Fig. 4.

Schematic illustrating each of the factors that has been demonstrated to impact upon critical power. Convective and diffusive O₂ delivery act in concert with muscle O₂ utilisation to determine the degree of intracellular metabolic perturbation and fatigue induction incurred during the rest-to-exercise transition. The extent of such metabolic perturbations, in turn, determines whether an exercise bout can be met in a metabolic steady state within a given myocyte. Within a given individual, whether an extant power output is met in a whole-body steady state will depend on the muscle fibre-type composition of the individual, the muscle recruitment patterns employed during the task, and the extent of metabolic derangement and fatigue induction incurred in the recruited fibres during the rest-to-exercise transition. This figure was created with BioRender.com and was exported under a paid subscription. CaO₂ arterial oxygen content, DO₂ muscle diffusive capacity, PO_2im intra-myocyte O₂ pressure, PO_2cap capillary O₂ pressure, $\dot{Q}$, cardiac output