you for your comment. We have amended accordingly in the text.
Changes made in the manuscript:
They training experience is 8.2 ±1.1 y , their experience in competitive play is 7.7 ± 1.5 y, and the specific positions they play are 5 fullback, 6 central defender, 7 midfielders, 4wingers, 4 playmakers, 6 strikers.
Methods:
It is recommended that a figure be incorporated which encompasses the Lateral-step exercise and the linear and multidirectional sprinting tests.
Answer to reviewer: Thank you for your comment. The exercise is illustrated in figure 2. Sprint and change of direction tests are the most commonly used in the literature, so they have been represented on multiple occasions, and of course we have referenced them in this article. We do not believe that this will increase the understanding of the article, and we would exceed the number of possible images. If you think it is essential for the publication of the article, we can include it without problem.
Methods:
The results are well presented and described.
Answer to reviewer: Thank you for your comment.
Discussion
The discussion provides good insights and reflections on the findings presented.
Nevertheless, the paragraphs commencing on line 213 and 247 are excessively protracted. It would be advantageous to divide the information into a greater number of paragraphs in order to facilitate the reader's comprehension and interpretation.
Answer to reviewer: Thank you for your comment. We have divided the paragraph to facilitate the reading.
Besides, in order to enhance the quality of the discussion, it would be advisable to incorporate additional bibliographic references.
Answer to reviewer: Thank you for your comment. We have amended it accordingly.
With regard to limitations (line 276), this study argues that the issue of application to other sports and the failure to extrapolate the data obtained to the female sex are necessarily limitations, when in fact they are not. Please review it.
Answer to reviewer: Thank you for your comment. We have amended it accordingly.
Changes made in the manuscript:
It is essential to acknowledge some limitations in the present study. Specifically, there is a lack of GPS to daily monitor training load. It does not allow to verify whether the training load has been the same for all the players who participated in this study. However, all participants had an identical temporal exposure to football training, using similar space-time structures during such period. Lastly, the absence of washout time between interventions period, it is reasonable to hypothesise that the initial intervention may have influenced the group that subsequently served as the control.
Conclusions
The conclusion is presented in a clear and well-written manner, with a clear reference back to the initial aims. Nevertheless, it would be worthwhile to incorporate a section on potential practical applications at the end of the text.
Answer to reviewer: Thank you for your comment. We have included a practical applications section.
Changes made in the manuscript:
The current results provide a fascinating overview that includes an easily implemented exercise within practice routines to prepare your players for training and to improve multidirectional abilities. All clubs can access such material to improve the quality of activations, increase the feedforward mechanism, minimizing the injury risk on any pitch with the specific football shoes used during games and training.
References
Most of them are current and relevant to the topic. However, it is conceivable that some of these could be substituted with more contemporary ones.
Answer to reviewer: Thank you for your comment. We have included some contemporary references.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis is a crossover design trial (AB BA) evaluating the effects of an elastic band resisted lateral-step exercise on football-related physical performance measures and navicular foot drop in young players. The reporting of this trial would strongly benefit from adhering to the recommendations of the CONSORT initiative for reporting crossover trials (e.g., include in the title the study design, report the washout period and crossover effects, flow diagram of the trial, randomization technic, blinding procedures etc.). You can find them here (https://www.equator-network.org/reporting-guidelines/consort-2010-statement-extension-to-randomised-crossover-trials/). This will strengthen the article. Throughout the manuscript the symbol of degree (º) should be reviewed as it is not correct. The citation style changes at times, therefore, also needs amendments. Importantly, the instrument and technical procedures (e.g., bony landmarks used) to assess navicular drop needs to be reported so that we can better interpret the results shown in Table 1. You report mean differences of less than 1 mm in NDR/L. Maybe the units are not correct (m instead of cm?)… For all measures, report, considering past studies in the literature, the measurement error associated with each of them (e.g., SEM [standard error of the measurement], MDC [minimal detectable change) so that we can better interpret your findings, i.e., what may be the effects of intervention versus what may be the effects of measurement error from multiple measurements throughout time. For electronic instruments (e.g., photoelectric cells) provide the calibrations procedures.
