Episode #376: Cycle Syncing, Cardio Myths, and Iron Deficiency: A Barbell Medicine Review of Diary of a CEO's Viral Claims

28:30That's a workout. And I'm like, if that's the takeaway, you just missed this opportunity to possibly affect millions of people's lives and you confuse them. Polarized, pyramid, which type – like, come on, bro. I think we also – part of the discussion was that everybody should be lifting weights. Everyone on the panel agreed that you should be lifting weights. And when we talk about lifting weights, we don't use any kind of heart rate zones. Like that's not that's not language that we're using in the lifting space. So, however, there is such thing as high intensity or high load resistance training.

29:11So where does that fit into this recommendation? Because we're supposed to be lifting weights, but we're not allowed to do high intensity interval. Is that only sprinting that we can't do every day? And how do we? So if you're going to say I'm speaking to all women in general and we need to be lifting weights heavy, right? High load training. And then we also need sprint interval training. But we need to be very careful about the frequency at which we perform either of these things with no discussion for total volume. What's my training program? Yeah, exactly. Yeah. You can't do anything. It's like a, it's like you have like a low carb or a low fat or a low fat person.

29:54They're both debating at the end. They come to some agreement. It's like, so what do I eat now? And they're like, I don't know. Can't eat anything. Can't eat anything. Drink water. It was also weird. She got the zones wrong also. Yeah. She's like zone one where it's sitting around. And I'm like, so no. I mean, there are multiple different models for exercise intensity, three zone, five zone, seven zone that you alluded to earlier. Zone one is like the start of exercise. Just it's definitively exercise. Most places, if it's Siler's original work or whatever, it's like 50 percent of your VO2 max is like the start of zone one.

30:29It might be like 50, 55 percent of your max heart rate, maybe 60 percent, depending on who you read. It's not sitting around. And if you even want to go to like the physical activity guidelines, all right, it's got to be greater than than, you know, three METs, four METs. Well, one MET is sitting around. So it's got to be – it's not sitting around. And then she says zone two is the bro science kind of thing. If we're going to loosely define bro science, it's a recommendation that isn't supported by the real science, right? Yeah, totally. So it's like what you see in the gym and then you tell your bros and then you guys are doing this program that's probably fine.

31:08But, you know, so like you're doing it for a reason that makes no sense and that's bro science. Yeah. Of all the evidence we have on exercise, like zone two, are you saying zone two is bad or it doesn't exist or that there's like, do you think she was thinking of Huberman when she said it? Like she was like, she just bros, like just right to Huberman, like that image popped in her head. Or Atiyah, I guess he likes zone two. Yeah. Love zone two. Yeah. Yeah. I don't think zone two is like this specialized exercise intensity for conditioning that you have to do it to maximize your health benefits from exercise.

31:48It's a fine training intensity to use. And, you know, to Atiyah's and, you know, to a lesser extent, Huberman's point or people who talk about zone two, the good part about it is you can do a lot of it without it, you know, blowing you up. It's just not very fatiguing. That said, if somebody's only doing, you know, an hour and a half, two hours a week of conditioning, I say only because you're not quite getting to the physical activity guideline minimums there yet, but we're just decidedly not talking about endurance athletes. You don't have to do zone two to prevent being over fatigued. In fact, I suggest probably a little higher intensity because you're not doing enough volume at that point.

32:22And so you could probably get a little benefit if it was a little harder. But yeah, bro science, if you just decided to like define it as most people do, like just some thing, it's not optimal, not really evidence-based. It's not the reason why you're doing it or saying it doesn't really make sense, but you do it anyway. And it's like maybe with gym rats. Sure. I don't know that zone two qualifies as that. Like it doesn't mean. I think if what would have been a much better message is, again, clarify who we're talking to. What's your goal? Because if your goal is to run a marathon, you're probably going to do a lot of zone two, right?

