, Concernant la variation de masse grasse, pour les 2 groupes, on a montré des pertes significatives immédiatement après la course de 3,1 % pour le groupe SSR et de 4,1 % pour le groupe MSR. Ces pertes sont retrouvées en phase de récupération jusqu'au 10 ème jour. Les épreuves d'ultra-endurance se caractérisent par une dépense énergétique particulièrement importante et une balance énergétique généralement très négative, pp.34-37

, La filière aérobie correspond à la filière de l'endurance où les efforts sont d'une intensité faible mais d'une durée longue

, Elle permet la synthèse d'un substrat énergétique, l'adénosine triphosphate (ATP), grâce à la dégradation du glucose ou des acides gras (via la bêta-oxydation puis la glycolyse)

, Les substrats principaux utilisés lors d'un exercice prolongé en condition aérobique sont les hydrates de carbone (HCO) et les lipides

, Ces deux chaînes de réactions sont plus longues que la filière anaérobie et développe une puissance plus faible

, L'utilisation des différents substrats dépend de la durée de l'exercice et de l'apport exogène (gel, barre, alimentation) pendant l'exercice (38)

L. Stock-de-lipides-est-potentiellement-inépuisable and . Le-pourcentage-de-masse-grasse, Peu de choses sont connues sur l'équilibre glycémique lors d'efforts de très longues distances en Ultra-Trail. Or ces courses de montagne s'accompagnent de dommages musculaires importants, du relargage de cytokines pro-inflammatoires et d'acides gras libres qui vont diminuer la sensibilité à l'insuline, pp.45-47

, En 2020, l'équipe de recherche de l'UT4M va donc étudier l'évolution du taux de glucose dans le sang pendant différentes courses à l'aide d'un capteur glycémique portatif

, Ceci devrait permettre d'évaluer l'impact de l'alimentation et de l'hydratation sur les performances et la fatigue

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