Title: Consider adhering to CONSORT for crossover design trials recommendations and include the study design
Abstract: Avoid acronyms (COD). Also, provide pre-post differences with 95% confidence intervals, effect size and p-value in lines 24 and 25 as many readers only read the abstract.
Line 31: I would remove “often”
Line 54: Sprints during walking? Improve this sentence.
Lines 63–64: Provide the citations/references of these pilot studies you referring to, a good summary of the procedures (e.g., how was foot muscle activation studied [EMG?])
Line 74: were recruited to voluntarily participate instead of were voluntarily recruited to participate? Also, state the dates when study has initiated and completed.
Provide the flowchart of the participants and the study design.
Line 75: provide details of the randomization process.
Figure 1: why the mask? And where is the elastic band attached? Please inform.
Lines 118:126: how was elastic band resistance selected? Was there any elastic band exercise progression during the 3 weeks? Please provide the manufacturer of the elastic bands. Also, given that the protocol was applied during warm-up for football practice involving all players, inform what measures were taken to prevent contamination between groups.
Lines 127–17: what was the instrument used to measure distance? Was any bony eminence landmark of the navicular used to standardize the measurement? Please inform. Who measured? Inform about the blinding procedures…
Lines 157–176: inform about the threshold value for decision in inferential statistics (p-value). Also inform readers better how you ANOVA design accounts for the crossover effect of intervention.
Lines 179–192: Provide the exact p-values
Table1: If I’m reading correctly, in NDR and NDL the mean differences between seated and standing is less than 1 mm, considering the units (cm). I’m curious about the instrument authors have used to measure navicular drop…
Line 215–216: considering what comes next, the sentence “Previous studies (9,14,16,22,24,26) have found various adaptations (ES= -0.07 to 1.79) related to multidirectional ability” appears incomplete.
Discuss the crossover effect and the washout implications in your results and the expected or unexpected differences between your groups A and B.
Line 264: revise the “who”.
References 19 and 20 are repeated.
Comments on the Quality of English LanguageThere are some grammatical errors in the text. I provide some examples for improvement but authors should check the text with a native with academic/scientific experience.
Author Response
Point-by-point response to the comments of the reviewers
Paper Title: Effects of Sidestep Exercise with Elastic Bands Training on Multidirectional Speed Abilities and Navicular-Drop in Young Male Football Players
We appreciate the helpful comments of Reviewers. In order to clarify how we have responded to the reviewer, we have cut-and-pasted each comment below, responded to the comment and then explained how the comment has been accommodated in the revised manuscript. The changes in the revised manuscript are indicated in red font and English changes are provided in yellow. Where the comment raised by the Reviewer could not been accommodated within the revised manuscript, we have endeavoured to clearly explain why we did not incorporate his/her suggestions.
Reviewer #2:
Comments and Suggestions for Authors
This is a crossover design trial (AB BA) evaluating the effects of an elastic band resisted lateral-step exercise on football-related physical performance measures and navicular foot drop in young players. The reporting of this trial would strongly benefit from adhering to the recommendations of the CONSORT initiative for reporting crossover trials (e.g., include in the title the study design, report the washout period and crossover effects, flow diagram of the trial, randomization technic, blinding procedures etc.). You can find them here (https://www.equator-network.org/reporting-guidelines/consort-2010-statement-extension-to-randomised-crossover-trials/). This will strengthen the article. Throughout the manuscript the symbol of degree (º) should be reviewed as it is not correct. The citation style changes at times, therefore, also needs amendments. Importantly, the instrument and technical procedures (e.g., bony landmarks used) to assess navicular drop needs to be reported so that we can better interpret the results shown in Table 1. You report mean differences of less than 1 mm in NDR/L. Maybe the units are not correct (m instead of cm?)… For all measures, report, considering past studies in the literature, the measurement error associated with each of them (e.g., SEM [standard error of the measurement], MDC [minimal detectable change) so that we can better interpret your findings, i.e., what may be the effects of intervention versus what may be the effects of measurement error from multiple measurements throughout time. For electronic instruments (e.g., photoelectric cells) provide the calibrations procedures.