32:56Because your goal is run far. Yeah. And you can't sprint a marathon. So we're going to need some zone two in there. Now, if you're just starting out with exercise, maybe zone two is a good place to start because if we're going on a run, then we want to make sure our running mechanics are good before we start sprinting. With the caveat that you can do moderate or high intensity training using a variety of modalities. And I would say for somebody who's new to exercise, running wouldn't be my pick. All that is to say we're identifying an audience, we're identifying a goal, and then identifying the strategy.

33:42And so the strategy would be, am I using a stationary bike? Or am I going for a run? Or am I using a rowing machine? And then do I prefer to do something at a lower intensity for a longer period of time? Or do I want that time efficiency and I'm going to get those intervals, you know, done so I can move on to the rest of my day or to the other part of my workout? I think any personal trainer would tell you this. So, like, we're having this conversation that seems so obvious, like we need goal-oriented training that's going to help people move more in a way that they will do consistently and it'll be good for their health.

34:22or we're going to really optimize all of these things for this athlete for their performance. Like, why are we missing all of that very, very obvious context when you're spreading this message to millions of people who 75 % of whom aren't exercising? Right. Yeah, it is interesting. It's like it makes me think that she doesn't coach people or like it has not coached people for a while or like interacted with with people in this way. Because, as you know, when you when you in a professional sense, if you're in the clinic, if you're in research or whatever, you end up developing ways to communicate effectively to others, wherever your niche or profession lies.

35:07And so, you know, I can tell in this podcast, the physicians, for example, when they are hard in the medicine, talking about anemia, for example, or like, you know, very things that are not really super related to the wellness industry. So, you know, leaving aside hormone replacement therapy, leaving aside exercise, leaving aside nutrition, the medicine stuff, they're pretty good. And we'll have Dr. Austin Baraki like talking about the ferritin thing, but pretty good because these are things they actually talk with their patients about regularly. And it's very central to their training, right, how they were educated and they got to stay up on it because it's important.

35:47But when they start going away from that, things they don't actually do regularly talk about exercise and, you know, maybe they are having these conversations about exercise, but there's certainly outside the area of expertise. Things get weird. They get real weird. And you'll notice in this entire, they got five and a half hours of this podcast, right? Edited. So it was probably longer. That's what I'm saying. At no point do they run through, here are the exercise variables, frequency, intensity, time, type, volume, progression. Here's how we would manipulate, you know, and here's what we mean by intensity.

36:18Here's what we mean by volume, you know, whatever, none of that stuff. And I'm like, so you don't actually just talk about exercise programming, exercise prescription regularly with people. I don't think you do it very often. And then when you do talk about it, you get very basic definitions wrong. Zone one is sitting around. And so to me, all of this says is like, I just don't think you do this on a regular basis, which calls into question like, why are we going to you as the expert? But before we go down that tangent, hold on, I got something for you. Dr. Vonda Wright then after this starts taking digs on classes.

36:50She's like, these people are doing this Ignite class and it's moderate intensity. And so apparently she agrees that polarized training is good and you should avoid this moderate intensity, although nobody defines what that is, especially in the case of like a circuit training class because this is lifting weights and not cardio. But anyway, she says you need high intensity for change, but there's a risk of injury up there. So then you need low intensity for recovery and sprint interval training recomposes the body. So she's talking about weight loss, body recomposition. Yeah. What's your take on Dr.

37:23Vonderreit here? You know, I mean, I think we can have a broader discussion on on why it's important to stay in your lane, because for some reason, when when people when anyone writes a book, it's like the publisher insists that they include an exercise and a nutrition chapter, even though they are not an exercise or a nutrition person. And I guess that means because they sell more books that way. But you end up with these insane recommendations that are somehow novel. And so her thing is going to be, you know, that we have to do all this jumping. But when we think about, again, the exercise we're doing and the goal, which we always have to go back to, right?

