Title: Isometric and isokinetic strength of lower-limb muscles in female athletes during different
phases of menstrual cycle: a causal- comparative study.
Version: 1 Date: 05 Aug 2023
Reviewer:  Vedran Hadži#
Reviewer's report:
Dear authors,
I think that you have chosen an interesting research topic. For my taste the introduction part is
too long, but this can be corrected. I was most disappointed with the way the strength testing
was described, as isokinetic strength testing is my primary area of expertise. You can not report
the methods so vaguely. Your division of cycle into phases is limited as there were no hormone
tests included, and to top it all, you don't even mention that as limitation (there is no limitation
paragraph at all!). In the discussion section, apart from the first paragraph, you are discussing
the findings of other studies and not your own. This are the reasons I am proposing rejection of
your paper. For more detailed comments, please see below.
Line 111: Given the study repeated measured ANOVA (1 group and three repeated measures),
a medium overall effect size f=0.25, an #-error=0.05, and a desired power (1-ß error) = 0.8, the
total sample size resulted in thirty-five participants.
Please revise the sentence as you are probably referring to study design. Additionally, when you
input your parameters into G*power you get 28, not 35 participants?
Line 116: do you have information about the number of trainings per week, as this is more
relevant than years of training.
Line 124: disruption in the menstrual cycle - what did this include? was it explained to the
participants?
Line 139: what is statistical population?
Line 146-148: you did not use any more precise method to define cycle phases? Why not? This
is the major limitation of this study, that probably cannot be accounted for.
Line 148: It Biodex System 4 PRO probably?
Line 151: The student performed a 15-minute warm up on a cycle ergometer at desired speed
at each session.  What does this mean - at desired speed? It is necessary to set load in Watts
and require a certain revolution from a participant, not the speed. Also this whole paragraph is
repeated twice, please go through your submission PDF more carefully.
Lines 170-175: For isokinetic test you must state which type of contraction was actually used.
It seems that you have tested Q in concentric, and H in eccentric mode of contraction. The rest
period of 20 seconds  is stated but it is not clear to what is this relates to. How many sets with
how many repetitions did you perform? Knowing Biodex System 4 PRO, it is impossible to test
both muscles (Q and H) in different contraction modes within single set. Please make it clear in
the methods: number of sets and repetitions with contraction modes at give velocity..
Lines 177-180: Was a 20 seconds pause given between different muscle groups? Also at which
angle did you perform the test as this is crucial for understanding the results.
Line 183: data were normalized using the Shapiro–Wilk test - this test is used to check normality
of the data, not to normalize data.
Line 200: you are using absolute strength not the realtive one, explain why. Unit is Newto-meter
(Nm) not N.m2 . Did you calculate power or strength ratio? Is this HQR ratio of DFR (dynamic
functional ratio where Hecc is divided by Qconc strength)?
Line 226: what does the thumb abductor muscle strength has to do with Q and H strength?
Discussion has deal a little with your results and the only relevant paragraph is the first one.
You must stick to your results, while you are discussing findings of other studies instead of
yours. You did not have any hormone levels so you can’t actually confirm that changes you
have observed are related to cycle itself or are just occuring as daily variations. Also, there is
no limitations section at all.