ARM CRANKING VERSUS WHEELCHAIR PROPULSION FOR TESTING AEROBIC FITNESS IN CHILDREN WITH SPINA BIFIDA WHO ARE WHEELCHAIR DEPENDENT

Objective: To determine the best test performance and feasibility using a Graded Arm Cranking Test vs a Graded Wheelchair Propulsion Test in young people with spina bifida who use a wheelchair, and to determine the reliability of the best test. Design: Validity and reliability study. Subjects: Young people with spina bifida who use a wheelchair. Methods: Physiological responses were measured during a Graded Arm Cranking Test and a Graded Wheelchair Propulsion Test using a heart rate monitor and calibrated mobile gas analysis system (Cortex Metamax). For validity, peak oxygen uptake (VO2peak) and peak heart rate (HRpeak) were compared using paired t-tests. For reliability, the intraclass correlation coefficients, standard error of measurement, and standard detectable change were calculated. Results: VO2peak and HRpeak were higher during wheelchair propulsion compared with arm cranking (23.1 vs 19.5 ml/kg/min, p=0.11; 165 vs 150 beats/min, p < 0.05). Reliability of wheelchair propulsion showed high intra-class correlation coefficients (ICCs) for both VO2peak (ICC= 0.93) and HRpeak (ICC = 0.90). Conclusion: This pilot study shows higher HRpeak and a tendency to higher VO2peak in young people with spina bifida who are using a wheelchair when tested during wheelchair propulsion compared with arm cranking. Wheelchair propulsion showed good reliability. We recommend performing a wheelchair propulsion test for aerobic fitness testing in this population.