Answer to reviewer: Thank you for your comment. We have considered your recommendations within the main text.
Title: Consider adhering to CONSORT for crossover design trials recommendations and include the study design
Answer to reviewer: Thank you for your comment. We have adapted the title.
Changes made in the manuscript:
Effects of Sidestep Exercise with Elastic Bands Training on Multidirectional Speed Abilities and Navicular-Drop in Young Male Football Players: a randomized cross-over trial.
Abstract: Avoid acronyms (COD). Also, provide pre-post differences with 95% confidence intervals, effect size and p-value in lines 24 and 25 as many readers only read the abstract.
Answer to reviewer: Thank you for your comment. We have included the ES and p-values as avoided acronyms like COD.
Changes made in the manuscript:
Abstract: The aims of the current study were to assess the effect of including the lateral step or sidestep exercise with elastic bands on multidirectional speed abilities (linear, change of direction, and curve sprinting) and navicular drop and to know the impact of navicular drop changes on multidirectional sprinting changes in young male football players. Thirty-two male young football players (age: 14.7 ± 0.82) were randomly divided into group A (n=16) or group B (n=16). Using a crossover design trial (AB BA), a group performed 3 sets of 6 repetitions per side in the lateral-step exercise with elastic bands attached in a low vector, three days per week plus their regular training sessions, while the other continued with their regular football training sessions, during the first 3 weeks, changing the roll during the next 3 weeks of the intervention. Pre-intervention, three and six weeks after the beginning of the intervention, a navicular drop test, a 10-m linear sprint test, a multiple change of direction test (V-cut), and a curvilinear sprinting test were assessed. The sidestep exercise with elastic bands significantly improved the ability to sprinting multidirectionally in only three weeks of training (p<0.05, n2=0.56 to 0.74), and there was a trend in the impact of multidirectional sprinting performance through those changes reported in the navicular drop test (r= -0.23 to 0.45).
Line 31: I would remove “often”
Answer to reviewer: Thank you for your comment. We have removed “often”.
Line 54: Sprints during walking? Improve this sentence.
Answer to reviewer: Thank you for your comment. We have deleted some parts of the sentence to improve it.
Changes made in the manuscript:
For example, Okamura et al. (2020) (19) show that for individuals with flat feet, an effective correction of the alignment of the foot and the temporal parameters of the kinematics of the foot occurred while sprinting or changing direction.
Lines 63–64: Provide the citations/references of these pilot studies you referring to, a good summary of the procedures (e.g., how was foot muscle activation studied [EMG?])
Answer to reviewer: Thank you for your comment. Those studies we are referring to are non-published. Furthermore, foot muscle activation was measured through EMG.
Changes made in the manuscript:
As we have seen in non-published pilot studies, a lateral step movement using a lateral and low force-vector through an elastic band increases the intrinsic foot muscle activation measured through EMG.
Line 74: were recruited to voluntarily participate instead of were voluntarily recruited to participate? Also, state the dates when study has initiated and completed.
Answer to reviewer: Thank you for your comment. We have amended it accordingly.
Changes made in the manuscript:
Using a controlled, randomized, and crossover design tial (AB BA), a group of trained young male football players (U-14 to U-16) were recruited to voluntarily participate in the current study from 18th December to 9th March. We did not include a washout period between two experimental phases. Eligible players were randomized in a 1:1 allocation to group A (n=16) or group B (n=16).
Provide the flowchart of the participants and the study design.
Answer to reviewer: Thank you for your comment. We have included a flowchart.
Changes made in the manuscript:
Line 75: provide details of the randomization process.
Answer to reviewer: Thank you for your comment. We have provided details of the randomization process.
