Regulation of GLUT4 protein and glycogen synthase during muscle glycogen synthesis after exercise.
Level 5 - mechanism / opinion, no new human data
Narrative review of physiological mechanisms without original empirical data or systematic methodology.
PubMed 9578375 · doi:10.1046/j.1365-201X.1998.0302e.x
What was done
This is a narrative review describing the physiological mechanisms regulating muscle glycogen synthesis following exercise-induced depletion, focusing on the roles of GLUT4 transporter translocation, membrane permeability to glucose, and glycogen synthase activation.
What was found
The abstract reports no numerical data, statistical tests, or effect sizes. It describes a biphasic model of post-exercise glycogen synthesis: an initial rapid, insulin-independent phase mediated by contraction-induced GLUT4 translocation to the plasma membrane and increased glucose-6-phosphate (G6P), followed by a slower insulin-dependent phase characterized by increased muscle insulin sensitivity and potentially increased GLUT4 protein expression.
Why it matters
It outlines the distinct cellular mechanisms separating acute contraction-induced glucose uptake from extended post-exercise insulin sensitization in skeletal muscle.
Limits
The paper is a narrative review containing no original empirical human data in the abstract. No sample sizes, quantitative metrics, or systematic search methodologies are reported.
Cited by
- context Exercise-stimulated GLUT4 transporters remain active and present at the muscle cell surface to facilitate glucose uptake for up to 24 hours.