Cardiovascular Responses to a Full Resistance Training Session Performed with and Without Blood Flow Restriction

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Please use the following as what they are intended, suggestions and/or comments-observations meant to assist in the final refinement of the manuscript. I found this product well-organized and soundly presented. The following are an attempt to help. 

"This component is primarily responsible for triggering neuromuscular reflexes, particularly the mechanoreflex and the metaboreflex, which in turn contribute to the activation of the sympathetic branch of the autonomic nervous system." This is a good explanation, but it could be more direct. Consider rephrasing for better flow.

 The argument about the lack of research on full-body sessions is a key justification for the study. It's well-stated, but it could be more prominent.

 The cuff pressure is set at "50% of resting SBP." This is a critical detail. Was this pressure maintained throughout the sets or only during the exercises? Did the pressure change as SBP increased during the session? Also, were the cuffs applied to both the arms and thighs simultaneously? The description could be more specific regarding cuff application and pressure management during the full session.

The statistical analysis section is quite detailed. While useful, some of the specific statistical tests and effect size interpretations could be moved to a supplementary materials section to streamline the main text.

Table 1: The table is difficult to read due to formatting issues. The columns for "RE_HL" and "RE_LL+BFR" seem to be combined. It's also missing the "DBP" data for the "RE_HL" group and has a formatting error with the p-value for SBP. The table should be corrected to clearly present all the data points, including means, standard deviations, and p-values for both groups and time points.

The text mentions that DBP showed a "slight elevation in both conditions," but the bar charts in Figure 1 do not include DBP. This variable is also missing from the abstract. Consider adding a fourth panel for DBP to Figure 1 or explaining why it was omitted.

The discussion states that high-intensity RE is "largely attributed to increased motor unit recruitment, the magnitude of the static component, and stimulation of muscular mechanoreceptors." It would be beneficial to explain how the static component plays a role in this context for readers who may not be experts in exercise physiology.

The discussion of metabolic mechanisms and lactate accumulation is good, but it would be stronger if it included specific data points or reference to a previous study that quantified these effects to support the claims.

The limitations are well-stated. The manual measurement of blood pressure is a valid limitation, as it introduces potential error. Suggesting a future study with continuous monitoring methods (e.g., intra-arterial catheter or a continuous non-invasive device) would strengthen the manuscript.

The conclusion about BFR eliciting "hemodynamic responses comparable to traditional high-load training, but with reduced cardiovascular strain" seems to contradict the results.

Author Response

We thank you for taking the time to review this manuscript and for providing comments that have substantively enriched the work. Please find the responses to your comments on the file attached.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

I found this manuscript to be timely and relevant, particularly given the growing interest in blood flow restriction (BFR) training among both clinical and athletic populations. The study addresses a clear gap in the literature by comparing hemodynamic responses to full-body resistance exercise (RE) sessions using high loads versus low loads combined with BFR. The inclusion of multiple exercises involving both upper and lower body muscle groups reflects a more ecologically valid training setting than what is typically reported in the literature. The manuscript is generally well-structured, methodologically sound, and offers practical implications for populations with cardiovascular vulnerabilities. That said, several aspects require clarification or revision before the study can be considered for publication.

Major Comments

1. Measurement Methodology and Standardization

One of my main concerns lies in the manual measurement of systolic blood pressure (SBP). The authors do not specify critical details such as the measurement arm, body position, or the qualifications of the evaluator. In studies of acute cardiovascular responses, continuous or automated methods are typically preferred due to their consistency and reduced potential for observer bias. The potential variability introduced by manual measurement is significant and should be more directly acknowledged in both the methods and limitations sections.

2. Limited Generalizability of the Sample

The sample consists entirely of young, trained males, which severely limits the generalizability of the findings. Despite this, the discussion repeatedly draws implications for clinical populations, including hypertensive and cardiac patients. While I understand the relevance of these comparisons, it is essential that the authors more clearly distinguish between actual data and speculative extrapolation. Statements suggesting clinical safety based on this healthy cohort should be rephrased with greater caution.

3. Absence of Perceived Exertion or Discomfort Measures

Given the known discomfort associated with BFR protocols, I was surprised that no ratings of perceived exertion (RPE) or local discomfort were collected. These measures would have provided valuable insight into the subjective experience of the participants and the tolerability of the protocol. The absence of such data weakens the practical interpretation of the findings, especially in terms of feasibility and compliance in real-world training or clinical settings.

4. Misleading Use of “Respiratory Responses” in Title and Abstract

The abstract mentions respiratory responses, yet the study presents no respiratory data—such as ventilation rate, tidal volume, or VO₂. This is misleading and overstates the scope of the research. If no such measures were collected, the reference to respiratory responses should be removed from both the title and the abstract to avoid confusion.

5. Insufficient Reporting of Statistical Power

While the authors reference statistical power in relation to correlation analyses, no information is provided regarding power for the primary comparisons between RE_HL and RE_LL+BFR. Given the relatively small sample size, the study may be underpowered to detect more minor but potentially meaningful differences, particularly in variables like diastolic blood pressure. A clearer discussion of power limitations would help contextualize the results.

6. Overstatement of Clinical Implications

The discussion and conclusion sections make broad claims about the utility of BFR in rehabilitation and clinical populations. These statements are speculative, as the sample did not include older adults, cardiac patients, or individuals with hypertension. Without direct evidence from such groups, these claims should be softened or clearly presented as hypotheses for future research rather than current conclusions.

