Published in:
01-08-2014 | Original Article
Blood lactate and ventilatory thresholds in wheelchair athletes with tetraplegia and paraplegia
Published in: European Journal of Applied Physiology | Issue 8/2014
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Purpose
The purpose of this study was to analyse the influence of spinal cord injury level on blood lactate (BLa) and ventilatory thresholds.
Methods
Ten athletes with tetraplegia (TETRA) and nine athletes with paraplegia (PARA) performed a graded wheelchair propulsion treadmill exercise step test to exhaustion. The aerobic and anaerobic BLa thresholds, the ventilatory threshold and the respiratory compensation point (RCP) were determined.
Results
The BLa thresholds were determined in 34 of 38 cases, ventilatory thresholds and RCPs in 31 of 38 cases. The anaerobic BLa threshold (76 ± 7 % \(\dot{V}{\text{O}}_{{ 2 {\text{peak}}}}\)) and the RCP (77 ± 8 % \(\dot{V}{\text{O}}_{{ 2 {\text{peak}}}}\)) did not differ significantly from each other (P = 0.92), with a coefficient of variation of 4.8 ± 3.4 % between thresholds. All other thresholds differed significantly from each other (P < 0.05). Thresholds expressed as the percentage of peak oxygen uptake did not differ between TETRA and PARA (P > 0.05) despite altered breathing in TETRA, which included a higher ventilatory equivalent for oxygen and a lower tidal volume.
Conclusion
Measuring BLa leads to a higher threshold determination rate compared with ventilatory data and the anaerobic BLa threshold can be used to predict the RCP. The altered breathing in TETRA does not seem to have a pronounced effect on the ventilatory threshold or the RCP.