In short
How to improve heart rate variability (HRV) by shifting autonomic nervous system balance, with emphasis on sleep and exercise; also discusses cold plunges/saunas and how they acutely vs chronically affect HRV.
Guests
Sarah Ann Macklin and Andy Galpin. Andy Galpin is a performance/fitness researcher and coach known for exercise physiology; Sarah Ann Macklin is a health/wellness host/guest in the high-performance space.
Key claims
Biggest HRV “rock” changes come from removing performance anchors, improving sleep (especially if sleep disorders exist), and exercising (often endurance/cardiovascular). HRV reflects sympathetic vs parasympathetic balance; cold water drops HRV immediately via sympathetic drive, then rebounds above baseline hours later.
Notable examples
Cold plunge HRV drop immediately, then rise for 3–4+ hours; sauna/hot exposure may help more than cold, but exercise still ranks highest.
Written by AI. May contain mistakes. Listen to the episode to check what was said.
Chapters
Tap a time to open that second in VOKey Practices to Enhance HRV
0:10 to 1:18
Discussing primary actions to improve heart rate variability (HRV) such as sleep, exercise, and nutrition.
“If people want to increase their HRV, what would you suggest?”
Understanding HRV and Autonomic Nervous System
1:18 to 3:05
Explaining heart rate variability in relation to the autonomic nervous system and its implications for health.
“And if you have to hedge, this is probably when endurance, cardiovascular type of exercise does seem to win a little bit, you're more likely to see improvements when you see that go up.”
Effects of Cold Exposure on HRV
3:05 to 5:26
Analyzing the immediate and delayed effects of cold exposure on heart rate variability and its physiological responses.
“or anything like that, your HRV will drop immediately.”
Comparing Sauna Use to Exercise for HRV
5:26 to 6:54
Discussing the benefits of sauna use and its comparison with exercise regarding heart health and HRV improvement.
“It has data There's observational studies on it.”
Transcript
Automatic transcript. May contain errors.0:00Welcome to Live Well Be Well, a show to help high performers improve their health and well-being.
0:10If people want to increase their HRV, what would you suggest?
0:14Andy Galpin:Yeah, first thing is, going back to the earlier conversation, remove any performance anchor. That will do it, number one. So if you have a negative health practice, so when people lose weight, HRV tends to go up. When people eat higher quality food, HRV tends to go up. When people exercise, it goes up a ton. Very few things will increase HRV more than exercise. Those things will all shoot it up. If you have, well, in fact, I'll add one more. Nothing will improve HRV more than sleep, especially if you have a clinical or subclinical sleep disorder, which is really far more prevalent than people realize.
0:50Andy Galpin:Those big, huge practices will rocket shoot HRV up. past that, we can start getting into some smaller impact stuff. But that is the overwhelming majority of time. The people that we have doubled HRV in or had huge improvements in that actually had problems with HRV, it's because usually one of those three or four big rocks is being taken care of. The ones that will move it the most for sure will be against sleep and exercise. And if you have to hedge, this is probably when endurance, cardiovascular type of exercise does seem to win a little bit, you're more likely to see improvements when you see that go up.
1:31Andy Galpin:And that may or may not also be associated with a lower resting heart rate. But those are the biggest ways to move it. What about cold plunges and soreness and things like that? Because that's becoming huge. Yeah, but they're not going to have even close to this impact as those other ones I said. So you can actually look. So HRV will change with cold in a non-commonsensical way. so if you get into HRV you get into cold plunge you will see HRV drop actually immediately and this is exactly what it should be so maybe I'll back up a quick second HRV heart rate variability is again this indirect marker of autonomic nervous system and your autonomic nervous system is in multiple parts but the easy way to think about it is just in two parts although again there's more than this you rest and digest there's also freeze in there and then you have your sympathetic drive right?
2:21Andy Galpin:So parasympathetic rest and digest and sympathetic drive is arousal and upregulation and fight or flight and things like that. Great. HRV is telling us kind of where on that balance you are, how much of balance of sympathetic and how much of balance of parasympathetic, right? So we tend to say a low HRV is sympathetic, like you're more switched towards that side. It's not an on and off button, right? It's a gradient here. And higher HRV means more parasympathetic, more down-regulated. So when we say these things like a really low HRV is associated with poor health, it's generally because that's associated with somebody being stuck in sympathetic drive.
