Regulation of skeletal muscle glycogenolysis during exercise

Publikation: Bidrag til tidsskriftReviewForskningfagfællebedømt

Muscle-glycogen breakdown during exercise is influenced by both local and systemic factors. Contractions per se increase glycogenolysis via a calcium-induced, transient increase in the activity of phosphorylase a, and probably also via increased concentrations of Pi. In fast-twitch muscle, increases in the AMP and IMP levels may increase phosphorylase activity. The rate of muscle-glycogen breakdown during exercise depends on the pre-exercise glycogen concentration and is also influenced by hormones. Insulin may inhibit glycogen breakdown, whereas epinephrine enhances the rate of glycogen use in contracting muscle by increasing the phosphorylase a activity via increased cyclic AMP production. The availability of blood-borne substrates may also influence muscle glycogenolysis and, therefore, exercise performance.

TidsskriftCanadian Journal of Sport Sciences
Udgave nummer4
Sider (fra-til)197-203
Antal sider7
StatusUdgivet - 1988

ID: 154757294