“You can sort of lose the ability to use fat, you can sort of lose the ability to use carbohydrates, you can up-regulate both ends of the spectrum, you can control how fast you’re switching back and forth.”
“The main fuels are going to be fats and carbohydrates. And with metabolic flexibility, there’s just three components. So on kind of the right end of the spectrum, how well you can use carbohydrates. On the left end of the spectrum, how well you can use fat. And the third component is how well can you switch back and forth between those two.”
“So if you’re doing some heavy weight training, it’s to your best advantage to try to use as many carbohydrates as you can. Because the advantage carbohydrates have is you can create ATP, so cellular energy, at a much faster rate because you need energy and you need it in a very short time period. On the other end, when you’re using fat per basically unit of energy, you get way more ATP from fat than you do carbohydrates. The downside though is that it takes you longer to liberate all that ATP. So it takes you much longer timeframe to do it. So when we’re sitting here having this conversation, like fat is a much more preferred fuel source because there is no rate limit. We don’t need to get energy really fast. The muscles are really not doing a whole lot.”
“You can change how well your body uses fat. You can change how well it uses carbohydrates. So for example, if you do a ketogenic diet. So a ketogenic diet is very low carbohydrate… Because you’re running so much fat through the system, insulin is also very low. You will upregulate your body’s use of fat as a fuel. However, the cost with that is, you will down regulate your body’s on the high end ability to use carbohydrates. So if you’re a speed and power athlete, it’ll probably cost you 8, 10, 12 % right off your top end of speed and power.”
“My little running joke is that physiology is full of every bad engineering word. It’s anisotropic, it’s chaotic, it’s nonlinear. To, to run a lot of mental models to figure it out, it just rarely ever maps that way. However, if you still look at output and you still look at what is the system capable of doing, at least then you know if you’re going in the right direction or not. If you’re not going in the right direction, okay, then we’ll take a systematic point of view and we’re gonna get deeper and deeper all the way.”
“On the carbohydrate in the spectrum, I have what I call the two pop tart test. For breakfast, can you have two pop tarts, nothing else, and how do you feel for the next couple hours? If you wanna crawl under your table and take an insulin-induced nap, I would make a hard argument that you’re probably not very good at using carbs.”
“On the other end of the spectrum, for fat use, we know that the lower you push insulin levels, that will push your body to use more fat. So how would you get low levels of insulin in a safe manner? Just don’t eat. I would argue if you can do a fast for 19 to 24 hours, know, consume some fluid, consume some electrolytes. Yes, you’re probably gonna be hungry. But if you can do that and relatively function and train and do everything you could normally, I would argue you’re probably pretty good at using fat as a fuel.”
“Some people with just sky-high glucose… Their body’s having a hard time using glucose. They can’t dispose of it in the tissue. So it’s sort of backing up in the bloodstream. They can’t stick it into glycogen. They can’t put it in liver glycogen. They can’t use a process called de novo lipogenesis, convert it into fat, stuff it somewhere else.”
“Some people with sky-high glucose, their insulin was elevated but not too bad. Other people who had moderate glucose which again in this study was like, you know 110 125 it’s still elevated for sure a couple of those people had absolutely sky-high insulin and so I would argue that those people are much farther down the progression, right? Because their body is saying, ⁓ we don’t want this high level of glucose hanging out in the bloodstream. So we’re going to put out more insulin to try to get it out. Oops, that didn’t work because a lot of the tissues are insulin sensitive. So we’re going to put out more insulin and more insulin and more insulin. And eventually at some point, even maxing out insulin isn’t solving the issue that they’re seeing.”
“Insulin is one of the main signals to try to get it the hell out of the bloodstream. Insulin is like a fuel selector switch. So high levels of insulin will actually push you to use more carbohydrates, right? Because if we have more muscle movement, we’ve got more glut4 translocation, non-insulin mediated uptake, all this kind of stuff. Muscle doing things to suck up more glucose will solve the issue. Which is why for even like type two diabetics and just general metabolic health, shocker, movement, exercise, training, lifting heavy stuff, walking, all those things are so beneficial because that allows muscle to one, be more sensitive to glucose and then two, acutely pull that glucose out and start using it as a fuel or potentially store it.”
