This systematic review investigated the effects of massage guns on performance and recovery in healthy and unhealthy populations. Eleven studies were included, with most exhibiting a moderate risk of bias. Massage guns were found to be effective in improving short-term range of motion (ROM) and flexibility (statistically significant improvements were reported in multiple studies, though specific values were not provided in the analysis). However, they showed no improvement, or even a decrease, in strength, balance, acceleration, agility, and explosive activities. For recovery, massage guns showed some benefits in short-term outcomes, but no significant differences were observed in contraction time, rating of perceived exertion, or lactate concentration. The physiological mechanisms remain uncertain.
The systematic review demonstrates a clear distinction between correlation and causation. While massage guns show a correlation with improved short-term range of motion, flexibility, and recovery, the review correctly avoids claiming a causal relationship for strength, balance, or explosive activities, where performance either remained unchanged or decreased. This cautious approach is appropriate given the limitations of the included studies.
The practical utility of massage guns appears limited to specific contexts. The findings suggest potential benefits for improving flexibility and aiding recovery, which could be useful for athletes and individuals undergoing rehabilitation. However, the lack of positive effects on strength and power, coupled with potential performance decrements, limits their application for pre-competition warm-ups or performance enhancement in explosive activities. The review appropriately places these findings within the context of existing literature on vibration therapy, but acknowledges the novelty of massage guns and the need for more research.
The review provides clear guidance for practitioners regarding the potential use of massage guns for flexibility and recovery, suggesting specific application parameters (frequency, duration). However, it rightly emphasizes the uncertainties surrounding the physiological mechanisms and the need for further research to confirm these recommendations. The review also responsibly highlights contraindications and potential adverse effects, promoting safe and informed application.
Critical unanswered questions remain regarding the long-term effects of massage guns, the optimal application parameters for different populations and outcomes, and the precise physiological mechanisms involved. The review acknowledges that the methodological limitations of the included studies, particularly the moderate risk of bias and small sample sizes, fundamentally affect the strength of the conclusions. Further high-quality, randomized controlled trials with diverse populations and standardized protocols are essential to address these uncertainties and provide more definitive evidence-based guidelines for the use of massage guns.
The abstract clearly states the purpose of the systematic review, which is to determine the effects of massage guns on performance and recovery in both healthy and unhealthy populations.
The abstract concisely summarizes the methodology, including the databases searched and the eligibility criteria (P.I.C.O.S.).
The abstract presents the main findings, including both positive and negative effects of massage guns, providing a balanced overview.
The abstract provides a clear and concise conclusion, summarizing the overall findings and offering recommendations.
This is a medium-impact suggestion. While the abstract mentions the risk of bias, it could be improved by briefly stating the overall quality of evidence based on the risk of bias assessment. This belongs in the abstract as it provides a critical appraisal of the included studies, influencing the interpretation of the findings.
Implementation: Add a sentence summarizing the overall quality of evidence (e.g., "The overall quality of evidence was moderate due to the risk of bias in the included studies.").
This is a low-impact suggestion. The abstract could benefit from quantifying the main results with some key numerical data (e.g., effect sizes or percentage improvements) to provide a more precise summary of the findings. This belongs in the abstract to enhance the informativeness and impact of the findings.
Implementation: Include key numerical data, such as effect sizes or percentage improvements, for the main outcomes (e.g., "Massage guns improved flexibility by X% (p < 0.05).").
This is a low-impact suggestion. While the abstract mentions healthy and unhealthy populations, it could be slightly more specific about the types of populations included (e.g., athletes, individuals with specific conditions). This is important for the abstract as it helps readers quickly assess the relevance of the review to their interests.
Implementation: Specify the types of populations included (e.g., "...in athletes and individuals with musculoskeletal pain.").
The introduction provides a concise historical overview of percussive and vibration therapy, tracing its origins from ancient Greece to modern applications.
The introduction clearly establishes the increasing popularity and versatility of massage guns in both clinical and sports contexts.
The introduction effectively highlights the gap in knowledge and the need for a systematic review to guide practitioners on the use of massage guns.
The introduction succinctly states the aim of the systematic review, providing a clear focus for the study.
The introduction mentions a wide range of health issues for which vibration therapy interventions have shown to be viable, demonstrating the broad applicability of the topic.
This is a medium-impact suggestion. The introduction could be strengthened by more explicitly connecting the historical context of vibration therapy to the modern use of massage guns. While it mentions the evolution of the interventions, it could more clearly bridge the gap between traditional methods and the specific focus of this review. This belongs in the introduction as it would provide a more cohesive narrative and strengthen the rationale for studying massage guns.
Implementation: Add a sentence or two that explicitly links the historical use of vibration therapy to the emergence of massage guns (e.g., "Building upon this historical foundation, modern technology has led to the development of massage guns, which offer a portable and targeted approach to percussive therapy.").
This is a medium-impact suggestion. The introduction could benefit from briefly mentioning the proposed mechanisms of action of massage guns. While a detailed discussion belongs in later sections, a brief overview in the introduction would provide a more complete picture of the topic and further justify the need for the review. This belongs in the introduction to provide a more comprehensive overview of the topic and its underlying principles.
Implementation: Add a sentence or two briefly outlining the proposed mechanisms of action (e.g., "Massage guns are thought to exert their effects through a combination of mechanical pressure, vibration, and neurophysiological responses, influencing muscle tone, blood flow, and pain perception.").
This is a low-impact suggestion. The introduction could slightly expand on the "little information to guide practitioners" statement by briefly mentioning the specific types of information that are lacking (e.g., optimal parameters, specific applications). This is important for the introduction to further clarify the need for the review and its potential contributions.
