Immediate Effects of Dynamic Cupping on Shoulder Active Range of Motion of Senior Male Handball Players: A Randomized Controlled Trial

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript explores the immediate effects of dynamic cupping on shoulder active range of motion (AROM) in senior male handball athletes through a randomized controlled trial. The integration of thorough statistical analysis and focus on a relevant athletic population is commendable, contributing to the limited research on the benefits of cupping therapy.

1. The authors should adequately detail the mechanism underlying the observed AROM improvements, strengthening the discussion of the results.

2. Figures lack sufficient resolution, and the axes in Figure 3 are poorly labeled. The authors should include error bars or confidence intervals in the graphical representation of results, providing more clarity and supporting the statistical findings.

3. The study evaluates only the short-term effects of dynamic cupping. The authors should include long-term follow-ups to assess the sustainability of the observed benefits. If this is not possible, please mention it in the future work part.

4. The methodology section would benefit from further elaboration, particularly regarding the randomization process and potential biases introduced using a convenience sample.

5. The authors should explore the potential placebo effect associated with cupping therapy, which could influence the observed differences between groups.

6. Further insights into how dynamic cupping could be integrated with other physiotherapeutic modalities to add pragmatic relevance to the findings.

7. In the results, the authors strongly suggested that providing a visual representation of inter-group differences (e.g., through bar charts or confidence intervals) would enhance the impact of the results.

Author Response

Reviewer 1:

1. The authors should adequately detail the mechanism underlying the observed AROM improvements, strengthening the discussion of the results.

Answer:  Thank you for your comment. We added this paragraph on discussion:

“The observed improvements in shoulder AROM following dynamic cupping therapy are likely due to several physiological mechanisms. First, dynamic cupping enhances local blood flow by creating a vacuum effect, which promotes vasodilation and im-proves tissue perfusion. This increase in blood circulation delivers more oxygen and nutrients to the affected area, aiding in muscle recovery and reducing stiffness. Second, the technique facilitates myofascial release by loosening adhesions and improving the viscoelastic properties of the fascia and muscle tissue. This reduces mechanical re-strictions and enhances mobility. Third, dynamic cupping may stimulate peripheral nerve endings, modulating the sensory input to the central nervous system and promoting muscle relaxation. Finally, the combination of negative and positive pressure applied during dynamic cupping likely reduces muscle tension and improves elasticity, contributing to the observed increases in joint mobility.

 

 

1. Figures lack sufficient resolution, and the axes in Figure 3 are poorly labeled. The authors should include error bars or confidence intervals in the graphical representation of results, providing more clarity and supporting the statistical findings.

Answer:  Thank you for your comment. In our perspective the figures have very high resolution and their size can be increased maintaining the quality of the image. Figures 2 and 3 already include error bars corresponding to 95% Confidence Intervals (appearing vertically from dots, which are the estimates).

 

1. The study evaluates only the short-term effects of dynamic cupping. The authors should include long-term follow-ups to assess the sustainability of the observed benefits. If this is not possible, please mention it in the future work part.

Answer:  Thank you for your comment. It wasn't possible. It was added in limitations and conclusions.

 

1. The methodology section would benefit from further elaboration, particularly regarding the randomization process and potential biases introduced using a convenience sample.

Answer:  Thank you for your comment. We added this paragraph on methodology: “After completing the socio-demographic and clinical questionnaire, the players were randomly assigned to two designated groups, the Intervention Group (IG; n = 40) (dynamic cupping therapy) and the Control Group (CG; n = 40) (no intervention group), using GraphPad software (www.graphpad.com/quickcals), which ensures unbiased allocation by generating a random sequence. This randomization process minimizes the risk of systematic bias in group assignments and enhances the validity of our findings. However, the use of a convenience sample consisting of 80 senior male handball athletes introduces potential limitations. The representativeness of this sample may be constrained, potentially affecting the generalizability of the results. The implications of this limitation are discussed further in the Discussion section.”

We added this paragraph on discussion: “The use of a convenience sample, although practical, introduces potential biases that warrant consideration. This sampling approach limits the generalizability of the findings to broader athletic populations or other age groups. While randomization mitigates allocation bias within the study, the convenience sample may inadvertently favor participants with specific characteristics (e.g., access to handball teams in selected regions). Future studies should aim to recruit more diverse and representative samples to strengthen the applicability of the results.”

 

1. The authors should explore the potential placebo effect associated with cupping therapy, which could influence the observed differences between groups.

Answer:  Thank you for your question. We added this paragraph on discussion:

“The results of this study indicate that dynamic cupping therapy may have a positive effect on AROM. However, it is essential to consider the potential influence of the placebo effect on the outcomes observed. In this study, while the CG did not receive any intervention, the IG might have experienced an enhanced placebo response due to their perception of receiving therapy. This could have contributed to the improvements in AROM across all shoulder movements. To more accurately assess the true effects of dynamic cupping therapy, future research should include a placebo control group that receives a sham cupping treatment or another inactive intervention. This approach would help clarify whether the observed improvements are genuinely due to the specific effects of dynamic cupping therapy or if they are influenced by placebo-related factors.”

