Regular Intermittent Aerobic Exercise Reduces Arterial Stiffness Associated with Postprandial Hyperglycemia in Middle-Aged and Older Individuals

Round 1

Reviewer 1 Report

The authors investigated the effect of an intermittent aerobic training programme on the kinetics of arterial stiffness markers after an OGTT in middle aged healthy participants. The rationale of the study is valid and novel and is presented clearly in the introductory section. The main shortcoming of the study is the lack of nutritional and biochemical data which could better explain the effect of exercise on hyperglycemia induced arterial stiffening.    

Major comments

1. Methodology: The authors should describe the randomization process.

2. Methodology: A major shortcoming of the work is the lack of nutritional and physical activity information for the participants. If these data exist the authors should present them in the results section. Otherwise they should mention this as a limitation of the study

3. Methodology: The effect of Time, Time x group and Group should be clearly presented in the tables and figures by the respective p values.

4. Table 1. Is it correct that the Pgroup value of VO2max is higher than 0.05 ? It seems strange since there is an increase of VO2max in the IAT group while it remains stable in the CON group

5. A correlation analysis of iAUC of glucose and baPWV either in the whole sample or separately in the different groups may provide information on whether the magnitude of postprandial hyperglycemia correlates with the increase of baPWV

6. It seems that hyperglycemia significantly improved from 0 to 4 weeks and remained stable till 8 weeks while there is a continuous improvement of baPWV in the IAT group. Could the authors comment on this ?

It is recommended that you should correct minor syntactical errors with the help of a native English speaker

Author Response

Responses to Reviewer 1

We appreciate your attention to our manuscript. We feel that our submission has been considerably enhanced by implementing your valuable advice. We addressed the specific comments as outlined in detail below, and modifications to the revised text are highlighted in red. We hope you will agree that the changes have rendered our report acceptable for publication.

Methodology: The authors should describe the randomization process.

Response

Page 2-

Line 80

We have described.

Methodology: A major shortcoming of the work is the lack of nutritional and physical activity information for the participants. If these data exist the authors should present them in the results section. Otherwise, they should mention this as a limitation of the study

Response

Page 10-

Line 377

We mentioned as a limitation of our study.

Methodology: The effect of Time, Time x group and Group should be clearly presented in the tables and figures by the respective p values.

Response

Page 5-

Line 196-

We have appended as much as we can.

Table 1. Is it correct that the Pgroup value of VO2max is higher than 0.05 ? It seems strange since there is an increase of VO2max in the IAT group while it remains stable in the CON group

Response

Page 5-

Line 190

VO₂max p-value was less than 0.05. We have revised the table.

A correlation analysis of iAUC of glucose and baPWV either in the whole sample or separately in the different groups may provide information on whether the magnitude of postprandial hyperglycemia correlates with the increase of baPWV

Response

No correlation was found between blood glucose and baPWV after 75g OGTT. Therefore, we concluded that this was not an important result in this case.

It seems that hyperglycemia significantly improved from 0 to 4 weeks and remained stable till 8 weeks while there is a continuous improvement of baPWV in the IAT group. Could the authors comment on this ?

Response

Page 9

Line 351-

We have added to the discussion.

Reviewer 2 Report

Although it is already a known fact that exercise prevents atherosclerosis, the present article discusses the effects of intermittent exercise.　Conguratuathions.

 The characters of the subjects are relatively healthy middle-aged people, it is necessary to examine a wide range of patients if the effects of intermittent exercise are to be accurately described.　

Additionally, the number of subjects is too small (30). The weight change during 8 weeks in the patient group should also be shown in the graph.

Also, how do the changes in dietary balance, etc. in the intervention group compare to the control group?　It seems to me that there is an intervention bias.

Without a comparison with the continuous exercise group, the effectiveness of intermittent exercise cannot be proven.　

Author Response

Responses to Reviewer 2

We appreciate your attention to our manuscript. We feel that our submission has been considerably enhanced by implementing your valuable advice. We addressed the specific comments as outlined in detail below, and modifications to the revised text are highlighted in red. We hope you will agree that the changes have rendered our report acceptable for publication.

Although it is already a known fact that exercise prevents atherosclerosis, the present article discusses the effects of intermittent exercise. Conguratuathions.

The characters of the subjects are relatively healthy middle-aged people, it is necessary to examine a wide range of patients if the effects of intermittent exercise are to be accurately described.

Response

Page 10

Line 377-

We have appended to the limits of our study.

Additionally, the number of subjects is too small (30). The weight change during 8 weeks in the patient group should also be shown in the graph.

Response

Page 10

Line 377-

We have added to the study limitations that we have few subjects.

Page 5

Line 194-

We have also included a figure showing the change in body weight.

Also, how do the changes in dietary balance, etc. in the intervention group compare to the control group?　It seems to me that there is an intervention bias.

Response

Page 2

Line 58-

We included subjects who had no abnormalities in their nutritional intake prior to the study.

Without a comparison with the continuous exercise group, the effectiveness of intermittent exercise cannot be proven.

Response

Page 2

Line 58-

We add that we did not compare intermittent and continuous aerobic exercise to the limitations of our study.

Reviewer 3 Report

Kobayashi and Neguro investigate the effects of moderate aerobic exercise on arterial stiffness after glucose consumption. The authors find that after 4-8-week exercise PWV does not increase after glucose intake. 

The manuscript lacks the explanation of rationale of the study, e.g. why is PWV or arterial stiffness increase after glucose intake. This is not clearly communicated in the text. Is this increase observed in older individuals or also the young healthy individuals? PWV seem to decrease with normalization of the glucose levels. Why? It seems that the only the baPVS decrease after exercise and not the cfpPWV. How do authors explain this? How do you think exercise reduces acute increase in PWV after glucose intake? It seems that he 4-8-week exercise did not decrease PWV independent of glucose intake. What could be the explanation?

English text must be significantly improved.

Author Response

Responses to Reviewer 3

We appreciate your attention to our manuscript. We feel that our submission has been considerably enhanced by implementing your valuable advice. We addressed the specific comments as outlined in detail below, and modifications to the revised text are highlighted in red. We hope you will agree that the changes have rendered our report acceptable for publication.

Kobayashi and Neguro investigate the effects of moderate aerobic exercise on arterial stiffness after glucose consumption. The authors find that after 4-8-week exercise PWV does not increase after glucose intake.

The manuscript lacks the explanation of rationale of the study, e.g. why is PWV or arterial stiffness increase after glucose intake. This is not clearly communicated in the text. Is this increase observed in older individuals or also the young healthy individuals? PWV seem to decrease with normalization of the glucose levels. Why? It seems that the only the baPVS decrease after exercise and not the cfpPWV. How do authors explain this? How do you think exercise reduces acute increase in PWV after glucose intake? It seems that he 4-8-week exercise did not decrease PWV independent of glucose intake. What could be the explanation?

Response

Page 9

Line 351-

I added the difference in arterial stiffness changes after glucose ingestion in younger and older adults or between cfPWV and baPWV.

In addition, blood pressure was added as a reason for the change in arterial stiffness after glucose intake.

Round 2

Reviewer 1 Report

The authors responded adequately to my comments and improved the scientific quality of the manuscript 

Minor editing of English language required

Reviewer 2 Report

Agree to Publish