Changes made in the manuscript:
Using a controlled, randomized, and crossover design trial (AB BA), a group of trained young male football players (U-14 to U-16) were randomly allocated (https://www.randomizer.org/) in two groups and were recruited to voluntarily participate in the current study from 18th December to 9th March.
Figure 1: why the mask? And where is the elastic band attached? Please inform.
Answer to reviewer: Thank you for your comment. The mask is not relevant as we used a picture from COVID. The mask was not used through the intervention. The elastic band was attached attached to the waist with a belt and in a low vector anchored to the floor.
Changes made in the manuscript:
“…an elastic band (Sanctband, Super Loop Purple; 4.76mm thick x 25.4mm wide x 1000mm long; 13.61KGF; Sanct Japan Co., Ltd.) attached to the waist with a belt and in a low vector anchored to the floor…”
Lines 118:126: how was elastic band resistance selected? Was there any elastic band exercise progression during the 3 weeks? Please provide the manufacturer of the elastic bands. Also, given that the protocol was applied during warm-up for football practice involving all players, inform what measures were taken to prevent contamination between groups.
Answer to reviewer: Thank you for your comment. We have provided the manufacturer of the elastic band. No modification was included during the 3-week period. While the experimental group performed their activation, the group that did not perform it performed rounds of 6 attackers and 2 defenders.
Changes made in the manuscript:
“While the experimental group performed their activation, the group that did not perform it performed rondo (pig in the middle) of 6 attackers and 2 defenders.”
“…an elastic band (Sanctband, Super Loop Purple; 4.76mm thick x 25.4mm wide x 1000mm long; 13.61KGF; Sanct Japan Co., Ltd.) attached to the waist with a belt and in a low vector anchored to the floor…”
Lines 127–17: what was the instrument used to measure distance? Was any bony eminence landmark of the navicular used to standardize the measurement? Please inform. Who measured? Inform about the blinding procedures…
Answer to reviewer: Thank you for your comment. We amended it accordingly.
Changes made in the manuscript:
Brody’s method was used to assess navicular drop as proposed by Adhikari et al., 2018 (1). The distance from the position of the navicular bone of the foot to the ground was measured in a sitting position (i.e. unloading) by passively placing the foot in a neutral position with a 90o angle at the hip, knee and ankle, and in a standing position (i.e. loading). The tester repeated the measurement three times and record the average value of these measurements (Allen & Glasoe, 2000). A Vernier TM height caliper (Mitutoyo American Corporation, Mitotoyo, Japan) was used to calculate the navicular drop, the difference between the height of the navicular drop at rest (unloading) minus the height of the navicular drop under loading was used (1, 11). A decrease in this value was interpreted as a smaller drop of the navicular bone under loading and therefore a maintenance of the plantar arch by the intrinsic musculature of the foot. The measurement was carried out on both the right (NDR) and left (NDL) legs by the same evaluator in all participants. Previos studies revealed strong intratester reliability (ICC 2,1 = 95) and precision of measurement (SEM = .73 mm) (11).
Lines 157–176: inform about the threshold value for decision in inferential statistics (p-value). Also inform readers better how you ANOVA design accounts for the crossover effect of intervention.
Answer to reviewer: Thank you for your comment. We have amended accordingly.
Changes made in the manuscript:
A 3 (1, 2, and 3 time-points) x 2 (Group A and Group B) repeated-measures ANOVA was developed to determine the effects of the intervention period through a crossover design. If the ANOVA was significant (p<0.05) (time, group, group-time interaction or time-group interaction), a Bonferroni’s correction to post-hoc comparisons was conducted.
Lines 179–192: Provide the exact p-values.
Answer to reviewer: Thank you for your comment. We have amended it accordingly.
