Can a 15m-overground wheelchair sprint be used to assess wheelchair-specific anaerobic work capacity?

Objective: To evaluate whether outcomes based on stopwatch time and power output (PO) over a 15m-overground wheelchair sprint test can be used to assess wheelchair-specific anaerobic work capacity, by studying their relationship with outcomes on a Wingate-based 30s-wheelchair ergometer sprint (WAnT).

Methods: Able-bodied persons (N=19, 10 men, aged 18-26 y) performed a 15m overground sprint test in an instrumented wheelchair and a WAnT. 15m-outcomes were based on stopwatch time (time and mean velocity over 15m) and on PO (primary outcome: highest mean unilateral PO over successive 5s-intervals (P5-15m)). WAnT-outcomes were mean unilateral PO over 30s and the highest mean unilateral PO over successive 5s-intervals. Correlation coefficients (Pearson's r) and coefficients of determination (R(2)) were calculated between 15m-sprint outcomes and WAnT-outcomes.

Results: Time over 15m (7.2s (± 1.0)) was weakly related to WAnT-outcomes (r=-0.61 and -0.60, R(2)=0.38 and 0.36, p<0.01), similar to mean velocity over 15m (2.1 m·s(-1) (± 0.3), R(2)=0.43 and 0.39, p<0.01). P5-15m (38.1W (± 14.0)) showed a moderate relationship to WAnT-outcomes (r=0.77 and 0.75, R(2)=0.59 and 0.56, p<0.001).

Conclusions: It seems that outcomes based on stopwatch time over a 15m-overground sprint cannot be used to assess wheelchair-specific anaerobic work capacity, in contrast to an outcome based on PO (P5-15m). The 15m-sprint with an instrumented wheel can be implemented in rehabilitation practice and research settings when WAnT equipment is not available, although care is needed when interpreting P5-15m as an outcome of anaerobic work capacity given that it seems more skill-dependent than the WAnT.