38:04Is it weight loss or are we just training for overall health? Because I thought we were just saying these are broad exercise recommendations for women. And now she's throwing weight loss or body recomposition in there. And we very clearly know that in order for us to gain muscle, we want to recommend resistance training because sprinting, maybe if you've never done any exercise at all and you do a little bit of sprinting, you'll gain a little bit of muscle and then that's it. So this is not a good recommendation for muscle growth. And when we have a conversation about weight loss related goals, we need to address how many calories you're eating.

38:43We need to address the diet. Because when we start engaging in an exercise program, we typically start to eat a little bit more. And then we have potentially some reduction of NEAT. And then we end up just not losing the amount of weight we would anticipate from or calculate from this energy that we're expending during exercise. and we don't you don't have to put that in right you we didn't have to put that whole explanation in there that's fine but i would have preferred the message be we should all be exercising for you know for overall health but if the goal is muscle growth and that should be one of the goals we need to lift weights and it needs to be challenging and etc um if the goal is to lose body fat then we're probably going to need to address that with the diet Sprint interval training, recomposing the body, meaning you're going to gain muscle and lose fat.

39:47Is it's a highly inefficient, inefficient recommendation for somebody with that goal. Yeah. Yeah. And ultimately not likely to be successful even in the moderate term and certainly not the long term. It's just modest changes, particularly if you're untrained initially, but then long term, like. I mean, just exercise, generally speaking, pretty modest effects on weight management overall. Body composition, certainly with resistance training, definitely improved, can prevent weight regain. And there's a lot of also obviously weight independent benefits that we should probably be celebrating rather than just weight management.

40:26But in the context of just like weight loss, body fat loss, whatever, like most people would not look, would see the results from exercise, generally speaking, and say, that's not very compelling. a very compelling reason to exercise. I'm like, yes, I agree. I agree. The diet is something that we should people to people don't understand this. A lot of people don't understand this because they do exercise for weight loss. And as you said, they are kind of disappointed because it feels like I'm not I'm working hard. I'm doing the thing and I'm not getting the results. Why not? And so and we can explain the metabolic adaptation or why, you know, just expending energy doesn't necessarily equal weight loss, even if you're counting all the calories and adjusting.

41:13But the general message is we want to make recommendations that are as helpful as possible for people to reach their goals and feel successful because then they'll stick with it. Otherwise, they'll just give up because they'll feel like, well, I'm working hard and this isn't even doing anything for me. Well, that's why we need to explain if weight loss is the goal, then we need to address the diet and you should be exercising for this host of other reasons. And so if people understand that, then you're setting yourself up for some realistic expectations. And that's doing people a favor to honestly communicate that.

41:54And maybe she doesn't know. I think probably she genuinely doesn't know, in which case she shouldn't be talking about it. Well, that's that's the whole thing. Right. It's like, again, when when these the the women on the panel are in their definitive area of expertise and I'm taking Stacey Sims out of this equation because I'm actually I'm actually not sure. area. Yeah, exactly. But the other women physicians who have training, board certified, when you put them right in their niche, generally they do a reasonable job, not only at getting the science right, but also in communicating that in a way that is accessible, because again, they do this on a regular basis, right?

42:36When they get outside of that area, not only is the science wrong, but the way that they're trying to communicate it, it falls apart because they don't do this regularly, right? They're not having these conversations with patients. And if they are,

42:50Lord help them. I don't, I don't know what to say. Yeah. It's just, it's just really bad. I genuinely did not hear any good advice about exercise in the entire podcast. That was not very generic. Like women should lift weights. And I'm like, yep, we agree. Yeah. And I'm like, okay, but, but what about like how, okay, so let's, let's rate this. Let's give this some bowls here. All right. So this is our exercise section conditioning specific. I'm going to give this five bowls on the BS meter, mainly because like at every step of the way, it's just wrong. Like just definitions are wrong. The way that you're talking about prescription is wrong.