Changes made in the manuscript:
A significantly (p<0.05) greater performance was found in both groups (i.e., group effect) in NDR (n2=0.41, p=0.001), curve sprinting to the right (CSR) (n2=0.12, p=0.049) and to the left (CSL) (n2=0.43, p<0.001), and the V-cut test (n2=0.24, p=0.004). A significant (p<0.05) greater performance was found at all time-points (i.e., time effect) in 10-m (n2=0.56, p<0.001), CSR (n2=0.74, p<0.001), CSL (n2=0.52, p<0.001), and V-cut (n2=0.57, p<0.001). A significant greater performance (p<0.005) was found in both groups at different time-points (i.e., group x time interaction) in 10-m, CSR, CSL, and V-cut, while NDR and NDR only reported significance (p<0.05) in group A. Specifically, post-hoc comparisons showed significant differences (p<0.05) between time point 1 and 2, and between time point 1 and 3 in all variables except for NDL (1 v 3) in group A. Group B achieved significant differences (p<0.05) between time points 1 and 3, and 2 and 3 in 10-m (p= 0.010 and 0.009), CSR (p<0.001), CSL (p= 0.002 and 0.010), and V-cut (p<0.001).
Table1: If I’m reading correctly, in NDR and NDL the mean differences between seated and standing is less than 1 mm, considering the units (cm). I’m curious about the instrument authors have used to measure navicular drop…
Answer to reviewer: A Vernier TM height caliper (Mitutoyo American Corporation, Mitotoyo, Japan) was used to calculate the navicular drop. The main scale of this simulator is graduated in centimeter, that is divided in tenths (millimeter). The vernier divide the millimeter in fifty (1/50), marking the 0.02mm (two hundredths of a millimeter)
Line 215–216: considering what comes next, the sentence “Previous studies (9,14,16,22,24,26) have found various adaptations (ES= -0.07 to 1.79) related to multidirectional ability” appears incomplete.
Answer to reviewer: Thank you for your comment. We have amended it accordingly.
Changes made in the manuscript:
“…Previous studies (9,14,16,22,24,26) have found COD and linear sprinting improvements (ES= -0.07 to 1.79) after using different training methods…”
Discuss the crossover effect and the washout implications in your results and the expected or unexpected differences between your groups A and B.
Answer to reviewer: Thank you for your consideration. We amend the limitations information, so that it now reads:“Lastly, the absence of washout time between interventions period, it is reasonable to hypothesise that the initial intervention may have influenced the group that subsequently served as the control”
Line 264: revise the “who”.
Answer to reviewer: Thank you for your comment. We have modified it accordingly.
Changes made in the manuscript:
“…This would also be favored during the squat performance if the foot accelerates until it is supported on the forefoot or if it is jumped, as occurs in Loturco et al. (2022) (16), which also improves the ability to change direction but do not measure the decrease in the navicular drop…”
References 19 and 20 are repeated.
Answer to reviewer: Thank you for your comment. We have deleted one of them.
Comments on the Quality of English Language
There are some grammatical errors in the text. I provide some examples for improvement but authors should check the text with a native with academic/scientific experience.
Answer to reviewer: Thank you for your comment. The manuscript has been checked by a native speaker.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authors1. Overall, this paper is very interesting, but I have a minor issue with readability. Although the text is scientifically well written, it was sometimes difficult to read, especially the results. Can you briefly explain the terms time effect, group effect, group x time interaction, and time x group interaction?
2. Table 1 - Are the numerical data in brackets Cohen´s d values? Can you indicate what they represent in the notes under the table?
3. Participants - You presented exclusion criteria, but was there any subject excluded from the study based on the criteria?
4. Training intervention - Can you specify the intervention in more detail? (e.g. position of the elastic band, resistance of the band -medium, high, rest interval)
Author Response
Point-by-point response to the comments of the reviewers
Paper Title: Effects of Sidestep Exercise with Elastic Bands Training on Multidirectional Speed Abilities and Navicular-Drop in Young Male Football Players
We appreciate the helpful comments of Reviewers. In order to clarify how we have responded to the reviewer, we have cut-and-pasted each comment below, responded to the comment and then explained how the comment has been accommodated in the revised manuscript. The changes in the revised manuscript are indicated in red font and English changes are provided in yellow. Where the comment raised by the Reviewer could not been accommodated within the revised manuscript, we have endeavoured to clearly explain why we did not incorporate his/her suggestions.
