Should the Minimal Intervention Principle Be Considered When Investigating Dual-Tasking Effects on Postural Control?
Round 1
Reviewer 1 Report
The authors analyzed COP and motion tracking during du.al-tasking and performed principal component analysis using postural movement components. Anterior-posterior ankle sway, which was represented in PM1, decreased in amplitude (aVark) and was indicated as high importance of postural control.
The authors provide interesting data; however, it needs a revision.
COP analyses demonstrated the effects of dual-task on COP deviation, velocity, and amplitude. The differences among the three conditions were significant; however, the effect size of the dual-task seems to be small.
The authors need to explain why they choose counting backward for this trial.
If the authors demonstrate the regression analyses between COP parameters and aVark, it would help understand their results.
Author Response
Dear Editor, dear Reviewer,
Thank you for the opportunity to revise our manuscript and for the very constructive comments. We believe that we could address all of the stated comments and have revised our manuscript accordingly.
Please see the attachment.
Thank you for your time and your valuable advice.
On behalf of all coauthors,
sincerely,
Felix Wachholz
Author Response File: 
Author Response.pdf
Reviewer 2 Report
In the present paper, the authors suggested considering the minimal intervention principle in investigating the effect of the dual-task on postural control of neuromuscular motor control.
The authors derived the absolute variance of the movement and the frequency of adjusting motor control by conducting principal component analysis from the result of three different postural control tasks.
The experiment design is sound and clear to test the hypothesis, and an appropriate method of analysis was used.
However, it would be nice if section 2.6, 2.7, 2.8 provides a more detailed explanation illustrating the procedures to improve the reproducibility of the study. For instance, in line 155, the authors mentioned "an algorithm" to calculate the knee angle. Clarification if the algorithm is whether a conventional one that calculates a joint angle or a specific one would be helpful. Moreover, the process of deriving variables from kinematic data to the target-dependent variable (aVark, Nk) is well explained but still somewhat not clear. It would be nice if the authors provide a mathematical formula or a diagram that clearly shows the process of calculation.
Lastly, in the introduction and in the discussion, the authors suggested considering MIP to evaluate the effect of the dual-task on postural control. While the MIP may have more potential that it can be used to investigate other kinematic motor control tasks, the authors focused on the postural control and cognitive load only. Therefore, either discussing the potential and possible application of MIP or provide the reason why the authors just wanted to discuss MIP in dual-task related performance changes of postural control would be greatly appreciated.
Thank you
Utilizing MIP to assess the kinematic movement control is a noble approach
Author Response
Dear Editor, dear Reviewer,
Thank you for the opportunity to revise our manuscript and for the very constructive comments. We believe that we could address all of the stated comments and have revised our manuscript accordingly.
Please see the attachment.
Thank you for your time and your valuable advice.
On behalf of all coauthors,
sincerely,
Felix Wachholz
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The authors adequately revised their manuscript.
