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. 2011 May 15;589(Pt 10):2443-5.
doi: 10.1113/jphysiol.2011.209346.

The power-duration relationship of high-intensity exercise: from mathematical parameters to physiological mechanisms

Scott R Murgatroyd  1 , Lindsey A Wylde
Affiliations

The power-duration relationship of high-intensity exercise: from mathematical parameters to physiological mechanisms

Scott R Murgatroyd et al. J Physiol. .
No abstract available

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Figures

Figure 1
Figure 1. A schematic representation of the putative physiological events represented by W′ during high-intensity exercise above CP
This ‘fatigue cascade’ continues to develop throughout supra-CP exercise to induce intolerance shortly after the attainment of formula image. Specifically, depletion of finite energy stores (1) (originally proposed as physiological equivalents of W′) leads to the accumulation of metabolites implicated in skeletal muscle fatigue (2) via challenges to cellular homeostasis (3). Consequently, to maintain constant-work rate exercise, recruitment of additional muscle fibres is necessary (4). Whether this leads directly to the increased energy and oxygen costs of the exercise (5) (reflected in the formula image slow component, formula image), or whether the fatigue itself reduces efficiency directly, or both occur, remains equivocal. This cycle continues until the attainment of formula image at which point (or soon thereafter) intolerance ensues. Whether exercise intolerance is a direct consequence of attaining formula image itself, the accelerated depletion of the residual energy stores or the perception of these events, also remains to be resolved. Continuous and dotted arrows denote demonstrated and hypothesised links, respectively.
See this image and copyright information in PMC

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