Abstract
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.
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
.
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).
Strong associations were found between POmean
Wingate
and POpeak
GXT.
Although relative agreement was excellent, absolute agreement was low.
Implications for rehabilitation
There is a strong relationship between peak aerobic power output and sprint power output, both tested on an arm-crank ergometer, in people with spinal cord injury.
A prediction model for peak aerobic power output, based on sprint power output and personal and lesion characteristics, showed a high explained variance.
The predictive model can give a guideline for choosing the right graded exercise test protocol but should be used with caution.
