This article is way out of my league as I don't understand most of it but it seems like not only does metformin lower igf levels but also suppresses muscle hyper trophy and protein syntheses. A buddy of mine said pairing berberine with metformin can negate this issues. He's a science guru so I'll just copy what he said.
The increase in AMPK will inherently suppress muscle hypertrophy in muscle cells (via decreased igf-1 signaling) . You can attenuate this by inducing PGC-1a (happens with intense workouts) but this also suppresses AMPK in these tissues (AMPK will still be active in the liver and fat cells, so those tissue effects would be preserved). Pairing Berberine/Metformin with intense exercise that contracts your muscle cells would be prudent and may reverse the muscle suppressing effects of Berberine/metformin.
And here is the article
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The increase in AMPK will inherently suppress muscle hypertrophy in muscle cells (via decreased igf-1 signaling) . You can attenuate this by inducing PGC-1a (happens with intense workouts) but this also suppresses AMPK in these tissues (AMPK will still be active in the liver and fat cells, so those tissue effects would be preserved). Pairing Berberine/Metformin with intense exercise that contracts your muscle cells would be prudent and may reverse the muscle suppressing effects of Berberine/metformin.
And here is the article
Reproduction | Mobile