Dr. Stephen Seiler argues breathing frequency is a better training metric than heart rate, especially during intervals. It scales from resting to max effort and avoids cardiac drift. New tech could soon make continuous breathing measurement as easy as heart rate monitoring.
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Are there some things in some of the new bio tracking that excite you? Like what's happening now or what's going to be coming here in the next 3 to 5 years?
The issue that I've been fascinated with in the last year is breathing, strangely enough. You know, it is the— as a group from the UK, they wrote an article about it. It was the kind of the forgotten vital sign or whatever, you know. And if you, if you're unconscious, you've been injured, and you are wheeled into a hospital, the first two things that the doctors or nurses will evaluate is, is your heart beating? Are you breathing? And then more specifically, what's your heart rate? What's your breathing rate? Right? And that has extremely, you know, a lot of value for them in making some initial decisions about the state of your body. These are called vital signs. Now, in sports, we have discovered decades ago the heart rate as a window into the human physiology, into, you know, what intensity am I working at relative to my max. And it's a powerful tool, and we've done a great job in in making that accessible to people and pretty good job at calibrating it and so forth. But there are situations, there are movement situations, training situations where heart rate does not tell you everything you would like to know. For example, during interval training, during these different kinds of stochastic work with lots of variations in tempo and that heart rate kind of may find a middle zone that is reflective of the overall oxygen demand, but your brain is saying, "Yeah, but this is harder than that." Right? Because those peaks are costing me a lot. Well, if we measure your breathing, even something as simple as your breathing rate, just what breathing frequency are you at? It tracks with the realities that you are facing in terms of getting that work done, of mobilizing, maintaining that pace. In those repeats or in those intervals, even better than heart rate. That is one of the things that has fascinated me. Because I was looking at the heart rate, I have developed some tools. I have spoken a lot about cardiac drift, about internal workload versus external workload. There is no such thing as a steady state during training. We can measure this kind of internal workload shift relative to the external. Does that make sense? Yeah. And it works and it is important and it is useful. It tells us that the first hour of a 2-hour run is not the same as the second hour. The second hour is harder even though the pace is the same. You cannot equate those because they are your efficiency. Things are breaking down in your body. It is costing more to do that same work, whether it is cycling or rowing or swimming or running. So we have to be cognizant of that and we have to understand that intensity has no meaning without putting a duration to it. Does that make sense? Yeah, absolutely! It's a unidimensional construct that only has meaning when we add duration. You know? Right? I can hold any pace up to 1,300 watts for a second, you know? But already after— Crash and burn! Yeah! But already after 10 seconds, I've lost a lot of— you know, and after 2 minutes, it's a different— These power values and pace values only have meaning when I attach a duration to them. We are not in a steady state. Heart rate reflects some of that, but in that very high-intensity regime and the stochastic regime where you are doing lots of this up and down, cross-country and so— ventilation tells us some things. You know that if you have raced, you can hear your competition. How are they breathing? You know, and you make— and there's famous examples of athletes that have kind of come up to the side of an athlete, you know, and can tell they're breathing hard and then they attack, you know, or they hide. They try to hide the fact that they're like, you know, so they're trying to hold their breath for as they run up, you know. So we know it instinctively that breathing is a truth teller, right? So, long story short, we are really getting into the weeds and trying to understand breathing and what it can tell us and whether we can use it as a— we can scale breathing in the same way we can do with heart rate reserve, where you take maximum heart rate versus resting heart rate and you have the percentage of the heart rate reserve. You can do that with breathing too. You can do that with breathing frequency.
Yeah. When does it change over, right?
Yeah. And you can find your athlete's kind of maximum breathing frequency when they are really in the cellar all the way maximum effort. You know what the resting breathing frequency is. It is pretty typical, 12 to 16, somewhere in there. So you can establish this range and then you can use that as an intensity scale. Turns out it has more scope than the heart rate part of the scale. Anyway, I do not want to get too far in the weeds, but that is a variable that is very basic and new technology is making it possible for that to be measured just as easily or easier than heart rate in the daily grind. We will see whether that can add, can help us do a better job of monitoring and perceiving where we are and when to say, "That is enough. I have done enough work today. I am at 85% of my breathing frequency. If I go farther than that, then I am really starting to I'm gonna blow up, you know, then it's too much, you know, and I think we're gonna get there. And so that's, that's an area that I'm spending a lot of time on right now.
I love hearing that. Like, I've previously had, uh, the Iceman Wim Hof on the podcast when we talked about breathing quite a bit and about how you can also, like, if, if you're very highly stressed, how to reset your autonomous nervous system through breathing. And then I had Patrick McCowan on the podcast as well. We talked about nasal breathing quite a bit, which is another topic that I thought was quite fascinating.
Yeah, I've done that. I've tried that.
I saw you on Twitter. Please describe a little bit more about the crossover, what you started noticing.
Well, if you see in the video, I've got a pretty solid nose here, so I probably have some anatomical advantages for nose breathing. Yeah, I saw these initial things about it and I thought— I have done a few workouts, 2-hour rides inside, outside, just breathing through my nose. My question was, and I even had a master's project where we tested this last year, the idea that nose breathing acts as a poor man's kind of governor to make sure you are below your first lactic turn point. It turns out that is not true. It does not work that way. There are, with training, people can get quite good at nose breathing and they can achieve pretty darn high intensities just without opening their mouth. So that does not work. But there are other questions that are kind of interesting. There has been discussion about whether there are different neurological hormonal issues that emerge when you just breathe through your nose. I do not know enough about that. But I just I do know that I find it interesting that, you know, on a good day, if my nasal passages are open and I just breathe through my nose for 2 hours, it is kind of calming. It is kind of, you know, it is kind of like it is almost meditative. And so I have done some nice, easy, steady state, you know, like 200 watts for 2 hours and just breathing through my nose. And it is— I like it. I kind of like it. It has got a certain— I do not know. There is a certain mindfulness aspect to it.
Once you get past the first few weeks, snot bombs that are just dripping out of your nose.
Yeah. Yeah. Well, it's kind of, for me, it's like, there are just days if I'll try and like immediately my brain will just, no, I ain't doing it today. It doesn't work. I'm a bit tight in the nose. Whereas other days, you know, okay, this is going to happen, you know? So it, I kind of, my body just gives me feedback pretty quickly whether this is going to happen or not today. I've pushed myself pretty far up the scale and I was able to get to almost like 300 watts, which for me is a pretty high intensity. Just breathing through my nose.
