Metabolically Guided Walking and Plant-Based Nutrition Enhance Body Composition and Weight Loss

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This is an interesting manuscript that examined the impact of varying intensities of fuel exchange through a walking-based PA intervention on metabolic efficiency and body composition in sedentary middle-aged overweight / obese women. The authors found that the body fat composition demonstrated significant reductions across all participants but the moderate-intensity group demonstrating more favorable results. However, there are some points should be addressed in this manuscript:

1. Are there any differences on the baseline anthropometric and body composition characteristics?
2. It would be more appropriate to use the percentage of change on body composition parameters.
3. As figures 1to 4 could be merged in Table 2.
4. Also for the Table 3, please demonstrate the percentage change on resting metabolism parameters.
5. For Table 3, the statistical testing adjusted for BMI or body fat?
6. As figures 6 to 9 which could be deleted or modified as one figure.

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This manuscript addresses an important issue within public health and exercise science. However, in its current form, the study requires minor revisions:

Introduction - Please streamline and make the motivation for this study more explicit. It is too lengthy, with overlapping explanations. Focus on the study rationale and hypotheses.

Methods – The description of participant selection and inclusion/exclusion criteria is limited and lacks clarity.  Describe how randomization was implemented. 
Provide more detail on adherence to the diet and exercise protocols.
Explain handling of dropouts/missing data.

Discussion – The current text suggests strong superiority of moderate-intensity training; however, conclusions should be more cautious, highlighting the need for larger and longer-term trials.

Conclusion – The findings are preliminary and should not be generalized as broadly as presented. The conclusion should instead emphasize the exploratory nature of the work.

Expand this section to include the limitations:
 - Small sample size.
- Gender- and age-specific restriction (only sedentary, middle-aged women).
- Short duration (8 weeks).
- Lack of long-term follow-up on sustainability.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Manuscript Title: Respiratory Exchange Ratio–GuidedWalking and Plant-Based Nutrition Improve MetabolicEfficiency and Body Composition in Sedentary Middle-AgedOverweight/Obese Women

1. Title

The title accurately represents the study’s dual focus on RER-based exercise prescription and plant-based nutrition. However, it remains long and slightly technical. The phrase“Respiratory Exchange Ratio–Guided Walking” might not be immediately accessible to a general readership. A moreconcise alternative such as “Metabolically Guided Walkingand Plant-Based Nutrition” would preserve precision whileimproving readability.

2. Abstract

The abstract is comprehensive yet overly dense in statisticaldetail. It should conform to the standardized Background–Methods–Results–Conclusions structure.
While numerical findings are clearly reported, thephysiological and clinical implications are not sufficientlyemphasized. The conclusion could better highlight thetranslational relevance—particularly the potential integrationof RER-guided exercise and plant-based diets into obesityprevention or rehabilitation programs.

3. Introduction

The introduction demonstrates a solid understanding of obesity-related metabolic dysfunction, energy balance, and thepotential role of plant-based diets. However:

• Several paragraphs repeat the same conceptual content(e.g., homeostasis, energy expenditure). • The rationale for combining RER-guided exercise withplant-based nutrition should be presented as a distinctinnovation relative to conventional intensity prescriptions(%VO₂max, heart-rate zones). • The hypothesis should be explicitly formulated, and thepotential mechanisms—such as improved metabolicflexibility, enhanced fat oxidation, or mitochondrialefficiency—should be clearly linked to the studyobjectives.

Including a brief discussion on the limitations of priorinterventions that overlooked RER feedback would alsostrengthen the research justification.

4. Methods

The methodological framework is sound but lacks criticaltransparency on several fronts:

