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Journal of Athletic Training logoLink to Journal of Athletic Training
. 1998 Apr-Jun;33(2):150–155.

Flexible Magnets Are Not Effective in Decreasing Pain Perception and Recovery Time After Muscle Microinjury

Paul A Borsa 1, Charles L Liggett 1
PMCID: PMC1320403  PMID: 16558503

Abstract

Objective:

To assess the therapeutic effects of flexible magnets on pain perception, intramuscular swelling, range of motion, and muscular strength in individuals with a muscle microinjury.

Design and Setting:

This experiment was a single-blind, placebo study using a repeated-measures design. Subjects performed an intense exercise protocol to induce a muscle microinjury. After pretreatment measurements were recorded, subjects were randomly assigned to an experimental (magnet), placebo (imitation magnet), or control (no magnet) group. Posttreatment measurements were repeated at 24, 48, and 72 hours.

Subjects:

Forty-five healthy subjects participated in the study.

Measurements:

Subjects were measured repeatedly for pain perception, upper arm girth, range of motion, and static force production. Four separate univariate analyses of variances were used to reveal statistically significant mean (±SD) differences between variables over time. Interaction effects were analyzed using Scheffe post hoc analysis.

Results:

Analysis of variance revealed no statistically significant (P > .05) mean differences between conditions for any dependent pretreatment and posttreatment measurements. No significant interaction effects were demonstrated between conditions and times.

Conclusions:

No significant therapeutic effects on pain control and muscular dysfunction were observed in subjects wearing flexible magnets.

Keywords: static magnetic field, magnetohydrodynamic effect, Hall voltage

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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