Reviewer ’s report  
 
Title: Effects of prolonged exercise versus multiple short exercise sessions on risk for metabolic  
syndrome and atherogenic index in middle -aged obes e women: A randomised controlled trial  
 
Version: 0 Date: 21 Jun 2016  
 
Reviewer: Rebecca Hasson  
 
Reviewer's report:  
 
The article entitled: "Effects of prolonged exercise versus multiple short exercise sessions on risk 
for metabolic syndrome and atherogenic index in middle -aged obese women: a randomised 
controlled trial" aimed to investigate the effect of exercise duratio n on cardiometabolic outcomes 
in a group of sedentary obese women. The major findings of this study indicate that prolonged 
exercise is superior to multiple short sessions for lowering the risk of metabolic syndrome risk 
and the AI in middle -aged obese wom en. This manuscript is well written and used 
comprehensive study design, however the conclusions drawn regarding the effects of exercise on 
these outcomes without a discussion of the imposed energy deficit and/or discussion regarding 
the dietary intake dat a dampens my enthusiasm for the publication of this manuscript in its 
present form. In addition, this study appears to be a weight loss study and not an exercise study 
and should be framed as such. My major and minor comments are mentioned below:  
 
 
 
 
MAJOR CO MMENTS:  
 
1. The caloric restriction portion of the study is unclear. Were all of the groups (including 
the control group) instructed to restrict their caloric intake by 300kcals? Moreover, did 
the 200 kcal energy expenditure from exercise result in a 500 kc al deficit in the 
exercising groups? What was the purpose of the caloric restriction? This is a confounding 
variable in determining which duration of exercise is more beneficial for cardiometabolic 
outcomes. Again, this appears to be a weight loss study no t a study about different 
exercise durations. More detail is needed regarding this energy deficit and its potential 
confounding effects on study results.  
 
 
 
2. As a follow -up to the first point, since the authors have dietary data for the participants 
this i nformation should be included in the manuscript. What was the average total daily 
energy intake for the participants? The authors should also estimate the total daily energy 
expenditure to get some understanding of energy balance in this cohort.  
 
 
 
3. As a follow -up to the first point, for the SSG group, it is unclear whether the 
improvements in risk factors for metabolic syndrome and AI are a function of a different 
duration/same dose of exercise rather than the effects of weight loss. Statistical analyses 
should be completed to assess the effects of SSG on these parameters controlling for 
changes in weight.  
 
 
 
4. ACSM recommendations are to exercise "most days of the week " which is typically 
interpreted as 5 days a week, expending approximately 1500kcals per  week. This is 
incorrectly stated in the first paragraph of the Discussion and should be revised for 
accuracy.  
 
 
 
5. A limitation section should be included in this manuscript.  
 
 
MINOR COMMENTS:  
 
1. Page 5, the authors state "the results confirmed 36 to be a sufficiently large sample size 
for statistical interference". Much more detail is needed regarding whether or not the 
remaining sample size is sufficient to make statistical inferences.  
 
 
 
2. Results should be rewritten to not only state significant diffe rences but the direction of 
the differences to help the reader better understand the group and intervention results.  
 
 
 
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
Yes 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
 
No 
Are you able to assess any statistics in the manuscript o r would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, please specify what aspects require further  
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written Englis h 
Please indicate the quality of language in the manuscript:  
 
Acceptable  
 
 
 
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, fees, funding,  or salary from an  
organisation that may in any way gain or lose financially from the publication of this  
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose  
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents relating to the content of the  
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing interests in relation to this paper?  
 
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below.  If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests  
 
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