ETAPA 2 IDENTIFICACIÓN DE ACTIVOS INTANGIBLES

The adopted metabolomics approach enabled the distinction of plasma samples obtained at the point of fatigue (post-fatigue) from samples obtained prior to and following fatigue. The specific metabolites contributing to this distinct profile were then explored. In accordance with our hypothesis, FFA and TRP played influential roles in contributing to these distinct metabolic profiles and in so doing, lent support to the ‘Central Fatigue Hypothesis’.

Additionally, the 87 identified metabolites which demonstrated significant changes over time generated potentially interesting avenues for future investigation, including, for example, some novel roles for FFA in exercise-induced fatigue onset. It is important to note that while the approach adopted herein was able to capture a large number of metabolites within the plasma samples, not every metabolite was captured and identified. Moreover, it is important to note that a change in the concentration of metabolites across time-points, and in particularly a change in the concentration of intermediary metabolites, does not provide information on the rate of appearance or disappearance of metabolites within a pathway (i.e., metabolic flux). Nevertheless, despite the relatively short time-frame between sampling points in the current study, the metabolic profile of plasma demonstrated a significant shift during and after exercise and included a distinct metabolic profile at the point of fatigue.

3.8

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Chapter 4

Neuromuscular fatigue