
Episode 381: PhysFlex Cert Closing Tonight: Eustress vs Distress, the 4 Pillars, and Applying Recovery Tools the Right Way
About this episode
In this short Flex Diet Podcast episode, I share a reminder that the PhysFlex Surge enrollment closes Monday, April 27, 2026 at midnight PST, and I give more context on what’s inside the PhysFlex Certification. I explain how Level 1 (Flex Diet Cert) covers nutrition and recovery basics, while Level 2 (Physiologic Flexibility) focuses on becoming more robust and resilient by improving the four pillars of homeostatic regulation: temperature, pH, fuels (including ketones), and air (managing oxygen and CO2).
I walk through my eustress vs distress model, why most interventions work better with lower intensity and higher frequency, and how misapplying tools like cold immersion, sauna, or breathing methods can backfire without the right context.
Episode Sponsor:
- Physiologic Flexibility Certification: https://physiologic.miketnelson.com/sales
Available now:
- Grab a copy of the Triphasic Training II book I co-wrote with Cal Deitz here.
Episode Chapters:
- 00:17 PhysFlex Surge Deadline
- 01:10 Who the Cert Is For
- 01:55 Four Pillars Overview
- 02:31 Time Cost and Zone 2
- 03:16 Sauna and Cold Progression
- 04:16 Eustress Versus Distress
- 05:01 Training Frequency Principles
- 07:43 Course Structure Breakdown
- 08:30 Research Meets Application
- 09:29 Context Matters Example
- 12:32 When Interventions Backfire
- 14:29 Wrap Up and Reminder
- 15:12 Medical Disclaimer
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- YouTube: https://www.youtube.com/@flexdietcert
- Email: Miketnelson.com/contact-us
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Flex Diet Podcast — Episode 381: PhysFlex Cert Closing Tonight: Eustress vs Distress, the 4 Pillars, and Applying Recovery Tools the Right Way. Machine-transcribed; use the interactive transcript above to jump the player to any line.
Let's go on on. Welcome back to the Flex diet podcast. I'm your host, Dr. Micci Nelson on this podcast. We talk about all things to increase muscle, increase performance, prove body composition, do all of it, a flexible framework without destroying your health. Today talking a little bit about the Fizz Flex surge. It does close tonight, Monday, April 27th at midnight, Pacific Standard Time. This is 2026. I'll put a link down below with it has all the details and all the information. If you get to it after that day, you'll still be able to get on to the wait list for the next time it's open, which is most likely going to be this looks like probably October of 2026. So you still got a little bit of time. I also got a couple bonus items there for you and just
wanted to give you a little bit more information about the Fizz Flex Sert and then send you this reminder below. If you're looking for ways to be more robust, anti-fragile, increase your recovery ability and just generally be harder to kill this is the certification for you. So the level one will be the Flex diet certification, which covers nutrition and recovery, a little bit of exercise and movement. And then the level two is the physiologic flexibility certification. We're once you're pretty good with your nutrition recovery and basic sleep. This would be the next level of interventions that you can do to increase your ability to be more anti-fragile and just more resilient to overall stressors both in your life and from training. We cover the four pillars of homeostatic regulation, which is number one temperature. Can you be exposed
to warmer and colder temperatures and do okay? Two would be pH. Three would be fuels, which we expand into lactate and ketones as fuel sources. And four is air, which is how you manage oxygen and CO2. If you get better at each one of those areas in my biased opinion, that makes you much more resilient and robust. The good part is like the biggest complaint about adding additional things to your training is the factor of time. And while it is true that some of these interventions, like we talk a fair amount about, to zone two cardio, they do add more time. Zone two cardio is probably the biggest one from a time investment. However, most of them are relatively short. If you're doing a true high intensity interval training, you most people I've worked with, they actually do less work. Although the quality has to be higher and your perceived
exertion normally is much harder. So you're going to harder, but for shorter periods of time, therefore keeping the quality of work high. Most people I work with, if they start sauna or cold water immersion, they tend to add too much time or intensity too fast. I've seen much better results with going slower on that. So less time in the cold or in the heat and changing the parameters. So it's not as bad, meaning temperature wise for sauna is going to be a little bit lower if you can control the temperature. Sometimes you can't. Ditto with cold water immersion with cold water immersion. Most people, if you can control temperature and time, if you have somewhere you can do it yourself or if you're just using cold water in a shower, you may be limited. However, if you can control that, I have people started around 50 degrees Fahrenheit for literally just 30 to 60 seconds, which really isn't that much. And the
