CRD summary

This review evaluated the impact of whole-body vibration on jump performance and muscle strength. The authors concluded that whole-body vibration has no or only limited effect. The conclusions follow from the results. However, limitations in the reporting of the review process and the lack of a validity assessment make it difficult to assess the reliability of these conclusions.

Authors' objectives

To review the evidence for the effects of whole–body vibration (WBV) on strength and jump performance.

Searching

MEDLINE, PubMed, SPORTDiscus and EBSCO were searched from inception to August 2005; the search terms were reported. Only published full-length articles of original experiments were eligible for inclusion. Conference abstracts and proceedings were excluded. The reference lists of retrieved articles were checked.

Study selection

Assessment of study quality

The authors did not state that they assessed validity.

Data extraction

The authors did not state how the data were extracted for review, or how many reviewers performed the data extraction.

Methods of synthesis

Results of the review

Twelve studies (n=479) were included in the review. Four studies compared WBV alone with a control group performing identical exercises (n=79). Four studies compared WBV alone with a passive control group (n=154). Three studies compared WBV with both a passive control group and a strength training control group (n=179). One study compared WBV with a control group performing identical exercises, a passive control group and a strength training control group (n=67).

WBV compared with control group performing identical exercise (5 studies).

Only one study reported significant differences between the groups. This study found significantly improved jump height, isometric and dynamic strength, but no statistical data were reported. This study was performed on untrained women with a lower fitness level than the mixed groups included in the other studies.

WBV compared with passive control (8 studies).

The majority of studies found that WBV was significantly superior in improving jump height and strength.

WBV compared with strength training exercise (4 studies).

Most studies found no significant difference between the jump height and strength of participants using WBV and those using strength training.

Authors' conclusions

WBV provides no or only minor additional effects on muscle strength and jump performance, at least in healthy fit people. The design of studies in older or sedentary groups was such that it was impossible to isolate the effects of WBV.

CRD commentary

Inclusion criteria for the intervention, study design and outcomes were clear. Inclusion criteria for the participants were undefined, although the authors took account of the wide variation in patient characteristics when drawing their conclusions. A broad search strategy was carried out, but the search was restricted to articles published in full and it is unclear whether language restrictions were applied, therefore important data might have been missed. There was insufficient information about the data extraction and study selection processes to rule out the possibility of error and bias. A validity assessment does not appear to have been carried out and there is insufficient information to determine the methodological quality of the included studies.

The decision to use a narrative synthesis was appropriate given the heterogeneity of the included studies. However, the inclusion of studies with control groups that did not perform identical exercises limits the ability to draw meaningful conclusions about the impact of WBV, as opposed to the impact of the exercises performed. Statistical measures of association were not reported for individual studies, making it difficult to assess the statistical significance of the results. Given the limited reporting of review methods and the lack of a validity assessment, the reliability of the authors’ conclusions is unclear.

Implications of the review for practice and research

Practice: The authors stated that there is no evidence to support recommending WBV training, at least in healthy fit people.

Research: The authors did not state any recommendations for research.

Funding

Swedish Centre for Sports Research.

Bibliographic details

Nordlund M M, Thorstensson A. Strength training effects of whole-body vibration? Scandinavian Journal of Medicine and Science in Sports 2007; 17(1): 12-17. [PubMed: 17038159]

Original Paper URL

http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0838.2006.00586.x/abstract

Indexing Status

Subject indexing assigned by NLM

MeSH

Exercise /physiology; Humans; Muscle Strength; Physical Education and Training /methods; Vibration

AccessionNumber

12007009044

Database entry date

01/12/2008

Record Status

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.