“Your body is wired to not go hypoglycemic at all costs. Your body can live for a while in an elevated state of high glucose. Yes, eventually will that glycate some of your tissue and increase AGEs and mess up your tendons and your muscle and all that stuff? Absolutely. But that’s a longer term problem. Acutely, if your blood glucose just plummets super low, you’re dead, right? So most of all, the counter regulatory mechanisms in the body are designed to prevent you from going too low. So things like stress response, cortisol response, your epinephrine, norepinephrine, all those things are designed to try to prevent you from going a little bit too low. And the good part is, in someone who’s functioning healthy, it’s really, really hard to make a healthy person hypoglycemic. But you start getting those systems to be dysregulated, you start getting into disease, type 2 diabetics, et cetera, you can become more dysregulated, and you can, unfortunately, see these really big lows that are very dangerous.”
“We do know for sure, by looking at diabetics, that their risk of tendon stuff definitely goes up… the more uncontrolled they are, the higher blood glucose they have, the worse it’s probably gonna be… I don’t really have any time course on it. It’s probably months to years and probably not weeks.”
“If we look at high level endurance athletes who are running marathons, elite level athletes, they’re pretty much always running using carbohydrates. They’re not worried about, oh, let’s go low carb, right? They’re worried about performance at all costs. You could argue that health may not be their number one thing either. I have seen data from high level marathon and half marathon people on a metabolic heart that they literally had no crossover period. Meaning at no point during the entire test did they get to even 50 % of fat use, even at super low intensities. So super low intensities you should hit 70, 80, 90 % fat use. Now they were competitive, they were pretty highly ranked, I can make an argument from a health standpoint, because they’ve lost metabolic flexibility that it may not be the best for their long-term health. Again, exercise itself is incredibly protective. So could they do that approach for probably a few years and be fine? Yes.”
“I’ve had athletes on four or 500, 550 grams of carbs per day, like not even a carb cycling approach… Their bloods are all good. Everything is fine. Now again, they’re doing a lot of exercise, they’re eating mostly whole foods, so they’re doing a lot of things. I don’t think you can take the average American whose butt looks like a couch cushion and dump 500 grams of carbs in him and expect them to have that turn out real well. It’s probably not gonna turn out well.”
“If you have a high background of carbohydrates, It does tend to push you a little bit more at rest to probably carbohydrate use but the minute we stimulated the system just a little bit with a low amount of work, they would normalize.”
“If you can’t down regulate to use fat and you’re stuck on that high carbohydrate in the spectrum, just sitting there talking to us. We’re like, whoa, like they’re burning so many carbs, they’re spinning off lactate at rest. Of course they’re generally a metabolic wreck like, I can’t do any exercise or output is bad, their sleep is bad. They’re so sympathetic that they’re just running on carbs all the time. And one of the hallmarks of those people is that they have to eat with a really high frequency. Like fasting is virtually impossible for them to do. And I think it’s because they can’t down regulate to use fat as a fuel very well. So there are a lot of those people out there. Some of them are even high level athletes who just, you know, were overreached, over trained, you know, things of that nature too.”
Obesity: “The leaner people generally were more metabolically flexible. Now again, could you find individuals in that population given enough people that that is not true? Yes, I’ve ran into those people and tested them myself. But in general, obesity just tends to throw a monkey wrench in everything. So we talked a lot about insulin dynamics and all that stuff, but what my Ben House says, which I like, that Calories are just kind of your trump card, meaning that all of the things being equal, if someone is in a massive caloric excess, and especially if they’re not running energy through the system, right? They’re just not moving a lot. Literally, you could pick a system and it tends to go in the wrong direction.”
“Could you be fat but also fit? And if you look at that data long enough, the longer someone stays, air quote, fit, but is getting heavier and heavier, at some point, two, three, four, five years into it, they almost always have metabolic issues. Now again, could you do enough exercise to potentially offset that? I think you can. You can look at studies in sumo wrestlers and some other athletes, but those are edge cases that are doing massive amounts of exercise and energy output. So the takeaway I would say is, if you’re at a higher flux rate, you’re just moving more energy through the system that is incredibly protective, independent of body fat and body weight. However, at some point that’s probably gonna catch up with you and most people are not gonna do enough exercise to counteract that. At some point, if you do get heavy enough, especially if that’s more body fat and you have less muscle, that’s gonna catch up with you and pretty much any system you look at that at some point is gonna be going in the wrong direction.”