43:27That stuff you're leaving out is important. So that's also wrong. You agree if it's a five out a five on the BS scale. I agree. And I'm going at least a 4.5, if not a five on the harm, because when we think about overly complicated recommendations where we don't even understand why we're doing the thing that we're supposed to be doing or how to execute this recommendation, this is putting up another barrier for people who aren't exercising to just start doing something. And I wish people who have go on these big platforms, you know, you have hours just to convey a message. Why can't we say for the majority of people, we need to find something that we will do consistently week in and week out for years to come.

44:21That's, you know, one of the best things you can do for your health. Let's just all say it. Yeah. Yeah. Just lead with that. Lead with that. Yeah. Yeah. I think if you if you factor in like opportunity cost, like the time that they spent talking about stuff that is either wrong or definitively does not matter. Right. And it's not actually helpful. Then, yeah, maybe five, five or six out of five on this on the harm scale. Yeah. You had an opportunity. You fumbled and then further added in a bunch of stuff that was incorrect. And so if somebody were to take this information, they would do, I guess, only some sprint intervals.

45:00Apparently four is the number, according to Dr. Sims. They would lift weights, but unclear how or how often. But they would not do any moderate intensity, continuous conditioning. They would not do any low intensity steady state because, again, you know, you don't need to do that. You're just sitting around that zone one. So you don't need to you don't need to do anything. It's just sit around a little bit. That's so in one. So and then on top of that, if you added that with the cycle syncing, then they would, you know, just do less. So under training, just sprint intervals, plus weightlifting.

45:37Like I'm here for the weightlifting, I guess. I just would be curious as to what that prescription would actually look like because that never happened in the entire five and a half whatever hours. and they never talk about like uh so in general like here's how many days per week you should be lifting here's how many you know exercise you should pick it like just any sort of organization right about that whereas i would say look you should be lifting at least two days a week should all the major muscle groups of the body for a couple sets that feel kind of hard yeah i i find that it made it harder to listen to as well because there was so much bouncing around and And so it wasn't like, OK, let's talk about lifting weights and then, you know, we're going to start here and talk about it for 10 minutes or 20 minutes or however long we need to talk about it and then kind of put a button on it for the listener and say, here's the takeaways and then move on to the next topic.

46:27Instead, it was just kind of bouncing back and forth between the discussions about hormones and then the discussions about exercise, which overlapped with are we lifting for general health or do we have these endurance goals or do we care about muscle but then what about hormones and then bone and it was was very very difficult to follow and I don't know if we can blame the guests necessarily for that because they're not responsible for how the show was organized but I do think if you're communicating something as important as exercise then it is on you to frame it in a way that people understand what am I doing and why am I doing it?

47:15Yep. Yep. I agree. It was very challenging to follow this. Finally, we want to address a medical topic that came up, anemia and iron deficiency. Now, the guests on the episode discussed how the norms of ferritin have changed and suggested that the medical establishment is accepting sicker populations as normal. So I called in Dr. Austin Baraki to weigh in on this topic. Let's hear from him. Hey, I'm Dr. Austin Baraki, and I'm happy to be joining this breakdown of the recent Diary of a CEO conversation. The clip you're about to see focuses on women's iron status and iron deficiency, which is extremely important in women's health.

47:52So let's watch the clip, and then I'll provide a response. Anemic, with iron deficiency being the leading cause. You notice the norms have changed? So it depends on who you read. Yeah. Again, you know, when you're looking at male normative curves versus what, you know, we tend to accept lower levels for a female. But now that we're looking at performance and, you know, looking at other factors besides just what is this ferritin level, there's a lot of great new research coming out that we are looking at this differently. And that we're in our clinic, we are looking for 60 to 100 for a ferritin level to be considered optimal.