Reviewer #3:
Comments and Suggestions for Authors
- Overall, this paper is very interesting, but I have a minor issue with readability. Although the text is scientifically well written, it was sometimes difficult to read, especially the results. Can you briefly explain the terms time effect, group effect, group x time interaction, and time x group interaction?
Answer to reviewer: Thank you for your comment. We have briefly explained such terms within the text.
Changes made in the manuscript:
A significantly (p<0.05) greater performance was found in both groups (i.e., group effect) in NDR (n2=0.41, p=0.001), curve sprinting to the right (CSR) (n2=0.12, p=0.049) and to the left (CSL) (n2=0.43, p<0.001), and the V-cut test (n2=0.24, p=0.004). A significant (p<0.05) greater performance was found at all time-points (i.e., time effect) in 10-m (n2=0.56, p<0.001), CSR (n2=0.74, p<0.001), CSL (n2=0.52, p<0.001), and V-cut (n2=0.57, p<0.001). A significant greater performance (p<0.005) was found in both groups at different time-points (i.e., group x time interaction) in 10-m, CSR, CSL, and V-cut, while NDR and NDR only reported significance (p<0.05) in group A. Specifically, post-hoc comparisons showed significant differences (p<0.05) between time point 1 and 2, and between time point 1 and 3 in all variables except for NDL (1 v 3) in group A. Group B achieved significant differences (p<0.05) between time points 1 and 3, and 2 and 3 in 10-m (p= 0.010 and 0.009), CSR (p<0.001), CSL (p= 0.002 and 0.010), and V-cut (p<0.001).
A significant between-group difference (p<0.05) (i.e., time x group interaction) was reported at time-point 1 in NDR (n2=0.14), CSR (n2=0.13), CSL (n2=0.43), and V-cut (n2=0.24) in favor of group B, with the exception of NDR. As such, NDR showed a significant difference at time-point 2 (p<0.001, n2=0.35) in favour of group A. On the other hand, group B showed a significant better performance in CSR (p<0.013, n2=0.19), CSL (p<0.047, n2=0.13), and V-cut (p<0.001, n2=0.46) at time-point 3.
- Table 1 - Are the numerical data in brackets Cohen´s d values? Can you indicate what they represent in the notes under the table?
Answer to reviewer: Thank you for your comment. We have amended it accordingly. You can see means and SD in brackets.
Changes made in the manuscript:
Table 1. Within- and between-group comparison after the 3-week lateral step with elastic bands intervention. Values represent mean (SD).
- Participants - You presented exclusion criteria, but was there any subject excluded from the study based on the criteria?
Answer to reviewer: Thank you for your comment. No subject was excluded based on the criteria. The figure 1 shows a flow diagram related to that.
- Training intervention - Can you specify the intervention in more detail? (e.g. position of the elastic band, resistance of the band -medium, high, rest interval)
Answer to reviewer: Thank you for your comment. We have amended it accordingly.
Changes made in the manuscript:
The first three weeks, the group A performed 3 sets of 6 repetitions per side with 2 min between sets interval in the lateral-step exercise with an elastic band (Sanctband, Super Loop Purple; 4.76mm thick x 25.4mm wide x 1000mm long; 13.61KGF; Sanct Japan Co., Ltd.) attached to the waist with a belt and in a low vector anchored to the floor (see Figure 2).
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsMy major concerns have been properly amended. Nevertheless, the section Practical Applications is overly enthusiastic given your study limitations, particularly when stating that the exercise can minimize the injury risk. You have not examined effects of the resisted lateral-step exercise on injury risk, only on physical performance. Please reword.
