Pain and Sympathoadrenal Responses to Dynamic Exercise in Women with the Fibromyalgia Syndrome

Abstract

Objectives: To determine whether sympathoadrenal responses during exhaustive bicycling is attenuated in fibromyalgia syndrome [FMS] patients compared to demographically matched healthy normal control [HNC] subjects, and whether pain during exercise is related to sympathoadrenal responses. Another objective was to determine whether exercise exacerbates pain and fatigue in the subsequent days.

Methods: Thirty women [15 FMS, 15 HNC] women matched for age, exercise frequency, and smoking habits bicycled with a stepwise increment in workload until exhaustion. Heart rate, oxygen uptake, and plasma catecholamine concentrations were determined before, during, and after exercise. Pain and perceived exertion were recorded during exercise. Average pain, sleep disturbance, and fatigue were recorded for the seven days preceding the exercise and for Day 1 and Day 7 after the exercise.

Results: Plasma catecholamine concentrations, heart-rate, and oxygen uptake increased similarly during exercise in FMS patients and controls. By contrast, the oxygen uptake at exhaustion was significantly lower in the FMS group. However, when the FMS and HNC subjects were re-matched according to peak oxygen uptake, there were still no significant differences in biological responses were found. Pain increased substantially during exercise in the FMS group. Despite that, no increase in pain or fatigue was observed in the days following exercise.

Conclusion: The FMS patients were less physically fit than the HNCs. The catecholamine and heart rate responses during dynamic exercise were normal in the FMS patients. However, the increase in exercise-induced pain reported in the FMS group could not be explained by an attenuated catecholamine response. Exhaustive dynamic exercise did not induce increased pain or fatigue in patients with FMS.

KEYWORDS:

• Fibromyalgia syndrome
• pain
• catecholamines
• bicycling
• fitness