 

1. Further insights into how dynamic cupping could be integrated with other physiotherapeutic modalities to add pragmatic relevance to the findings.

Answer:  Thank you for your comment. While we acknowledge the potential benefits of exploring the integration of dynamic cupping with other physiotherapeutic modalities, the primary objective of this study was to assess the immediate effects of dynamic cupping on shoulder AROM in senior male handball athletes. Considering the results of our study we have already pointed in the discussion that “Coaches, physiotherapists, and sports medicine professionals may consider incorporating dynamic cupping as a non-invasive, time-efficient modality to complement other therapeutic and performance-enhancing practices. Moreover, we agree that future studies could investigate the synergistic effects of dynamic cupping with other physiotherapeutic interventions. This has been noted as a potential research line for future research in the revised manuscript (Conclusion):

“Additionally, comparative studies examining the combined effects of dynamic cupping with other physiotherapeutic modalities, such as stretching or manual therapy, could provide deeper insights into its synergistic benefits.”

 

1. In the results, the authors strongly suggested that providing a visual representation of inter-group differences (e.g., through bar charts or confidence intervals) would enhance the impact of the results.

Answer: Thank you for your comment. The effect-size (rank-biserial correlation coefficients) and its 95% confidence intervals for inter- and intra-group comparisons were added in table 2, evidencing the differences in the magnitude of the effect for each movement in both groups. This clearly presents the magnitude of the effect of the intervention (intervention or control).

Reviewer 2 Report

Comments and Suggestions for Authors

DEAR AUTHORS:

After read carefully the article entitled” Immediate effects of dynamic cupping on shoulder active range of motion of senior male handball athletes: A randomized controlled trial”, some ideas are proposed in order to improve the final versión

KING REGARDS

 

Comments for author File: Comments.pdf

Comments on the Quality of English Language

DEAR:

After read carefully the article entitled” Immediate effects of dynamic cupping on shoulder active range of motion of senior male handball athletes: A randomized controlled trial”, some ideas are proposed in order to improve the final versión

KING REGARDS

 

Author Response

Reviewer 2: After read carefully the article entitled” Immediate effects of dynamic cupping on shoulder active range of motion of senior male handball athletes: A randomized controlled trial”, some ideas are proposed in order to improve the final version.

KING REGARDS

 

 Title:

• L 3: Title: Immediate effects of dynamic cupping on shoulder active range 2 of motion of senior male handball athletes: A randomized controlled
• BETTER PLAYERS THAN ATHLETES
• Answer: Thank you for your comment. It was modified in all document.

 

Abstract:

• L25-L28: The conclusions are expressed in two different sentences, please unify both sentences for a better understanding of the conclusions.
• Answer: Thank you for your comment. It was modified.
•  
• L 36. Between the first two paragraphs, include one connestion sentence, in general the paragraphs are no connected
• Answer: Thank you for your comment. It was rewrote:

“Handball is a team sport in which the aim of each team is to invade the opponent's field, occupying common spaces, with the continuous struggle for ball possession and goal pursuit. The attack and defense sequences of both teams go through complex and unpredictable tactical and technical plans that may influence the players' technical and tactical behaviors [1-4].

• These dynamic and high-intensity demands place significant stress on players' shoulders, particularly during overhead movements common in handball. Shoulder adaptations resulting from such practice include increased medial rotation torque and an increased range of motion in external rotation. However, this is often accompanied by a decrease in total shoulder range of motion and internal rotation range of motion. These factors can contribute to changes in shoulder mobility, particularly in handball players who experience reduced flexibility [5].”

 

 

Introduction:

• L47: Please connect both paragraphs to avoid a paragraph being composed of only one sentence
• Answer: Thank you for your comment. It was rewrote:

“Over time, there has been a growing interest in the application of ancient treatment techniques, such as cupping therapy [7]. Although scientific evidence on the use of cupping by athletic populations is scarce [8], existing research suggests that cupping may be beneficial for a variety of musculoskeletal conditions [7]. By improving local microcirculation and enhancing the transport of metabolic by-products such as lactate, cupping can aid post-exercise metabolic recovery [9], making it a promising intervention for athletic populations.”

• L51: Delete could bring and preplace it for: Therefore, the use of cupping therapy may be beneficial for handball players who are predisposed to shoulder injuries.
• Answer: Thank you for your comment. It was rewrote:
• “Therefore, the use of cupping therapy may be beneficial for handball players who are predisposed to shoulder injuries.”
•  
• L68-70: Rewrite the sentence for better understanding. For example: The dynamic cupping technique promotes negative vacuum pressure 68 while inducing positive pressure due to the superficial massage performed 69 with the cup.
• Answer: Thank you for your comment. It was rewrote:

“Dynamic cupping involves the creation of negative vacuum pressure combined with positive pressure from the superficial massage performed by the suction cup. This technique aims to enhance blood and lymph flow, facilitating the removal of toxins and improving cellular nutrition [15,16].”

•  
• L73: Please check if there is a double space before “promoting”.
• Answer: Thank you for your comment. It was changed.
•  
• L74: Please check if there is a double space before “muscle”.

Answer:  Thank you for your comment. It was changed.

