Mediating role of physical activity in the relationship between exercise-induced muscle pain and symptom severity in women with fibromyalgia.

BACKGROUND

Individuals with fibromyalgia (FM) exhibit generalized hyperalgesia to pain stimuli, and physical activity (PA) is critical to manage FM symptoms.

PURPOSE: This study examined the relationship between exercise-induced muscle pain, symptom severity, and PA in 28 women with FM.

METHODS

Muscle pain rating (MPR) was assessed during 3 minutes of submaximal isometric handgrip exercise, whereas PA and symptom severity were evaluated via self-report questionnaires. The analysis examined the relationship between the variables, with the specific interest in the mediating role of PA in the relationship between exercise-induced muscle pain and symptom severity.

RESULTS

MPR was positively associated with symptom severity (b = 1.89; 95% CI = 0.01, 3.76; P = .048) and inversely associated with PA levels (b = -0.16; 95% CI = -0.30, -0.03; P = .021). PA levels were inversely associated with symptom severity (b = -7.94; 95% CI = -12.46, -3.42; P = .001). After statistically controlling for PA levels, the relationship between MPR and symptom severity was no longer significant (b = 0.60; Wald 95% CI = -1.05, 2.25; P = .474).

CONCLUSION

Results show the link between the variables, and specifically demonstrate that PA mediates the relationship between exercise-induced muscle pain and symptom severity.