progression that I did myself took about two years to get down to 42 to 43 degrees for five minutes. Now, again, the model we're using for this is what's called the use stress EU STRESS. So it's stress that you can apply to yourself and your physiology, but you can generally recover from in a relatively shorter period of time. So I'm a huge fan of doing more of the use stress model with increased frequency and not as much on the stress. So if you told me, okay, my options are to do one super hardcore sauna session a week or I can do a little bit shorter duration, a little bit less temperature, but do more frequent, ie, maybe three to four days a week. I believe the ladder is going to be far superior. This kind of goes back to my training philosophy, too, that high quality work done with higher frequency. I feel you're going to get
much better results than more infrequent, but high intensity training. I just feel like the adaptations you get are much better. This goes all the way down the list from motor learning to nutritional components support, muscle protein synthesis, etc, etc. The same idea would apply to the interventions. You would do that are covered in the physiologic flexibility. So I like doing things that are more of the use stress model that are within the ability of your body to recover within 24 to 48 hours. Now, again, there is a time and a place for distress training, distress, meaning it's going to take you much longer to recover, typically in the model that I'm covering in the search. And even in the flex diet, sir, I use this exact same model. Distress training is typically going to be a competition day or for people who are not competing a test day, taking a little bit of a D load and you're checking your performance. Or you've got a
huge amount of life stress that happens. And sometimes you just end up with distress training due to life events, you possibly do to travel or other things going on. The key is deciding that you are going to do a distress session on purpose. Most people, if I view their training, people, these are people who are training, they're probably intermediate to advanced level already. They're making it to the gym three to four times a week. They're doing mostly intelligent training. I feel they get better result by turning down the intensity, doing more high quality work, and then adding frequency first and then duration. So if they're lifting three days a week, they could maybe go to four days a week, but have the sessions be a little bit paradoxically easier. I think you're going to get much better adaptations. So same thing with the interventions here with the physiologic flexibility certification. The good part of that model is that the time that you spend on them is actually
going to be less per session. So again, it's these same principles. I get obsessed with one or the overarching principles that govern this. Once we figure those out, it is rather easy to figure out how to apply them. And the nice part is these principles don't really change that much. But I still use the use stress distress model in the flex diet search. Again, I use that for the physics like cert also. And then how the course is set up a similar idea as in the flex diet search, you have your big picture of what is a concept of homeostasis or your homeostatic regulations or your regulators and how this applies to all of your physiology. That's going to be part one is the big picture that's going to iterate and go through the entire certification. As you mentioned, we've got the four pillars. So we're going to be a detail the technical video. What is the research? A what are the mechanisms involved? Again,
this is based on human data. There is some fuzzy rat data in there once in a while for mechanistic stuff where we don't have human data yet. Most of it is based on actual human data. You'll learn the intricacies of it. And then part three is the explicit action items. This is so that you can learn how to directly apply it. So all the best information in the world doesn't do anything unless you can apply it. And one of the issues I've seen with other certifications is they're either pretty good on kind of the research side. They get that generally correct. But they are completely miserable on how do you actually apply it? And I've seen other things where the application of it is pretty good. But the rationale why is either completely wrong or not even existing at all. My bias belief is that you want to understand the context. If you don't understand the context of how you are applying these at worst, you're
at the best case, you're not very effective. Worst case scenario, you potentially can be dangerous or you can drive people into the wrong adaptations. The example I used on a previous podcast here was if you have someone where they're over breathing, they are off-gassing or exhaling too much CO2. The last thing you would want them to do is a lot of super ventilation methods, i.e. kind of Wim Hof type style breathing. Again, that doesn't mean that type of breathing is bad or incorrect. It just depends upon the situation. If you have someone who is already over breathing, they are off-gassing, they're exowing too much CO2. The respiratory rate is elevated at night. The last thing you want to do is push them further down those adaptations. You want to go the opposite direction. If anything, you'd want to do CO2 retention methods. I talked about this in the previous podcast. You'd want to do some zone two stuff, some cadence stuff, nasal breathing. Again, this is a
