The Impact of Effective Mass on the Strength of Side and Turning Kick in Taekwon-Do Male Practitioners

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The quality of the paper can be improved with the following points:

Introduction:

1. This study investigated the turning kick and side kick in ITF style. However, this message was not clearly delivered in introduction part which might mislead the audiences reading the information in this article from WT perspective. There are some differences between the biomechanics of these two kickings in the ITF and WT styles which should be clearly mentioned in the introduction part. 

2. Lots of studies have already investigated the biomechanics of turning kick (roundhouse kick) and side kick in taekwondo. Hence, what would be the significance of this study if the research questions have already been answered by other researchers?

3. Why is it important to compare the effective mass of turning kick and side kick? Due to the high prevalence of these two kickings in the competition? Any academic basis from previous studies? 

4. The authors should provide more literatures in supporting the significance of conducting this study.

Methods:

1. The sample size is too small. Authors may consider to list out the inclusion criteria in details so that the small sample size can be justified. 

2. Athletes tend to generate greater force by the dominant leg but authors didn't record it in the method part (or haven't reported it).

3. Only foot acceleration was investigated in this study which provided very little information about the biomechanics of kicking. Authors may consider to take the angular movement of the joints during kicking into considerations for conducting the analysis. 

Results:

1. The dominant leg of athletes may affect the force generated of kickings which should be reported in the results part.

Discussion:

1. Fairly written. It is suggested to add more previous literatures in order to provide a thorough discussion on this topic. 

 

 

Comments on the Quality of English Language

Nil 

Author Response

Dear Reviewer,

Thank you for your kindness and effort in pointing out flaws in our paper. We would like to thank you for your comments and address each of them separately by answering one by one:

Introduction:

1. This study investigated the turning kick and side kick in ITF style. However, this message was not clearly delivered in introduction part which might mislead the audiences reading the information in this article from WT perspective. There are some differences between the biomechanics of these two kickings in the ITF and WT styles which should be clearly mentioned in the introduction part. 

#You are correct. We added explanations in bracets in introduction section and abstract as well, so we will not misguide any potential readers even at the point of article search and selection.

2. Lots of studies have already investigated the biomechanics of turning kick (roundhouse kick) and side kick in taekwondo. Hence, what would be the significance of this study if the research questions have already been answered by other researchers?

# We agree you can find many positions describing the biomechanics of these kicks. However, we focused on a phenomenon rarely described in the available literature, i.e. determination of effective mass. In addition, we present a method of determining it, which is not found in the literature.

3. Why is it important to compare the effective mass of turning kick and side kick? Due to the high prevalence of these two kickings in the competition? Any academic basis from previous studies? 

# The essence of our measurement is not to compare the two kicks, but to determine the effective weight for the two most commonly used kicks in ITF taekwon-do and its contribution to strength. Our research shows that greater force is associated with the contribution of greater effective mass. This may be related to movement technique and to the way the strike is executed

4. The authors should provide more literatures in supporting the significance of conducting this study.

#A more thorough description has been provided. We have increased the references in the text to 43 literature items that meet the standards of an experimental study. We used the most flagship article on this topic in reference 26.

Methods:

1. The sample size is too small. Authors may consider to list out the inclusion criteria in details so that the small sample size can be justified. 

# Information on the calculated minimum measurement positions and test power is provided

2. Athletes tend to generate greater force by the dominant leg but authors didn't record it in the method part (or haven't reported it).

# We agree with the reviewer in this regard. However, our study did not show statistical significance in kicking strength between the left and right legs. There are studies that confirm this specificity in ITF taekwon-do athletes.

3. Only foot acceleration was investigated in this study which provided very little information about the biomechanics of kicking. Authors may consider to take the angular movement of the joints during kicking into considerations for conducting the analysis. 

# We decided to focus solely on measuring acceleration and force to determine effective mass. We did not find such an approach to this problem in the available literature. We think that this is a method that has not been used before, which requires the appropriate apparatus that we have. We deliberately do not give other parameters to better build our message. Thank you for this suggestion we will certainly take it up in future works.

Results:

1. The dominant leg of athletes may affect the force generated of kickings which should be reported in the results part.

# Our study did not show statistical significance in kicking strength between the left and right legs

Discussion:

1. Fairly written. It is suggested to add more previous literatures in order to provide a thorough discussion on this topic. 