•  
• L78: As authors have mentioned the different cupping types, you may consider specifying the type of cupping therapy that you have performed for this study.
• Answer: Thank you for your comment. The following phrase was rewrote:
• “Massage cupping or dynamic cupping involves suctioning the skin and moving the suction cup along the surface of the skin, while maintaining suction [14].”
• In the document, we used the term dynamic cupping.

 

• L 88: (ch Involving Human Subjects) ch Involving Human Subjects) ch Involving Human Subjects)

BETTER PARTICIPANTS THAN SUBJECT S

Answer:  Thank you for your comment. It was changed.

 

-L 88: HELSINKI DECLARATION

INCLUDE This reference: https://pubmed.ncbi.nlm.nih.gov/24141714/

Answer:  Thank you for your comment. It was added.

 

-L 90: Table 2. Intra and inter-group differences in shoulder AROM before (M0) and after intervention (M1).

Include effect size between both groups, magnitude of change and mechanical inference

Answer: Thank you for your comment. The effect-size (rank-biserial correlation coefficients) and its 95% confidence intervals for inter- and intra-group comparisons were added in table 2, evidencing the differences in the magnitude of the effect for each movement in both groups. This clearly presents the magnitude of the effect of the intervention (intervention or control).

 

Methods:

• L117: Please check that ® it is written in superindex along the text.

Answer:  Thank you for your comment. It was checked.

 

• L156: Please delete “for”.

Answer:  Thank you for your comment. It was changed.

•  
• LINE 165: Social Sciences (SPSS 165 v.25.0)
• ® IN SUPERINDEX

Answer:  Thank you for your comment. It was changed.

 

• L179: Table 1. Comparison between the groups in terms of biometric characteristics

 

INCLUDE EFFECT SIZE BETWEEN BOTH GROUPS

Answer: Thank you for your comment. The effect-size (rank-biserial correlation coefficients) and its 95% confidence intervals for inter- and intra-group comparisons were added in table 2, evidencing the differences in the magnitude of the effect for each movement in both groups. This clearly presents the magnitude of the effect of the intervention (intervention or control).

Results:

• In table 2 please add the meaning of (º) at the bottom of the table.

Answer:  Thank you for your comment. It was added.

•  

Discussion:

• L264: Please provide information of the meaning of “C”.
• Answer: Thank you for your comment. The following phrase was rewrote:
• “Elasticity is an essential property of muscle tissue, contributing to its ability to stretch and maintain tissue integrity during movement [32]. The resistance to muscle traction during stretching is influenced by structural proteins such as titin, which help modulate the elastic and viscoelastic properties of skeletal muscle fibers [33].”
•  
• L273-279: Consider whether the paragraph on flexibility is mandatory in the discussion.

Answer:  Thank you for your comment. It was removed.

•  
• I would suggest reorganizing the discussion section so that the mechanisms of action by which the results have been found are clearly visible.

Answer:  Thank you for your comment. The discussion was reorganized and we added the following mechanisms of action:

“The observed improvements in shoulder AROM following dynamic cupping therapy are likely due to several physiological mechanisms. First, dynamic cupping enhances local blood flow by creating a vacuum effect, which promotes vasodilation and im-proves tissue perfusion. This increase in blood circulation delivers more oxygen and nutrients to the affected area, aiding in muscle recovery and reducing stiffness. Second, the technique facilitates myofascial release by loosening adhesions and improving the viscoelastic properties of the fascia and muscle tissue. This reduces mechanical re-strictions and enhances mobility. Third, dynamic cupping may stimulate peripheral nerve endings, modulating the sensory input to the central nervous system and promoting muscle relaxation. Finally, the combination of negative and positive pressure applied during dynamic cupping likely reduces muscle tension and improves elasticity, contributing to the observed increases in joint mobility.

 

• L 284: Include practical applications and future research lines

Answer:  Thank you for your comment. It was added on discussion:

“This technique could be integrated into regular training or rehabilitation programs to address mobility restrictions, reduce muscle stiffness, and potentially enhance athletic performance. Coaches, physiotherapists, and sports medicine professionals may con-sider incorporating dynamic cupping as a non-invasive, time-efficient modality to complement other therapeutic and performance-enhancing practices.”

future research lines

“However, more studies are needed, with a good methodological basis, to confirm or refute the results obtained in this investigation and highlight the mechanisms under-lying these effects. It is suggested that future studies analyse the long-term effects of cupping, especially randomized controlled studies with more groups (containing placebo group and other intervention techniques combined or not with cupping), including intervention in females and in other samples (e.g. athletes from other sports). The assessment of the effects of different types of cupping (e.g. static, dynamic), with different intervention duration sessions (e.g. 5, 10, 15 and 20 minutes), longer intervention period (one week or two weeks) and with longer follow-ups. Future studies should aim to recruit more diverse and representative samples to strengthen the applicability of the results. Additionally, comparative studies examining the combined effects of dynamic cupping with other physiotherapeutic modalities, such as stretching or manual therapy, could provide deeper insights into its synergistic benefits.”

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have addressed all the concerns raised by the reviewer. The manuscript can now be accepted.