Implementation: Expand on the "little information" statement by adding examples (e.g., "...there is still little information to guide practitioners regarding optimal treatment parameters, specific applications, and potential contraindications.").
The section clearly states that the review was conducted according to the PRISMA statement and registered with PROSPERO, indicating adherence to established guidelines for systematic reviews.
The section provides a comprehensive description of the search strategy, including the databases searched, keywords used, and the P.I.C.O.S. model employed. This enhances the transparency and reproducibility of the review.
The section clearly defines the inclusion and exclusion criteria, providing a detailed description of the types of studies, participants, interventions, and outcomes considered. This ensures that the review focused on relevant studies.
The section describes the study selection process, including the involvement of two independent authors and a third reviewer for arbitration, minimizing bias in the selection of studies.
The section outlines the data extraction process, including the use of a standardized spreadsheet and the involvement of two authors to ensure consistency and accuracy.
The section specifies the primary and secondary outcomes considered in the review, providing a clear framework for the analysis of the included studies.
The section describes the risk of bias assessment, utilizing established tools (Cochrane's RoB 2 and ROBINS-I) and involving multiple authors to ensure a thorough evaluation of the methodological quality of the included studies.
This is a medium-impact suggestion. While the section mentions contacting authors for missing data, it doesn't specify how many attempts were made or the timeframe for follow-up. This belongs in the Methods section to ensure transparency and assess the completeness of the data.
Implementation: Specify the number of contact attempts and follow-up timeframe (e.g., "Authors were contacted via email up to three times over a four-week period.").
This is a low-impact suggestion. The section could briefly mention the software used for managing references and data (e.g., EndNote, Excel). While not essential, it adds a detail that enhances transparency. This belongs in the Methods section to improve reproducibility.
Implementation: Include the specific software versions used (e.g., "EndNote 20 was used for reference management, and Microsoft Excel (version 16) was used for data extraction and analysis.").
This is a low-impact suggestion. While the section mentions using an Excel spreadsheet for data analysis, it could be more specific about the type of analysis performed (e.g., descriptive statistics, meta-analysis). This belongs in the Methods section to clarify the analytical approach.
Implementation: Specify the type of data analysis performed (e.g., "Data were analyzed using descriptive statistics, including means and standard deviations. A meta-analysis was planned but not conducted due to heterogeneity in study designs and outcomes.").
The section clearly presents the results of the database searches, including the number of records identified, screened, and included, providing a transparent overview of the study selection process.
The section effectively utilizes a PRISMA flow diagram (Figure 3) to visually summarize the study selection process, enhancing clarity and understanding.
The section provides a detailed summary of the risk of bias assessment, using established tools (RoB 2 and ROBINS-I) and presenting the results both narratively and visually (Figure 4).
The section synthesizes the characteristics of the included studies, providing information on geographical distribution, publication types, funding sources, conflicts of interest, publication years, study designs, comparator groups, outcomes, intervention details, and participant demographics.
The section presents a detailed table (Table 2) summarizing the results of individual studies, including objectives, participant characteristics, cohorts, outcomes, and key findings. This table facilitates a comprehensive comparison of the included studies.
This is a medium-impact suggestion. While the section mentions the number of included studies, it could be improved by explicitly stating the *types* of studies included (e.g., randomized controlled trials, crossover trials). This belongs in the Results section as it provides immediate context for the type of evidence synthesized. The PRISMA flow diagram shows included vs. excluded, but doesn't specify the types of studies *within* the included group.
Implementation: Add a sentence specifying the types of studies included (e.g., "The 11 included studies comprised eight randomized controlled trials and three crossover trials.").
This is a medium-impact suggestion. While Table 2 summarizes individual study results, the main text of the Results section could benefit from a more structured presentation of the *overall* findings, organized by outcome categories (e.g., range of motion, strength, fatigue). This belongs in the Results section to improve clarity and facilitate understanding of the aggregated results. Currently, the synthesis focuses on study characteristics, not the synthesis of *results* across studies.
Implementation: Restructure the 'Studies' Synthesis' subsection to organize findings by outcome categories, summarizing the overall results for each outcome (e.g., "For range of motion, seven studies reported significant improvements..., while two studies found no significant effects...").
This is a low-impact suggestion. The section could briefly mention the statistical methods used to synthesize the results (e.g., narrative synthesis, meta-analysis if applicable). This belongs in the Results section to provide context for the interpretation of the findings. While the Methods section *mentions* qualitative and quantitative synthesis, the Results section should state *which* was actually used.
Implementation: Add a sentence indicating the type of synthesis performed (e.g., "Due to heterogeneity in study designs and outcomes, a narrative synthesis of the results was conducted.").
This is a low-impact suggestion. While Figure 4 presents the risk of bias assessment, the text could briefly *summarize* the overall risk of bias (e.g., "most studies were judged to be at moderate risk of bias"). This belongs in the Results section to provide a concise overview of the methodological quality of the included studies. While the information is *in* Figure 4, the text should briefly summarize it.
Implementation: Add a sentence summarizing the overall risk of bias (e.g., "Overall, the majority of included studies were assessed as having a moderate risk of bias.").
Figure 3. PRISMA flow diagram highlighting the selection process for the studies included in the systematic review. Abbreviations: WBV-whole body vibration.
Figure 4. Risk of bias: (a) randomized trials studies assessment; (b) percentage distribution in randomized trials; (c) nonrandomized trials studies assessment; (d) percentage distribution in non- randomized trials. [34-44].