Minor Issues

• There is some inconsistency in terminology, such as variations between “hemodynamic” and “haemodynamic.” Standardizing spelling throughout the manuscript would improve clarity.
• Some of the figures, particularly Figure 2, are densely labeled and somewhat challenging to interpret. Additional explanation or simplified visuals would enhance readability.

 

Author Response

We thank you for taking the time to review this manuscript and for providing comments that have substantively enriched the work. Please find the responses to your comments on the file attached.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors Dear Authors,

Congratulations for choosing this interesting topic.

Please find below the required corrections identified in the manuscript.




Introduction

• Scope & novelty need sharpening. You motivate BFR safety/efficacy broadly but don’t identify the specific unresolved gap for a full, multi-exercise session (upper + lower, mixed single/multi-joint) with simultaneous hemodynamic/PRP profiling. Add 2–3 sentences explicitly contrasting prior single-exercise studies vs your whole-session design, and state a primary outcome (PRP or SBP?) and a priori non-inferiority/superiority expectation for RE_LL+BFR vs RE_HL.

Methods

• BFR dosing is non-standard. You set cuff pressure to 50% of resting SBP. Best practice is to individualize to % of arterial/limb occlusion pressure (AOP/LOP) accounting for limb circumference and cuff width. Using %SBP can under- or over-restrict across participants. Please:
  • Report actual cuff pressures (mmHg) and justify %SBP with citations, or (preferably) re-express as estimated %AOP (or acknowledge as a limitation and add in future work).
  • Clarify whether the same %SBP was applied to arms and thighs (physiologically they need different %AOP).
• BP/HR measurement details need tightening.
  • BP was manual; specify that readings were taken immediately post-set (not during contraction), the arm used, body position, and the same assessor’s training; note potential underestimation of peak SBP during effort.
  • Define HRmax determination (measured vs age-predicted). If predicted (e.g., 220−age), note its error bounds; otherwise, report the test used.
• Design/analysis clarity.
• Provide a priori power for your primary endpoint (even if post hoc), or acknowledge absence and potential Type II risk.
• Safety monitoring. Describe any adverse-event screening/criteria to terminate sets (symptoms, SBP thresholds), and whether anyone exceeded pre-specified limits.
• Standardize units/formatting (e.g., “PRP” values with units: bpm·mmHg).
• Spellings: “Programme/Program,” “Occlusion,” “Counc”
• Define abbreviations at first use in text and figures (e.g., DBP).

Results

• Report completeness.
  • Include means±SD and 95% CIs for all outcomes at each time point; add absolute deltas from rest and standardized effects with CIs.

Discussion

• Safety thresholds. You cite PRP <30,000 and %HRmax <75% as “safety” cut-offs. Add citations and rephrase as “within commonly used moderate ranges.”
• Results in healthy, trained young men should not be extrapolated to hypertensive/CAD populations without caution; keep those implications as hypotheses consistent with prior RCTs rather than direct inferences.
• The discussion could be strengthened by situating the current findings within the broader context of exercise-induced blood pressure modulation and cardiovascular efficiency during training and detraining periods, as highlighted in recent sport science literature.
• Reference: Applied Sciences https://www.mdpi.com/2076-3417/15/19/10354
  • This paper reported a statistically significant reduction in systolic blood pressure, with no significant differences in resting heart rate or diastolic blood pressure following a structured training intervention.
  • The authors may wish to compare their own hemodynamic results—particularly the direction and magnitude of systolic blood pressure changes—to those observed in this study.
  • Doing so would contextualize whether the observed effects in their BFR and non-BFR protocols align with broader findings of post-training hypotensive adaptations, and whether the mechanism (peripheral vascular conductance vs central cardiac output modulation) is consistent with previous evidence.
• Reference: Sports https://www.mdpi.com/2076-3417/15/19/10354
  • This study documented that resting heart rate, systolic, and diastolic pressures remained relatively stable during a high-frequency transition-period training program in soccer players, suggesting maintenance or mild improvement of cardiovascular efficiency despite a phase normally characterized by detraining.
  • The inclusion of this work would allow the authors to discuss whether hemodynamic stability, rather than change, represents a positive adaptive outcome in certain contexts—especially when load reduction or recovery is the priority.
  • It also provides an interesting contrast to their own results, as the BFR protocol could be evaluated in terms of its capacity to elicit beneficial cardiovascular responses with low mechanical load, compared with conventional endurance or mixed-modality regimens.

Limitations to add (concise)

1. BFR set by %SBP rather than %AOP; 2) unmatched external load/rest; 3) manual, post-exercise BP only; 4) male, trained sample; 5) no lactate or autonomic (HRV) indices; 6) no randomization/familiarization for measurement reactivity on day order if any.

 

Author Response

We thank you for taking the time to review this manuscript and for providing comments that have substantively enriched the work. Please find the responses to your comments on the file attached.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

I have reviewed the authors’ revisions and responses. The changes are thorough and appropriate, enhancing both methodological rigor and presentation quality. The manuscript now reads clearly, aligns with journal standards, and accurately reflects the study’s scope and limitations. I recommend acceptance of the revised version.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors addressed my concerns 

 

Well done!