Peter Attia is experimenting with metformin's impact on exercise performance using resting lactate and lactate performance curves.

“the question is does that difference matter clinically and is it possible that metformin is actually not helping in the context of exercise are you seeing that in the presence of metformin if you are exercising you're producing less Lak theater I'm seeing more lactate in the presence of metformin”

“I mean that's a plausible how are you measuring your lactate using blood in the finger yeah we should do metabolomics on you I mean with our new instrumentation we can measure not just lactate but literally measure every hundreds of new blades it gives a little bit more of a comprehensive snapshot of all of your metabolic to please could we get an IRB to do that easily let's do it I'm doing it all in so we could do it we could do an on metformin off metformin snapshot because so here's my crude thinking on this is if metformin is inhibiting complex one it wouldn't be beyond the realm of possibility that the body might preferentially not shuttle pyruvate into the mitochondria I mean it's still doing so to a great extent but if it's disproportionately keeping pyruvate outside and turning it into lactate that could drive up lactate levels the thing that surprised me the most is how high my resting lactate levels seemed to be I mean I remember before I started taking metformin you would barely check a resting lactate level but it was usually below 1 millimolar now my resting lactate level on metformin is typically between 1 and 2 millimolar it's about 2 X”

“the one area that I'm most interested in this question is what is the impact of metformin on the ability of exercise to improve the phenotype and that's something that just on a personal level I've been experimenting with a lot so doing a lot of lactate testing on myself with and without metformin and using lactate as a proxy for mitochondrial function”

“I need to find the right time to take it and before I was taking it when my stomach felt in good shape and you can tell when your stomach feels out of whack either you've eaten a big meal the night before or you're just not feeling right a little bit of heartburn out of those cases I don't take me for me because it does a number on my stomach which is great if you don't want to eat but also I'd prefer not to always have a a sore stomach so I was already timing it so now I just take me Foreman went on I know I'm going on a long trip and I'm not gonna sighs you know I'm on planes and trains that's a good time to rebuild your body and then if I'm at home and I'm exercising a couple times a week I'll lay off the mat for me”

“So then I lowered it to a nighttime dose of one gram. I still didn't really see much of a difference.”

“So I think the first change I made was I just stopped taking a gram in the morning and increased my nighttime dose to 1500 milligrams. So I reduced my overall dose by 25%, but shifted it to the nighttime thinking, well, I should have a lower concentration in my bloodstream in the morning. I saw no meaningful effect.”

“So I reduced my overall dose by 25%, but shifted it to the nighttime thinking, well, I should have a lower concentration in my bloodstream in the morning. I saw no meaningful effect.”

“in 2018 i started to very very closely track my lactate levels during exercise and in particular i was tracking my lactate levels during a type of exercise called zone 2 exercise which is when you're basically trying to see how much work you can do under purely aerobic conditions the definition of this is is actually how much work you can do while keeping lactate below 2 millimole i used to do”