CARDIOVASCULAR AND PSYCHOLOGICAL RESPONSES TO MAXIMAL EXERCISE IN FRIBROMYALGIA AND CFS

Abstract

436 The mechanisms underlying the persistent fatigue experienced by Fibromyalgia and Chronic Fatigue Syndrome (CFS) patients are unclear. The purpose of this investigation was to describe the cardiovascular and psychological responses to maximal exercise in fibromyalgia and CFS patients. Five (3 fibromyalgia, 2 CFS) (38±4 yrs; 63.7±5.4 kg) patients and 5 control subjects (matched for age, body composition, and physical activity level) completed a graded maximal exercise (MEX) test. Heart rate(HR), blood pressure, and rating of perceived exertion (RPE) were recorded at rest and every two minutes during exercise. Oxygen consumption (VO2) was performed continuously during MEX. Subjects also completed a Profile of Mood States (POMS) questionnaire before, immediately after, and 24 H after MEX. MEX resulted in increases (p<.05) in HR (163±6 b·min-1), SBP (134±16 mm Hg), VO2 (22.9 ml·kg-1·min-1), VE (46.4 L·min-1), and RER (1.02±.05). All six subscales(confusion, depression, fatigue, vigor, anger-hostility, tension-anxiety) of the POMS were unchanged immediately after maximal exercise. In comparison, 24 H after completion of MEX fatigue was increased (p<.05) (≈127%) and vigor reduced (p<.05) (≈57%). Cardiovascular measures responded normally to exercise; however, maximal HR, VO2, and VE measures were lower than controls (p<.05). 24 H after MEX fatigue was greater (p<.05) and vigor lower (p<.05) than normals. These results suggest that the fatigue experienced by fibromyalgia and CFS patients may be related to physiological responses, such as endocrine and immune factors, which persist for 24 or more H after exercise.