48:32Very different than, you know, the baseline for, you know, keeping you out of a hospital versus you functioning at your absolute best. Yeah, because the norms that often get measured for us. Because they tripled, right? They were 15 and then they went up to 40. So now they're saying 20 and above is normal. And when I look at a lot of women who are sitting 20 to 30, they can't get help. It cannot get help. And it's like, whoa, it was maybe four or five years ago. If you were below 50, then we would look to get help. But now with the norms that have shifted with the sicker population, we can't get women help unless they are below 20.

49:17So when we say normal, I think this is important for everybody watching or listening. Normal in medicine means common, not non-pathological. Okay. Not bad. You know, it doesn't mean it's not bad. And so norms shifting, meaning we're getting sicker as a population, and we're willing to accept lower levels, although they're not optimal for health. The lab reference range, what they say when you get your blood work drawn and you see the reference range, is based on population averages. And so if the population is more anemic, this is going to accept lower levels being normal, even though they're by no means optimal.

49:57And I think that's one thing we all talk about is, well, how are you feeling? Your symptomology, what do we see? And you have to interpret blood work in context of the whole person and what is happening. And that is one issue we do see with getting your own blood work drawn or these online companies. When nobody's interpreting it or helping you interpret it on the other end, you see something that is in a normal range, but it's not at all optimal for you. And it could be the reason why. False reassurance. Yeah, exactly. Okay. So despite a lot of controversial things that might have been said in the rest of the episode, I actually mostly agree with the core claims being made here with a few caveats that I'll explain.

50:38So as mentioned, ferritin is the body's primary iron storage protein. It's also the preferred lab test for assessing iron status. Much more accurate than measuring iron levels in the blood and a lot less painful and invasive than the gold standard test of doing a bone marrow biopsy to measure a person's iron stores. There are some caveats and nuances to interpreting ferritin levels in practice, especially among patients with inflammatory conditions, those with liver disease, kidney disease, but we'll set those aside for now. The bottom line is if your ferritin is low, you're probably iron deficient.

51:15The question though is what is low? This turns out to not be so simple in practice. Ideally, we can find the sweet spot of where we set this cutoff that gives us the best diagnostic accuracy while minimizing the risk of both false positives and false negatives. Lab tests should, as mentioned in the podcast, also always be interpreted in the context of the person's clinical presentation in order to guide our management strategy. So even if you do have a low ferritin with some iron deficiency, it is often not just as simple as just take some more iron. Now the core issue addressed in this podcast, and one that I actually fully agree with is that many labs use a lower limit of normal for ferritin that is far too low.

52:02You'll often see this cut off at 12 nanograms per milliliter, 15 nanograms per milliliter, or micrograms per liter. Now, why is this? Many lab ranges are set by looking at the distribution of values seen among an apparently healthy population, meaning those without active ongoing signs or symptoms of disease and arbitrarily setting the cutoff at the lowest 2.5 % of values. The problem though is when we examine these same populations and we do that bone marrow biopsy test, we find that 30%, 40%, upwards of 50 % of apparently healthy young women, the same types who would be included in these samples, have completely depleted iron stores in their bone marrow, no iron stores.

52:50This is most often due to a combination of menstrual blood losses and insufficient dietary intake to keep up with those menstrual blood losses. So if you set a normal cutoff based on descriptive statistics, rather than based on physiology, you're essentially normalizing deficiency. There's actually no physiologic reason why the normal range for ferritin should be fundamentally different between men and women. And so we need to understand iron status on a spectrum. Most people are familiar with the concept of iron deficiency anemia. This is most well recognized, but it also represents the end stage of iron deficiency.

53:30When your iron stores are so depleted and have been for so long that it's affected your ability to make red blood cells leading to a low hemoglobin level. But non-anemic iron deficiency is where you have low iron stores, but your hemoglobin might technically still be normal. Our body is quite good at stripping iron out of other tissues like our muscles to prioritize it for blood production. This state is often missed or it's disregarded, and this unfortunately leads to undertreatment. We start to see the consequences of iron deficiency well before people become anemic, if we know what to look for.

