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Sauna effect on heart rate

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Re: Sauna effect on heart rate

#191

Post by PaulDavisThe1st »

Noaidi wrote: post #106
kyriakosel wrote: post #2

Author here. Methodology upfront because I'd ask the same things: Data: daily records from wearable users who logged sauna sessions via connected apps. Within-person design — each user is their own control, comparing their own sauna-day nights against their own non-sauna-day nights. No cross-user comparisons. Stats: paired t-tests, FDR-corrected p 0.2 threshold for "meaningful effect." Anything below d=0.2 we don't r…

Just because your heart rate is lower does it mean you’re any healthier however. This is just ridiculous measurement it means nothing. The sauna might be acting like any other drug. There are a lot of drugs that will lower nighttime heart rate. Does that mean those drugs are healthier for you?

If your resting heart rate is lower without any drugs, it indicates that your heart can cause sufficient oxygen to be delivered to your organs with less effort than if it were higher. That can be caused by a variety of things (including stroke volume, capillary dilation and general obstruction (or not) of blood vessels). These are all good proxies for general health.

Drugs lowering your resting heart rate do not indicate this in the same way.

Re: Sauna effect on heart rate

#192

Post by PaulDavisThe1st »

asdfman123 wrote: post #151
MyHonestOpinon wrote: post #139

I try to do 180 minutes a week of cardio. Mostly Zone 2. Biking, elliptical, tKD. But once in a while my legs feel too tired, so I complete my weekly minutes going to the steam room. It makes sense to me since it raises your heart rate. Also, my samsung watch can measure stress (whatever it means). It always shows the very, very minimal stress for me. The only time that I have been stressed was the day that I spent a…

FWIW you should probably be doing some max intensity, or at least high intensity cardio. Zone 2 is great but the best health outcomes are from people who do high intensity exercise interspersed with zone 2 exercise.

This is contested by a significant number of contemporary running coaches (see, for example "Training for Uphill Athletes" by Steve Johnson or any of the life work of Phil Maffetone.

HIIT is quite effective at something; it's not clear that it is effective at all possible exercise goals (including, but not limited to, endurance running).

Johnson in particular says that unless you've already narrowed the gap between your "first" and "second" (anaerobic) threshold to 5%, HIIT really doesn't make much sense because you're "aerobically challenged" and need to work on that first, which he believes (with significant evidence) is best done almost entirely in zone 2.

He also notes that someone like Eliud Kipchoge can spend 2 hours running 4:30 min/mile pace, so that is clearly within his aerobic range, but that Kipchoge would never and should never spend much time training at that pace because of the load it would put on his system. So the zones that are used for training purposes depend significantly on the current fitness level of the athlete.

I have used HIIT effectively to get myself out of certain fitness/training "ruts", but I think that the zone 2 folks have somevery cogent and coherent observations and advice.

Re: Sauna effect on heart rate

#193

Post by PaulDavisThe1st »

gcanyon wrote: post #38

N=1, but I started rowing (indoor, on an erg) an hour a day -- not hard, generally 120-140 bpm -- every day starting February 28, after rowing inconsistently for a year or more before that. My resting (not sleep) pulse has dropped by 10% over the past ~7 weeks, from 60 to 54.

General advice: citing absolute HR numbers is pretty meaningless for a broad audience, because they are not intepretable. Express them as percentages of your current max HR to be meaningful to others.

Re: Sauna effect on heart rate

#194

Post by sd9 »

asdfman123 wrote: post #152
eggy wrote: post #112

A delta of 3 bpm on sauna days corresponds to around 4% delta if the baseline is 72 bpm. I've gone from a resting heart rate over a 7-day average of 64 bpm to 58 bpm by jumping 15 min. of rope a day, 4 times a week. I've lost weight, body fat, and I feel like my body is more efficient with corresponding lower heart rates throughout my active day. I like saunas for recovery and aches, they put me in a relaxed state af…

PSA: if you like saunas but don't have easy access to one, those IR sauna bags you can buy online work great. Some people find it gross to basically sweat inside a powered sleeping bag, but if you don't mind that you can get the same effects of a sauna while lying on your (covered) couch and watching YouTube.

Wow, they look really quite dangerous. I wouldn’t want to pass out in one. Yeah you can pass out in a sauna too, but it feels easier to lurch for the door than to fight with a sleeping bag.