2:57Andy Galpin:This could be stress. This could be, you know, poor sleep. This like, okay. So that hopefully that kind of connects the picture a little bit of what's going on. So if you get into a cold water or anything like that, your HRV will drop immediately. This is going to shoot you into sympathetic drive. This is why you get out and you feel you're exhilarated. Your adrenaline has gone up. Cortisol doesn't go up much, actually, like a huge misnomer. It doesn't really change that much after a cold in men or women, like in humans, at least, to be clear on that one. But adrenaline will go way up, like way up, and HIV will drop down considerably.
3:35Andy Galpin:But if you look at that person 30 minutes, 60, 90, up to several hours, three to four hours plus, HIV will climb. in those three hours, four hours, five hours post cold. And it will generally climb for at least three plus hours and it will go way past baseline. And so if I wanted to hack a test, I would say, okay, take your HRV and let's just say it's 20 and get in the cold water. You get out of the cold water, it might be 10. Again, I'm making numbers up here. But an hour later, instead of being 20, you might be at 30. And two hours later, you might be at 40. So it'll have gone way up. That didn't really change your physiology.
4:14Andy Galpin:This is just a compensatory response to going into a huge sympathetic drive. And now you have this parasympathetic rebound. It's the exact same thing that happens with cortisol and exercise. You go exercise right now, cortisol goes up. In the few hours post-exercise, it'll come way back down in a compensatory response. That's what it's supposed to do, right? That's exactly what we're looking for. It's the exact same reason why taking a hot shower or a hot bath at night gets you really hot, but then your body has this compensatory cooling and you have to cool down to fall asleep. So getting really, really hot actually helps you get colder to fall asleep.
4:54Andy Galpin:It's like hormetic stressors, right? Like very classic over-response. So the question really though is if I chronically did ice plunges or cold plunges or something like that, would I chronically improve my HRV? And I don't think that we really have any data to suggest it's really going to be a strong effect. If you like cold plunges from probably, you know, like different topic we can go into at some other point, fine. But that's not, and it wouldn't compare nearly as much as sleep and exercise. Sauna does seem to be pretty effective at that. And chronic sauna use has more data. It has data There's observational studies on it.
5:36Andy Galpin:There's randomized controlled trials. We have epidemiology on it. There's enough there. In fact, there's enough molecular mechanism stuff there to say, okay, generally associated with positive health and probably a really good thing. So I'd probably be more comfortable saying, okay, if you want to use, and again, it's not sauna, it's hot. So it's sauna or any other methodology of that. But the way to think about that is you can get hot with exercise too. and exercise does a lot of other things for you that just sitting in a hot sauna doesn't do so if we're looking at pecking order again i will really go back to exercise and sleep for sure and of course mental health and nutrition yeah but if you're already doing those things or like my grandfather he doesn't exercise he's never hey we don't even know where to start but he uses a sauna.
6:29Andy Galpin:Like, great. It's better than nothing. There are positive things there. The only thing I would really caution one against is saying, oh, the sauna is more important than the exercise, or I don't need to exercise because I'm in the sauna, or I don't worry about my sleep, I'm doing my sauna. Like, the problem we have with these hacks and stuff, not to call it a sauna hack, but you get the point, is when they exceed the baseline stuff. So that's, I think, the most appropriate way to think about this. Thanks so much for listening. To hear the full episode, there's a link in the description.
From the publisher
Watch the full episode: https://youtu.be/XXwgXDeOYJI
Can you actually improve your heart rate variability? Understanding HRV helps reveal how balanced your nervous system really is.This clip explores the most effective ways to increase HRV, from improving sleep quality and consistent exercise to understanding where cold plunges and saunas truly fit in. Sarah discusses how core health habits like rest, movement, and nutrition have the strongest impact on HRV, while short-term stressors such as cold exposure or heat can cause temporary changes but not lasting improvements.
Andy Galpin in conversation with Sarah Ann
Listen to the full episode here.
Watch the full episode on YouTube here.
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