آیا سندرم خستگی مزمن ورزش هراسی است؟مطالعه مورد شاهدی

Objective The aim of this study was to test whether patients with chronic fatigue syndrome (CFS) have an exercise phobia, by measuring anxiety-related physiological and psychological reactions to ordinary activity and exercise. Methods Patients and healthy but sedentary controls were assessed over 8 h of an ordinary day, and before, during and after an incremental exercise test on a motorised treadmill. To avoid confounding effects, those with a comorbid psychiatric disorder were excluded. Heart rate, galvanic skin resistance (GSR) and the amount of activity undertaken were measured, along with state and trait measures of anxiety. Results Patients with CFS were more fatigued and sleep disturbed than were the controls and noted greater effort during the exercise test. No statistically significant differences were found in either heart rate or GSR both during a normal day and before, during and after the exercise test. Patients with CFS were more symptomatically anxious at all times, but this did not increase with exercise. Conclusion The data suggest that CFS patients without a comorbid psychiatric disorder do not have an exercise phobia.

The cognitive–behavioural model for chronic fatigue syndrome (CFS) suggests that patients become trapped in a vicious cycle perpetuated by maladaptive behaviours, cognitive misinterpretations and illness beliefs that maintain symptoms and disability [1]. Graded exercise therapy (GET) has been advocated for CFS, on the basis that CFS is maintained by both the avoidance of activity and deconditioning [2] and [3]. Two systematic reviews have concluded that there is high quality evidence of efficacy of GET in adult outpatients [4]. Yet, many patients can drop out of GET or not even start it, and this may be related to a fear of exercise, which is reported by the majority of CFS patients [5]. Fifty percent of 2338 members of an ME self-help charity held the belief that GET was “damaging” [6]. Of 105 patients reporting their experience of exercise, 55% believed that their recovery would be facilitated by limiting their physical activity [7]. Even some doctors have “…deep concerns over the current application of graded exercise programmes…” [8]. Kinesiophobia is the fear of physical movement or activity [9], and the concept is derived from studies of patients with chronic pain syndromes [10] and [11]. The Tampa Scale of Kinesiophobia (TSK) has been developed in pain patients as a valid and reliable measure of the fear of exercise and has been found to be a predictor of distress and disability [10]. It has been adapted by both Silver et al. [9] and Nijs et al. [12] for use in CFS patients. Using the new TSK-F scale, Silver et al. found that fear of exercise was linked to reduced exercise performance on a bicycle ergometer and explained 15% of the variance in distance cycled. They also found that preexercise anxiety was much higher than postexercise anxiety. Nijs et al. found that 47 of 64 CFS patients (72%) had a TSK score for fatigue of over 37, in their view, indicating kinesiophobia [12]. A phobia is a “marked and persistent fear that is excessive or unreasonable, cued by the presence or anticipation of a specific object or situation” [13]. Exposure to the stimulus provokes an immediate anxiety response, with consequent avoidance or intense anxiety [13]. We tested the hypothesis that CFS patients have a phobic avoidance of exercise (kinesiophobia) [9] that related both to the activities of everyday living and to a specific exercise challenge. We expected that if these patients do suffer from such a phobia, then they would show an associated abnormal physiological arousal in anticipation of and/or during exposure to their feared stimulus: an exercise challenge [14] and [15]. We also expected the CFS patients to be less active (more avoidant) than the controls and to have higher anxiety scores, both before and after the exercise [9] and [13]. To test for the presence of an exercise phobia, we hypothesized the following concerning CFS in comparison to controls: (a) they would be generally more anxious; (b) they would have an increase in state anxiety in both anticipation and response to exercise; (c) they would have physiological evidence of greater arousal, as measured by a greater increased heart rate, and a greater decrease in galvanic skin resistance (GSR) during routine daily activities and in response to exercise; and (d) they would be more likely to avoid physical activity in general and exercise in particular. If a phobia of either exercise or activity were present, then we would expect to see both increased symptomatic anxiety in anticipation of the feared stimulus and a physiological reaction in the face of the stimulus [13], [14] and [15].