#We extended following part of text with explanation, why going through all literature that exist upon topic will not reflect our results:

Study by Thibordeeand and Prasartwuth [34]  had even lower values up to 200 N. A study of side kick by Jung-Hyun et al. [35] also got lower values around 1300 N. Differences in study designs can be attributed to various factors, such as the chosen targets, their size, the distance of participants from these targets, and the height of the targets. These elements must be considered when comparing force values across different studies. The challenges in reproducing these studies arise from the variability in technique execution, the non-standardization of distances, and the heterogeneous nature of the equipment, like shields or dummies in some of mentioned studies. As the study of the subject is more or less 15 years old with current setup capabilities, our study have fixed column that did not move. It might be a reason why we got higher values of force comparing to other studies, considering lack of force loss upon impact.

Reviewer 2 Report

Comments and Suggestions for Authors

I think this article very well reaches the standards asked from MDPI publishing with a good introduction on the topic at hand only thing missing might be a little reference to similar studies on the same discipline or in case that they are none a mention if it. The methods are scientifically sound and conclusions are relevant.

Author Response

Dear Reviewer

We would like to thank you for your positive feedback on our work and comments that enriched our work. According to your suggestion, we have made changes. 
We added some references with explanation why there is no exact similarity in those studies that allows our results to be comparable.

Reviewer 3 Report

Comments and Suggestions for Authors

My recommendations are the following:

Abstract - the introduction of a background phrase on the topic of the study.

Statistical analysis - I recommend that you also enter the arithmetic mean and standard deviation parameters used in the presentation of anthropometric data.

Lines 140-141 - for this aspect it is not necessary to mention the bibliographic index 7, I recommend its deletion, only the location is presented.

I recommend that in table 1, the arithmetic mean and standard deviation should be mentioned in a separate column or in parentheses.

I recommend that under table 1 the reference threshold of p.

The article has logic and is well organized and presented. But, only 4 subjects, I think they are very few, in this sport that has many participants. In this sense, I recommend mentioning the strength of the sample.

Also, a determination of the targeted specific indices was made, without any intervention. It was more interesting if an evolution of the parameters was aimed at a certain unit of time.

Author Response

Dear Reviewer

We would like to thank you for your positive feedback on our work and comments that enriched our work. According to your suggestion, we have made changes (below):

 

Abstract - the introduction of a background phrase on the topic of the study.

# Relevant phrases added

Statistical analysis - I recommend that you also enter the arithmetic mean and standard deviation parameters used in the presentation of anthropometric data.

# Supplemented as recommended

Lines 140-141 - for this aspect it is not necessary to mention the bibliographic index 7, I recommend its deletion, only the location is presented.

# As suggested, the reference in this sentence has been removed

I recommend that in table 1, the arithmetic mean and standard deviation should be mentioned in a separate column or in parentheses.

# Supplemented as recommended

I recommend that under table 1 the reference threshold of p.

# Supplemented as recommended

The article has logic and is well organized and presented. But, only 4 subjects, I think they are very few, in this sport that has many participants. In this sense, I recommend mentioning the strength of the sample.

# Information on the calculated minimum measurement positions and test power is provided

Also, a determination of the targeted specific indices was made, without any intervention. It was more interesting if an evolution of the parameters was aimed at a certain unit of time.

# The main purpose of the study was to determine effective mass and evaluate its effect on kicking power. In this study, we did not deal with changes in indicators over time, but this is an inspiring suggestion.

Reviewer 4 Report

Comments and Suggestions for Authors

I am happy with the study. It is well presented and referenced. However, results must be more clearly compared to other studies, and contribution to that extent must be more clear. The authors must also explain why results are different. Is the samle of athletes different in terms of age, ethnicity, training, body shape, gender, height, body weight? These have to be communicated on the conclusion and in the introduction as well.

Comments on the Quality of English Language

-

Author Response

Dear Reviewer

Thank you very much for appreciating our article. In accordance with your suggestion, we have added elaboration in both the introduction and discussion emphasize the innovation of our research and supported this with additional references. The study group was homogeneous in terms of age, ethnicity, training, body shape, gender, etc.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

No further comments for the revised version.