RESUMEN
OBJECTIVE: To examine beliefs in relation to avoidance of activity in chronic fatigue syndrome (CFS) patients. METHODS: The first phase consisted of modifying an existing chronic pain measure of kinesiophobia-fear of physical movement and activity-and validating it on the CFS population [Tampa Scale of Kinesiophobia-Fatigue (TSK-F); n=129; test-retest: r=.89, P<.001; alpha=.68]. Subscales of Illness Beliefs (alpha=.78) and Beliefs about Activity (alpha=.70) were identified. The second phase consisted of evaluating whether behavioural persistence was predicted by the TSK-F (n=33). Participants were asked to ride an exercise bike for as long as they felt able. RESULTS: Analyses indicated that behavioural persistence did not correlate with maximal heart rate or resting heart rate, level of tiredness, symptom severity, illness identity or emotional distress. However, the TSK-F did correlate highly with distance travelled and added a significant 15% of the variance in distance after adjustments for gender and physical functioning (PF). The TSK-F Beliefs about Activity subscale appears to be the predictive factor, explaining 12% of the variance in excise performance or rather 12% of the avoidance of exercise. CONCLUSION: Beliefs about Activity appear to be an important variable in predicting behaviour and avoidance of exercise. As avoidance has been suggested as a key to the maintenance of symptoms, disability and distress in CFS patients, this research has important theoretical, clinical and research implications.