GLPs: “If you would have come to me like five years ago and say hey, man Do you know in five years we’re gonna have these drugs? They’re so effective that people are gonna be crushing their appetite so much that they’re gonna be chronically under eating, they’re not going have enough protein. They’re going be losing lean body mass, and they’re just going to be dropping weight like crazy. I’d have been like, what are you talking about? That’s never going to happen in my lifetime. You’re insane. That is never going to happen. know, hunger, appetite, all of those are multifactorial, redundant, survival-based mechanisms. And I was wrong. That’s what we have. Like, you could argue the lean body mass loss with some of the trials of GLP-1s. Granted, most of these people are not exercising, they’re not lifting heavy ass weights, they’re probably consuming too little of protein.”
“My fear though is that GLP-1s will be the same as TRT. Like once people go on, I don’t think they’re ever going to go off.”
“To me, a carnivore diet is kind of the end of the road of an elimination diet. So I’ve had clients and people do it as just a way of, okay, let’s just do a reset. Let’s just pull out as much stuff as we possibly can. Get your gut fixed, maybe get your inflammation down, get your body cooperating again, and then we’ll, at some point, we’ll slowly reintroduce things at another point.”
“There’s a debate in the tendon world about tendinosis versus tendonitis. In general, tendinosis is more the collagen gets scrambled, the soft tissue’s all goofy. Tendonitis is more of an inflammation type response. So I do kind of use that with clients to try to give me an idea of, okay, am I going to have more target isometrics, maybe some eccentric, some collagen, some things that try to change the architecture, or is there overall diet just a disaster and it seems to be more tendonitis and we’re going to go more after inflammation. We may try things like, you know, curcumin, high dose fish oil, like I have official tests we give them. So poke your finger, bleed on this people paper, send it in. It’ll run every lipid in your body. They’ll tell us EPA, DHA, red blood cell content, all this kind of stuff. We’ll do that. And then just clean up your diet, eat more micronutrition. Maybe we could play with some fasting if you can tolerate it or not. At the end of all of that, maybe we end up doing a carnivore diet. Like if we keep pulling stuff out and we find that, okay, this fiber wasn’t good or it’s low FODMAPs or lactose or common offenders gluten, etc. So That would be my guess, you know, and again, I’ve seen blood work from people doing carnivore that looks amazing.”
“Caveat with keto, I’ve seen a few people where their blood lipids go absolutely completely squirrely off the chart. I would say that’s not the norm, but every once in a while there are people who just, they don’t seem to handle, you know, high fat very well. You can argue about maybe it’s a genetic thing, maybe they have hypercholesterolemia, things like that. So I would say to anyone making any dietary change, talk to your doc or if you want to run blood work on yourself and look at it for performance metrics, get some baseline blood work, do the thing you’re going to do, and then at least just get basic lipid panel, ⁓ CBC, CMP, 90 days later, 60 days later, just to get an idea.”
“So pretty much anyone who has a statin, that’s the first question I’m going to ask them. Go back to your doc, ask him if it’s okay if you can take Coenzyme Q10. There’s a debate, do you use Ubiquinol or Ubiquinone? The ones that reduce form or not. I don’t know. I don’t even know if it matters much at this point. I’ve gone back and forth on that probably a dozen times and just take some. I think you’ll probably be better.”
“I’ve tried to look at anything that would accelerate soft tissue healing or adaptations. The only things I’ve come up with are, yes, I metabolic health is a big part of it. To what degree? I don’t know. Just be metabolically healthy. Don’t have high glucose. Make sure your insulin isn’t rind. Make sure most of your blood panels all look good. Outside of that, I haven’t found anything that would accelerate it unless it’s accelerating your ability to train more frequent.”
BPC-157: “I’m still on the fence about it. I’ve had clients play with it through a physician since 2018. And I would say 60 % were like, Oh my God, this is the greatest thing you’ve ever had me do. And 40 % were like, I couldn’t notice any difference whatsoever. Same peptides, same protocol, same doc. Again, all used for different issues and different pathologies, so who knows.”
“If you’re looking at hypertrophy of tissues altogether, I’ve often wondered if bone stimulation is the rate limiter. Meaning if you can get a heavy enough stimulus to activate the piezoelectric effect in bone, does that have downstream effects that’s automatically going to hit muscle and tendon? I don’t know. That’s just something I pulled out of my ass, but it’s something I wonder.”
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