The effect of manipulating the pre-exercise template on time-trial performance

Abstract

The purpose of this experiment was to understand whether homeostatic disturbances, such as arterial oxygen saturation (SaO2), prior to exercise would reset the pre-exercise template, reflected by the power output (PO) during the first 1 km of a 5 km time trial (TT). Methods: Trained cyclists performed four randomly assigned trials with differing warm up (WU) and TT conditions, including NN, NH, HH, or HN (H-FIO2 = 0.15, N-FIO2 = 0.21) with the first and second letters depicting WU and TT conditions respectively. Results: Using either end-WU HLa, RPE, %SaO2, or a multivariable product now known as the Desaturation Strain Index (DSI=HR*HLa*(100-SaO2), the hypoxic WU was significantly harder than the control (p<0.05). There was no significant difference (p>0.05) between the WU conditions and the PO during the first 500m of the TT. Discussion: The central governor concept suggests that PO might be reduced following a more challenging WU, attributable to hypoxia, on the premise that the exerciser might expect a greater challenge to homeostasis. However, the results demonstrate that despite much more challenging conditions during the hypoxic WU, the PO during the opening part of the TT was not affected, demonstrating the robustness of the pre-exercise template.