The verification phase and reliability of physiological parameters in peak testing of elite wheelchair athletes

The purpose of this study was (1) to examine the value of a verification phase (VER) in a peak testing protocol and (2) to assess the reliability of peak physiological variables in wheelchair athletes. On two separate days, eight tetraplegic (TETRA), eight paraplegic (PARA) and eight non-spinal cord-injured (NON-SCI) athletes performed treadmill ergometry, consisting of a graded exercise test to exhaustion (GXT) followed by a VER. Peak oxygen uptake _V O2peak was compared (1) between GXT and VER and (2) between test days. _V O2peak did not differ between GXT and VER (P = 0.27), and coefficients of variation between GXT and VER were in the range of 2.9 and 6.4 % for all subgroups. Coefficients of variation of _V O2peak between test days were 9.3 % (TETRA), 4.5 % (PARA) and 3.3 % (NON-SCI). It is therefore concluded that whilst a VER can be used for a more robust determination of _V O2peak, a deviation of up to *6 % between GXT and VER should be considered as acceptable. For between-day analyses, relatively large changes in _V O2peak are required to confirm ‘‘true’’ differences, especially in TETRA athletes. This may be due to their lower aerobic capacity, which results in a larger relative variation compared with the other subgroups.