Good Association Between Sprint Power and Aerobic Peak Power During Asynchronuous Arm-Crank Exercise in People with Spinal Cord Injury

Purpose: To (1) investigate the association between sprint power and aerobic power output (POpeak(GXT)) during a graded peak exercise test (GXT); and (2) validate the prediction models of POpeak(GXT) based on sprint power and personal and lesion characteristics. Materials and methods: Wheelchair users with tetraplegia (N = 35) and paraplegia (N = 58) performed a 30 s-Wingate test and GXT on an asynchronous arm-crank ergometer. Data were split into samples to develop and validate the model. Sprint power (POmean(Wingate) and POpeak(Wingate,) respectively) and POpeak(GXT) were determined. Regression analyses were performed to develop POpeak(GXT) prediction models. Candidate independent variables included POmean(Wingate) or POpeak(Wingate), age (years), sex, body mass (kg) or BMI (kg/m(2)), time since injury (TSI, years) and lesion level (tetraplegia/paraplegia). The best model was validated by comparing the predicted POpeak(GXT) with measured POpeak(GXT). Results: The best model (R-2 = 0.76) to predict POpeak(GXT) included POmean(Wingate), BMI and all other independent variables. No significant difference was found between measured (68 +/- 35 W) and predicted POpeak(GXT) (68 +/- 30 W, p = 0.97). The ICC was excellent (0.89 with 95% confidence intervals: 0.75-0.95). The 95% limits of agreement for the Bland-Altman plots were wide (-30 to 31 W). Conclusions: Strong associations were found between POmean(Wingate) and POpeak(GXT.) Although relative agreement was excellent, absolute agreement was low.