Predicting peak oxygen uptake from submaximal exercise after spinal cord injury

摘要

The purpose of this study was to determine the validity of the 6-minute arm ergometry test (6MAT) in predicting peak oxygen consumption (VO2peak) in individuals with chronic spinal cord injury (SCI). Fifty-two individuals with chronic SCI (age 38±10 years; American Spinal Injury Association Impairment Scale A-D, neurological level of injury C1-L2, years post-injury 13±10 years) completed an incremental arm ergometry VO2peak test and a submaximal 6MAT. Oxygen consumption data from both tests were used to create a predictive equation with regression analysis. Subsequently, a cross-validation group of an additional ten individuals with SCI (age 39±13 years; AIS A-D, NLI C3-L3, YPI 9±9 years) were used to determine the predictive power of the equation. All participants were able to complete both the VO2peak and 6MAT assessments. Regression analysis yielded the following equation to predict VO2peak from end-stage 6MAT VO2: VO2peak (mL·kg⁻¹·min⁻¹) = 1.501(6MAT VO2) – 0.940. Correlation between measured and predicted VO2peak was excellent (r=0.89). No significant difference was found between measured (17.41±7.44 mL·kg⁻¹·min⁻¹) and predicted (17.42±6.61 mL·kg⁻¹·min⁻¹) VO2peak (p=0.97). When cross-validated with a sample of ten individuals with SCI, correlation between measured and predicted VO2peak remained high (r=0.89), with no differences between measured (18.81 ± 8.35 mL·kg⁻¹·min⁻¹) and predicted (18.73 ± 7.27 mL·kg⁻¹·min⁻¹) VO2peak (p=0.75). Results suggest that 6MAT VO2 can be used to predict VO2peak among individuals with chronic SCI. The 6MAT should be used as a clinical tool for assessing aerobic capacity when peak exercise testing is not feasible.