Too add to what SSbackwards posted on some GDAs ability to activate AMPk....
PMID: 17292731
"These findings suggest that berberine increases glucose uptake through a mechanism distinct from insulin, and activated adenosine monophosphate-activated protein kinase seems to be involved in the metabolic effect of berberine."
PMID: 16873688
"Strikingly, berberine acutely stimulated AMPK activity in both myotubes and adipocytes in vitro, contributing to enhanced GLUT4 translocation in myotubes and reduced lipid mass in adipocytes"
PMID: 17049164
"berberine-stimulated glucose uptake does not vary as insulin concentration increases... The effects of berberine are not a result of pro-oxidant action, but a consequence of an increased cellular AMP:ATP ratio... These results suggest that berberine circumvents insulin signaling pathways and stimulates glucose uptake through the AMP-AMPK-p38 MAPK pathway"
PMID: 16873688
"Berberine downregulated the expression of genes involved in lipogenesis and upregulated those involved in energy expenditure in adipose tissue and muscle. Berberine treatment resulted in increased AMP-activated protein kinase (AMPK) activity in 3T3-L1 adipocytes and L6 myotubes, increased GLUT4 translocation in L6 cells in a phosphatidylinositol 3' kinase-independent manner, and reduced lipid accumulation in 3T3-L1 adipocytes. These findings suggest that berberine displays beneficial effects in the treatment of diabetes and obesity at least in part via stimulation of AMPK activity"
As you can see I am a big fan of berberine, especially pre-fasted training. Anabolic pump is what I use pre-fasted training. Recompadrol with ALA is what I use prior to my meals.