• Study Design: The study is described as an 8-week randomized trial, yet the randomization, allocationconcealment, and adherence monitoring processes areinsufficiently detailed. Clarifying these procedures is necessary to confirm internal validity. • Sample Size and Power: There is no reference to a prioripower analysis. Given the limited sample (n = 44), it is uncertain whether the study is adequately powered todetect meaningful between-group differences. • Dietary Composition and Control: The plant-basedintervention is mentioned but not quantified in macronutrient terms (% carbohydrate, % fat, % protein). Protein adequacy, amino-acid quality (e.g., PDCAAS orDIAAS), and micronutrient support (vitamin B₁₂, iron, calcium) should be clarified. Compliance monitoringmethods—food records, recalls, or supervision—must be specified. • Exercise Protocol: The description of progressive walkingsessions is appropriate, but it is unclear whether intensitywas individualized by direct gas-exchange assessment orestimated from calibration trials. Were heart-rate monitors used to ensure participants maintained the targetRER? Feasibility of RER-guided training in sedentarypopulations should also be discussed, consideringtechnological demands of gas analysis. • Measurement Reliability: Although BodPod and indirectcalorimetry are valid, inter-session reliability (e.g., ICC values) and calibration details are missing. • Cardiorespiratory Assessment: The method used todetermine ventilatory threshold (Bruce, Balke, or other) should be described. Reporting both absolute and relativeVO₂ (mL·kg⁻¹·min⁻¹) would improve interpretability in overweight participants. • Statistical Analysis: ANCOVA and GLM are appropriate, yet assumptions (normality, homogeneity), correctionprocedures (Bonferroni, Tukey), and effect-size interpretation are not provided. Effect magnitudes (e.g., partial η² > 0.8) should be contextualized in terms of practical or clinical significance.

 

5. Results

Results are well organized and logically presented. Reductionsin body fat, preservation of lean mass, and improvedmetabolic efficiency are convincing. However:

• Some p-values and partial η² statistics are given withoutconfidence intervals or interpretation of effect size magnitude. • Figures 1–9 contain repetitive text and could be streamlined for clarity. • Thermogenic and substrate-oxidation explanationsoccasionally overlap with the Discussion. • Dropout rates are described only qualitatively; precisenumbers and reasons for attrition should be reported, alongside clarification of whether analyses followed an intention-to-treat or per-protocol approach.

Statistical reporting should align with CONSORT and APA guidelines for transparency and reproducibility.

6. Discussion

The discussion commendably integrates physiologicalmechanisms with the main findings. The argument thatmoderate-intensity RER (~0.80) training enhances fatoxidation while preserving lean mass is coherent. Yet severalareas warrant refinement:

• The section is excessively long, with redundant data restatement. • Mechanistic explanations (e.g., “mitochondrial overload,” “metabolic stagnation”) are plausible but speculativewithout biochemical validation. More cautious languageand references to primary sources (e.g., mitochondrialbiogenesis, CPT-1 activity, insulin sensitivity) wouldimprove rigor. • Differences between moderate- and high-intensity groupsshould be interpreted in terms of adherence, perceivedexertion, and real-world feasibility, not only metabolicefficiency. • Potential confounders—baseline fitness variation, unmonitored daily activity, and small sample size—should be acknowledged. • A short “Future Directions” paragraph suggesting longer-term follow-up, inclusion of male participants, orhormonal and menopausal status analysis would enhancerelevance. • Translational implications for clinical dietetics orcommunity weight-management programs should be more explicitly discussed.

7. Overall Assessment

This study offers an innovative attempt to integrate metabolicfeedback–based exercise prescription with a plant-baseddietary pattern—an underexplored but promising approach toimproving metabolic efficiency. The results arephysiologically credible and fit well within the journal’sscope.

However, to reach publishable standard, the manuscriptrequires improved methodological transparency, strongerstatistical reporting, better linkage between RER andbiochemical outcomes, and more concise discussion. Addressing the nutritional adequacy and practical feasibilityof the intervention will substantially enhance its translationalimpact.

8. Recommendation

Major Revision

Key points requiring attention:

1. Clarify randomization, power analysis, and adherencemonitoring procedures. 2. Provide full macronutrient composition, protein quality, and diet-compliance data. 3. Detail exercise-intensity calibration and discuss RER-guided training feasibility. 4. Report reliability indices, VO₂ normalization, andstatistical assumptions. 5. Streamline figures and avoid redundancy in theDiscussion. 6. Strengthen mechanistic and translational arguments withtargeted references. 7. Expand on the public-health and clinical relevance of findings.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

Thank you for your revisions.

Author Response

Response to Reviewer #3 (R3) Comment 1: Title
Response: A new, simplified title improves accessibility and clarity.

Metabolically-Guided Walking and Plant-Based Nutrition Enhance Body Composition and Weight Loss.

Comment 2: Introduction Redundancy & Mechanistic Clarity

Response:
Removed repetitive discussion of homeostasis
Clarified the innovation of RER-guided exercise versus VO₂-based prescriptions
Added an explicit hypothesis and objective
Positioned the research model within a global public health framework