Also, can you add the details about the caliper measurements you gave to me in the text? I.e., "the main scale of this simulator is graduated in centimeter, that is divided in tenths (millimeter). The vernier divide the millimeter in fifty (1/50), marking the 0.02mm (two hundredths of a millimeter)". Readers will be better prepared to interpret the results. In doing so, please reword in line with the explanations already provided in subsection "2.3.2. Navicular Drop Test".
Comments on the Quality of English Language(Lines 286–288) "This would also be favored during the squat performance if the foot accelerates until it is supported on the forefoot or if it is jumped, as occurs in Loturco et al. (2022) (17), which also improves the ability to change direction but do not measure the decrease in the navicular drop": I'm having difficulties in understanding the parts of the sentence highlighted in bold, particularly the latter. Is "also improves the ability to change direction but do not measure the decrease in the navicular drop" referring to the findings of Loturco et al.'s study? Can you improve (simplify) this sentence?
Author Response
Point-by-point response to the comments of the reviewers
Paper Title: Effects of Sidestep Exercise with Elastic Bands Training on Multidirectional Speed Abilities and Navicular-Drop in Young Male Football Players
We appreciate the helpful comments of Reviewers. In order to clarify how we have responded to the reviewer, we have cut-and-pasted each comment below, responded to the comment and then explained how the comment has been accommodated in the revised manuscript. The changes in the revised manuscript are indicated in red font and English changes are provided in yellow. Where the comment raised by the Reviewer could not been accommodated within the revised manuscript, we have endeavoured to clearly explain why we did not incorporate his/her suggestions.
Reviewer #3:
Comments and Suggestions for Authors
1. My major concerns have been properly amended. Nevertheless, the section Practical Applications is overly enthusiastic given your study limitations, particularly when stating that the exercise can minimize the injury risk. You have not examined effects of the resisted lateral-step exercise on injury risk, only on physical performance. Please reword.
Answer to reviewer: Thank you for your comment. We have amended it accordingly.
Changes made in the manuscript:
“The current results provide a fascinating overview that includes an easily implemented exercise within practice routines to prepare your players for training and to improve multidirectional abilities. All clubs can access such material to improve the quality of activations, increase the feedforward mechanism on any pitch with the specific football shoes used during games and training.”
2. Also, can you add the details about the caliper measurements you gave to me in the text? I.e., "the main scale of this simulator is graduated in centimeter, that is divided in tenths (millimeter). The vernier divide the millimeter in fifty (1/50), marking the 0.02mm (two hundredths of a millimeter)". Readers will be better prepared to interpret the results. In doing so, please reword in line with the explanations already provided in subsection "2.3.2. Navicular Drop Test".
Answer to reviewer: Thank you for your comment. We have amended it accordingly.
Changes made in the manuscript:
“A Vernier TM height caliper (Mitutoyo American Corporation, Mitotoyo, Japan) was used to calculate the navicular drop; the main scale of this simulator is graduated in centimeter, that is divided in tenths (millimeter). The vernier divide the millimeter in fifty (1/50), marking the 0.02mm (two hundredths of a millimeter).”
Comments on the Quality of English Language
3. (Lines 286–288) "This would also be favored during the squat performance if the foot accelerates until it is supported on the forefoot or if it is jumped, as occurs in Loturco et al. (2022) (17), which also improves the ability to change direction but do not measure the decrease in the navicular drop": I'm having difficulties in understanding the parts of the sentence highlighted in bold, particularly the latter. Is "also improves the ability to change direction but do not measure the decrease in the navicular drop" referring to the findings of Loturco et al.'s study? Can you improve (simplify) this sentence?
Answer to reviewer: Thank you for your comment. We have amended it accordingly.
Changes made in the manuscript:
“The lateral-step favors that in the deceleration-acceleration phase of the movement, all the foot pressure falls on the median arch of the foot and the longitudinal line that joins the first toe with the heel. This would also be favored during the squat performance if the foot accelerates until it is supported on the forefoot or if it is jumped (17).”
Author Response File: Author Response.pdf
