Exercise testing in children and adolescents with chronic fatigue syndrome

The objective of this study was to evaluate exer- cise capacity in children and adolescents diag- nosed with Chronic Fatigue Syndrome (CFS). We examined 20 patients (12 girls and 8 boys; mean age 14.9±3.7 years) diagnosed with CFS. Exercise capacity was measured using a maximal exercise test on a bicycle ergometer and an expired gas analysis system. Fatigue was assessed using a questionnaire and a daily activity diary was used todescribe activitiesforthreedays.Z-scores were calculated using age- and sex-matched reference values. Z-scores in children and adolescents with CFS were -0.33±1.0 (p= 0.17) for peak oxygen uptake, -1.13± 1.41 (p =0.002) for relative peak oxygen uptake (ml/kg/min) and -0.93± 1.29 (p =0.07) for maximal work load. Both heart rate and blood pressure at peak performance were significantly reduced compared to reference val- ues. Fatigue levels were significantly positively associated with age and negatively with blood pressure at peak exercise (p