Re: Sauna effect on heart rate

#195

Post by PaulDavisThe1st »

dtran wrote: post #181
atum47 wrote: post #161

Should I assume a steam room has the same effect? I prefer it over sauna

Potentially, but likely much less effective and less studied, and you likely need longer sessions for effective dosage. Most of the studies I've seen on improvements in blood plasma volume from passive heat are usually done with sessions in saunas with temperatures > 150 degrees F (60 C). Steam rooms usually only get up to 120F (~49C) even though the humidity probably makes it feel warmer. Copying and pasting some of…

Sweating is one the main triggers for an increase in blood plasma volume, and the humidity level of a steam room causes vastly higher rates of sweating than most saunas do. You can lose significant body heat by sweating in a dry environment, but much less in high humidity. Consequently, your body needs to sweat much more rapidly even though the absolute temperature may be lower.

Re: Sauna effect on heart rate

#196

Post by dtran »

PaulDavisThe1st wrote: post #195
dtran wrote: post #181

Earlier quoted context omitted.

Potentially, but likely much less effective and less studied, and you likely need longer sessions for effective dosage. Most of the studies I've seen on improvements in blood plasma volume from passive heat are usually done with sessions in saunas with temperatures > 150 degrees F (60 C). Steam rooms usually only get up to 120F (~49C) even though the humidity probably makes it feel warmer. Copying and pasting some of…

Sweating is one the main triggers for an increase in blood plasma volume, and the humidity level of a steam room causes vastly higher rates of sweating than most saunas do. You can lose significant body heat by sweating in a dry environment, but much less in high humidity. Consequently, your body needs to sweat much more rapidly even though the absolute temperature may be lower.

To my understanding, while sweating is important to heat adaptation and blood plasma volume adaptations, thermal load and cardiovascular strain are likely bigger factors (and more important for the health benefits mentioned in this study). Overall thermal load is still higher in a hotter dry sauna than in a steam room

Re: Sauna effect on heart rate

#197

Post by cpursley »

xtracto wrote: post #149
Insanity wrote: post #123

Earlier quoted context omitted.

The great but not super healthy Mexican diet might offset the potential heat exposure benefits! Although I’m basing that on the diet of my Monterrey-based in-laws, not sure how different Yucatan is.

LOL, Monterrey diet is healthy compared to the diet in the Yucatan peninsula. Tamales, Cochinita (roasted pork with herbs), salbutes, trancas. Everything of course cooked in Lard. With CocaCola on the side. So yeah, that's a strong point.

Lard is fine as is pork, it’s the sugar and carbs.

Re: Sauna effect on heart rate

#198

Post by PaulDavisThe1st »

dtran wrote: post #196
PaulDavisThe1st wrote: post #195

Earlier quoted context omitted.

Sweating is one the main triggers for an increase in blood plasma volume, and the humidity level of a steam room causes vastly higher rates of sweating than most saunas do. You can lose significant body heat by sweating in a dry environment, but much less in high humidity. Consequently, your body needs to sweat much more rapidly even though the absolute temperature may be lower.

To my understanding, while sweating is important to heat adaptation and blood plasma volume adaptations, thermal load and cardiovascular strain are likely bigger factors (and more important for the health benefits mentioned in this study). Overall thermal load is still higher in a hotter dry sauna than in a steam room

That's not my understanding, but my understanding is somehwere between 3rd and 6th hand, so it's likely not worth much.

Re: Sauna effect on heart rate

#199

Post by socalgal2 »

kyriakosel wrote: post #2

Author here. Methodology upfront because I'd ask the same things: Data: daily records from wearable users who logged sauna sessions via connected apps. Within-person design — each user is their own control, comparing their own sauna-day nights against their own non-sauna-day nights. No cross-user comparisons. Stats: paired t-tests, FDR-corrected p 0.2 threshold for "meaningful effect." Anything below d=0.2 we don't r…

> Sauna days are more active, which fits how people actually use saunas, often as a post‑workout routine

WAT? As far I as know there is no such connection between workouts and saunas in Finland, nor in Japan

Re: Sauna effect on heart rate

#200

Post by pstuart »

PaulDavisThe1st wrote: post #190
pstuart wrote: post #130

Earlier quoted context omitted.

Dr. Rhonda Patrick has been beating the drum for saunas for a long time, and she's reported that a hot tub can be equivalent or better: https://x.com/foundmyfitness/status/1955294334535995850?lang...

David Roche, a notable running coach (and runner), and his co-coaching wife (and runner) Dr. Megan Roche (MD/PhD) seem to think that hot tubs need to be at least 106F to generate much of a heat shock response, which is normally what one is looking for in the context of post-exercise heat exposure. I should note, however, that they are mostly reading the same research papers as everybody else, not doing primary studie…

Being that the recommended max temperature for hot tubs is 104F that could be an issue. Hot tubs are definitely more pleasurable than saunas, and if it comes "close enough" I'd be fine with that.
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