Test-Retest Reliability of the 20-sec Wingate Test to Assess Anaerobic Power in Children with Cerebral Palsy

OBJECTIVE: The aim of this study was to determine the test-retest reliability of the 20-sec Wingate anaerobic test in children with cerebral palsy. DESIGN: Participants were 22 ambulant children with cerebral palsy, with Gross Motor Function Classification System levels I (limitations in advanced motor skills, n = 11), II (limitations in walking, n = 7), and III (walking with walking aids, n = 4), aged 7-13 yrs. All children performed two 20-sec full-out sprint tests on a bicycle ergometer within 1-3 wks. Mean power and peak power (W/kg) were calculated as an estimate of anaerobic power. Test-retest reliability was determined by calculating the intraclass correlation coefficient (ICC) and standard error of measurement (SEM). Values were shown for the total group and Gross Motor Function Classification System I and II/III separately. RESULTS: The test-retest reliability of mean power output was excellent for children with Gross Motor Function Classification System level I (ICC, 0.96; SEM, 5.4%) and II/III (ICC, 0.99; SEM, 6.1%). Peak power output showed a lower reliability in both Gross Motor Function Classification System I (ICC, 0.87; SEM, 9.4%) and II/III (ICC, 0.96; SEM, 11.7%). CONCLUSIONS: Anaerobic testing using a 20-sec Wingate bicycle test is reliable in ambulant school-aged children with cerebral palsy.