lot of from shift adapts. Brian McKenzie, his stuff, Dr. Annie Gelpin, has talked a fair amount about this and other people too. I even Patrick McEwen and his book has talked a lot about that too. So again, neither one of those interventions are necessarily bad. We just want to make sure that you're applying the right intervention at the right circumstance, which is why you need to understand one, the overall context of why you're doing this, where it fits in. And then you do want to understand the physiologic mechanisms so that you can think your way through the hard part with a lot of these more complex physiology topics is there is not a simple straightforward easy answer. If there was, I would have written this as an ebook and it would be five pages and would just tell you exactly what to do. Unfortunately, we're not at that level of understanding physiology yet. We probably will not get there for anytime soon. The good part is we can understand the physiology and in the cert, I explain it to
you in terms that you can understand. You don't need a thesaurus next to you to try to figure all this out. And then you can apply them either to yourself or if you're a coach with your clients. And then when you do that, you get the right intervention in the right context. And their adaptations and the results are going to be greatly in hand. The beautiful thing about physiology is that it's always constantly adapting. If that is true, the question then is what is the stimulus that we want it to adapt to? We want to make sure that is going to push your physiology into the right direction. I'm big of pet peeve with a lot of these interventions from cold water immersion to sauna to breath techniques is that not that they're necessarily bad per se is that the concept of context isn't talked about. It is typically one intervention that is pushed as the be all end all intervention just do this and it'll fix all your problems. And
for the right context, that can be true for the wrong context. Again, that's going to drive you in the wrong direction. Similarly again, if I'm picking on Wim Hof breathing just because it's popular and easy to pick on, I've had some athletes where the heart rate variability, their stress scores were getting completely screwy. One athlete in particular a couple of years ago, we went through all their training, went through their nutrition, went through their sleep, we're looking at it with or have all of everything as being monitored. Life made I couldn't figure out what the heck was going on. But I asked them, I said, what are you doing different? They're like, oh, I started doing cold water immersion at like 42 degrees for five minutes every day. And I added in 10 minutes of Wim Hof breathing beforehand. What we saw was their stress went absolutely through the roof because adding cold water immersion, adding Wim Hof breathing, both of those things can be very beneficial. But they are stressors upon your system. And this athlete had never done either one of
those and not used a use stress approach. And this was more of a distress training. Again, added on top of their other training that was already on the razor's edge. So that was enough to push them over where the resting heart rate went up, their HRV drop, they're having a hard time recovering. They felt like crap. They felt good after cold water immersion and the Wim Hof breathing. But only lasted a couple hours. And then they would crash afterwards. And they started consuming more caffeine to get through their training and that hard time sleeping at night. Again, we need to back up and look at what is some of the root cause of this. Keep an eye on stress. Go back to what is a model that we are using to evaluate all this. Again, I'm biased to the use stress versus a distress model. And look at each particular intervention. The good part is when we find the right intervention, we can see some positive additive results by incorporating these things in. So that's today's very
short podcast. I just wanted to provide some context that some of these interventions, again, can be super useful, which is a whole point of the certification. But the other side of that coin is that some of these interventions can actually push you into the wrong direction if they are not want to apply correctly and to apply to the correct circumstance or context. You need to understand the big picture. You need to understand each intervention. And then you need to know how to correctly apply each one of those. And to again, is the framework that I use for both the flex side cert and the fizz flex cert. This podcast is for informational purposes only. The podcast is not intended as a substitute for professional medical advice, diagnosis or treatment. You should not use the information on the podcast for diagnosing or treating a health problem or disease or prescribing any medication or other treatment. Always seek the advice of your physician or other qualified
health provider before taking any medication or nutritional supplement. And with any questions, you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have heard on this or any other podcast. Reliance on the podcast is solely at your own risk. Information provided on the podcast does not create a doctor patient relationship between you and any of the health professionals affiliated with our podcast. Information and statements regarding dietary supplements are not intended to diagnose, treat, cure or prevent any disease. Opinions of guests are their own. And this podcast does not endorse or accept responsibility for statements made by guests. This podcast does not make any representations or warranties about guest qualifications or credibility. Individuals on this podcast may have a director, indirect financial interest in products or services referred to therein. If you think you have a medical problem, consult a licensed physician.
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