We have seen an explosion in the wellness market in terms of recovery offerings – everything from traditional sauna’s to infrared sauna’s, cryotherapy and ice baths.
I recently jumped on the band wagon and had an infrared sauna installed in my gym. I have to admit, I didn’t quite understand what all the fuss was about. I knew I felt better, relaxed and calmer after being in one but surely there were other health benefits apart from relaxation?
As it turns out there was! This led me down a rabbit hole of research papers on this very topic and what I discovered changed the way I do recovery forever more.
Heat and cold therapy have become a non-negotiable part of my daily and weekly protocol, and I must admit, I have never felt better.
Before embarking on any heat journey of your own it is important to take note of some safety considerations. Using sauna’s that are too hot can be detrimental to your health.
So, what is too hot? According to Dr Andrew Huberman a Professor at Stamford University this will depend on the individual. He recommends starting off slow using cooler temperatures that don’t significantly increase the heart rate. Hyperthermia (abnormally high body temperature) and dehydration are a real risk so proceed with caution.
Pregnant women, children under 16 and men trying to conceive should also avoid using saunas as this can reduce their sperm count.
What’s All the Fuss About:
Heat is a remarkable stimulus, meaning when we are in a hot environment it has a profound effect on our biology. Heating up from the outside or the inside has a profound effect on many different aspects of our health including our metabolism, both in the immediate and long term, our cognition (meaning our ability to think more or less clearly). If you assume heat negatively affects the way we think you are wrong, heat applied as a stimulus can engage certain neurochemical systems in the brain and body that can allow your brain to function far better.
How do we Heat Up?
We heat up in 2 ways –
- From the outside meaning the things we come into contact with our clothes that we put on our body. Whether there is heat in the room, whether it is cold inside or outside in our environment.
- From the Inside – Our body has the capacity to generate more heat or to cool down or to turn off the heating process. It can do that in ways that match the external environment.
Heat & Cardiovascular Health:
Study 2018 – “Sauna bathing is associated with reduced cardio vascular mortality & improves risk prediction in men and women – a prospective cohort study”)
One of several papers that clearly demonstrates that regular use of sauna or other forms of deliberate heating exposure can reduce mortality to cardiovascular events but also other events like stroke etc.
This study looked at a sample of 1688 participants (mean age of 63) and of whom 54% were women and the rest men. Basically, what they found was the more often that people do sauna the better their health was, and the less likely they were to die from a cardiovascular event.
Further, the use of sauna has been studied by other clinical groups and positively correlated with a ‘reduction in all-cause mortality’ – a catchall term referring to death from any cause.
What do we Mean by Sauna and What are the Parameters?
Firstly, the temperature ranges that were used in this study were 80 degrees celcius (176 degrees farenheit) and 100 degrees celcius (212 degrees farenheit). What temperature should you use? This all depends on how tolerant you are and heat adaptive you are, yes this tends to get better over time.
Recommendations are to start on the lower end of the temperature scale and work your way up. These people were going anywhere from 5 to 20 minutes per session. Even if it just 5 mins of heat exposure can make a difference as long as the temperature is enough for you.
In this particular study they compared people that did sauna 1 x a week to ppl who did 2-3 x a week or 4-7 x a week. What they found was remarkable, what they observed was that people that went into the sauna 2 or 3 x per week were 27% less likely to die of a cardiovascular event than people who went into the sauna 1 x per week. The temperature levels and the duration levels as above.
This data points to the fact that going into the sauna at least 2 x per week can lower mortality to cardiovascular events and the benefits were even greater for people going into the sauna 4 x per week (50%) less likely to die of a cardiovascular event compared to people that went in 1 x per week.
This study also looked at confounding variables as to whether people smoked were overweight, exercises or not etc and they were able to separate out these variables.
Sauna as a Mood Enhancer:
The use of sauna’s has been around in Scandinavian culture for hundreds of years. Even back then it has been well known about the correlation between sauna use and improved mood.
The body responds to heat by releasing hormones such as dynorphins and endorphins in the brain. Dynorphins are responsible for causing discomfort thru heat exposure in the short term. These dynorphins create impulses in the brain, for example, like wanting to get out to avoid the discomfort or feelings of agitation.
This dynorphin leads to a further biochemical reaction, the release of endorphins (feel good hormone). The release of endorphins improves our mood leading to feelings of euphoria and happiness.
Effects of Sauna on Stress & Overall Health:
According to Huberman, “Hormesis is mild, tolerable stress that stimulates the body and helps it to positively adapt’. Heat is a form of hormesis stress and there are plenty of other forms such as exercise etc. Studies have found that regular use of sauna can reduce cortisol levels (stress hormones), enhance the activation of DNA/longevity pathways and promote heat shock proteins (HSP) in the body. These HSP are a protective mechanism in the brain and body that help rescue cells in the body that are damaged or misfiring. Damaged or misfiring cells can develop into more sinister illnesses and disease which is why these HSP are so important to our health and wellbeing.
Huberman found that in order to gain the benefits of deliberate heat exposure for general health, including improved mood, stress management, and the enhancement of the bodies hermetic (mild stress) response pathways, use sauna for a total of:
- 1 hour per week, but not all at once, rather split that into 2-3 sessions.
- Sauna temperature should be between 80-100 degrees.
Use of Sauna to Increase Growth Hormone:
Growth hormone is a hormone we naturally secrete from our pituitary gland (resides near the roof of our mouth). Growth hormone plays a key role in stimulating muscle growth (growth spurts), increasing bone density, repairing tissue and increasing metabolism.
Growth hormone is released at night when we sleep which is why sleep is an important factor on our overall health. Growth hormone tends to decline as we age which can lead to decreases in bone health, loss of muscle mass and decreases in metabolism.
In one study – ‘Endocrine Effects of Repeated Sauna Bathing” 1986 paper found dramatic increases in Growth Hormone by up to 16 fold.
The protocols from this study found for improved release of growth hormone use the sauna:
- 1 x per week or less
- On the days you do sauna go in for multiple sessions per day of 30 minutes each with cool down periods of 5 minutes in between. This study found this protocol works well to increase growth hormone repeat this process 2-3 times.
- Have a few hours off and repeat the above again
- That’s a lot of sauna’s!
- Use the sauna in a semi-faster state to get maximum release of growth hormone having not ingested food for 2-3 hours prior.
For what it’s worth, the best heat exposure for you is the one that you can readily access and the one that fits in with your lifestyle.
It also depends on what results are you after!
If you are after growth hormone then try the 1 x week 4 x per day for 30 minutes – more beneficial when fasted.
If you want the health benefits of cardio vascular reduction then stick to 2-4 times per week for 5-20 minutes at 80-100 degrees.
If you are looking for stress reduction then sauna 1 hour per week broken up into 2-3 sessions of 80-100 degrees.
When you go into the sauna make sure you replace water that you lose in the sauna. Drink 500ml of water for every 10 minutes you are in the sauna. Either before, during or after.