54:09This suggests that the lower limit of normal is probably higher than most standard lab reference ranges suggest. For example, low iron stores can impair exercise performance and can contribute to symptoms like fatigue. We have multiple double-blind, randomized, controlled trials that have shown that women who are non-anemic but have ferritin levels below 50 can experience significant improvements in their fatigue, their VO2 max, and even their exercise performance when they take supplemental iron. Iron deficiency is also strongly linked to restless leg syndrome as a result of low iron stores in the brain.

54:47Supplementation can help, with some evidence suggesting an even higher threshold of at least 75 for this condition. And finally, studies using advanced biomarkers find that the body's methods to compensate for iron depletion don't actually return to their baseline non-deficient levels until ferritin gets at least to 50 or higher. Now, my only point of disagreement with the podcast is the framing that we are progressively more accepting of lower levels, quote, as the population gets sicker. They seem to imply that we are setting new cutoffs based on an increasingly sick, increasingly anemic population, allowing these levels to drift further and further downward, which is just not accurate.

55:33While it is true that many reference ranges are set on a sort of convenient sample of an, quote, apparently healthy population, the actual lower limit cutoffs of ferritin have been getting increased in recent years, not decreased due to a sicker population. While the WHO still maintains a general cutoff of just 15 for apparently healthy individuals, in 2020, the American Gastroenterological Association increased their cutoff to 45. The American Society of Hematology currently uses a cutoff of 30 and suggests that you can use 50 for people with signs of iron deficiency or ongoing risk factors like ongoing menstrual blood losses.

56:17So while this area is still evolving, these limits are not dropping lower due to a sicker population. As we recognize this, we're actually increasing them as we learn more about the physiology. And so while one side might frame issues with these lab cutoffs as accepting of a more sick population, the other and unfortunately more conspiratorial side tends to frame these things as we're just changing cutoffs so we can sell more drugs. We saw this with changes to recommended blood pressure cutoffs and blood cholesterol cutoffs. Now, it wasn't true in these situations either, but that's a discussion for another day.

56:53Sometimes you just can't win. The takeaways here are pretty straightforward. Don't accept a lower limit of, say, 18 as normal, especially if the person is experiencing symptoms that could be suggestive of iron deficiency, whether or not they have anemia. For most people, using a ferritin lower limit of 50 is reasonable. You could do a lot worse than the recommendation from the podcast of aiming for 60 to 100. I, in my practice, typically use oral or IV iron, intravenous iron, and treat to a target of at least 50 in general and over 75 for those with restless leg syndrome, while also evaluating and treating for the potential causes of iron deficiency like blood loss or intestinal diseases, absorption problems, etc.

57:40Ultimately, I do think that we should be testing patients and women in particular more broadly for iron deficiency. We should interpret results based on symptoms and physiology and treat iron deficiency earlier and much more aggressively. So thanks for tuning in and I look forward to your thoughts and any further discussion on this topic. And that brings us to the end of our review for part one. Now our goal with this episode wasn't to be negative, but more to provide a filter. There's so much information coming at you from influencers and even credentialed experts on large platforms. So it's vital to distinguish between a mechanism like a hormone spike in isolation and an outcome that actually matters to your life and training, like the amount of strength and endurance gained from exercise or your bone mineral density or having a fall.

58:25Now, if you want to train for health, find something that you can do consistently. If you want to get strong, lift weights. And if you're feeling fatigued, we shouldn't overlook anemia. We should still train and auto-regulate it, but don't let the fear of, quote, cortisol or hormone matching keep you from moving your body. Big thanks to Dr. Lauren Colenzo-Semple and Dr. Austin Baraki for their expertise today. If you found this helpful, please leave us a review and share it with a friend who might be confused by the noise. For Barbell Medicine, I'm Dr. Jordan Weigenbaum. Thanks for listening. We'll catch you next week for part two.