JOIN THE CIRCUIT CLASS! Come and get involved Tuesday 21st March, 6:30pm Turnham Green, Chiswick
Edition 58: While Everyone Is Obsessed with Ice Baths, Don’t Ignore This Easy Health Win
Ice baths are ironically hot right now. They are the ‘in’ thing that everybody in the world of health and fitness is talking about, and perhaps rightly so (you may have even first learned about in this newsletter). There is a growing body of evidence suggesting a whole world of benefits to a regular cold plunge or cold shower, from improved mental toughness and resilience, to enhanced mood and feelings of wellbeing, reduction in body fat and so on. Initially popularised by cult heroes like Wim Hoff, you can now even buy portable cold plunge tubs to get your ice fix, as opposed to the old wheelie bin trick from back in the day. However while all of this hype engulfs our social media experience (mostly on instagram), there is a less glamorous, but far better researched body-temperature-altering practice which seems to be flying under the radar for most people.
Source: Twitter @SteveMagness
The benefits of sauna have been studied at least as far back as the 60’s (well, that was the earliest study I could find), and the research has specifically looked at its ability to improve cardiovascular condition. Some studies looked at the acute effects of sauna (immediately after), some looked at the short-term effects (2-4 weeks) and some looked at both. Whether hot (sauna) or cold (ice bath) studies, there really isn’t anything conclusive about long term effects as of yet, but certainly in the short to medium term for sauna, the results look pretty strong.
Sitting in the sauna will elevate your heart rate to a high BPM (beats per minute) as you can see below from my 15-minute Tuesday sauna (just before 4pm), it raised my heart rate to around 123 bpm. Now, some might think this potentially dangerous for unfit people, older populations or people with heart problems, but the research has actually shown the activity to be of low risk for most people with cardiovascular disease, and as you will see - it should actually be specifically recommended for those populations (but please if you are in this group, DO NOT take me at my word and always seek professional medical clearance first, I am definitely not a doctor).
A 2020 meta-analysis of 16 individual sauna studies found that blood pressure was reduced by 5.55 and 6.5 systolic and diastolic respectively. The so-called healthy range for blood pressure is anything below 120 systolic / 80 diastolic, so if you’re currently sitting at a slightly elevated level eg. 125/85 and want to get down to 119/79, a regular sauna could be a good way to get there.
The proportion of patients with Class III and IV (as classed by New York Heart Association) heart disease decreased by 11% and 12% respectively, and the meta-analysis concluded that overall, sauna treatment was found to play a positive role in the improvement of cardiovascular function and physical activity levels. A study by Laukkanen et al. found that regular use of sauna meant participants reduced their risk of cardiovascular events/stroke that led to death. It also found that by increasing the frequency/length of sessions, the long-term risk of cardiovascular disease also decreased.
‘But what about the GAINZ?’ I hear you gym buffs screaming at me. Well, let’s talk about growth hormone. GH is the hormone we release during strength training, which varies in intensity depending on the signal we are sending (the size of the muscle we are using, the number and size of motor units recruited etc.). Interestingly, one study found GH to increase 16-fold following sauna use! This is only one study though, and it prescribed quite an abnormal approach to sauna use (restricting to 1 sauna per week, but making it an ‘extended use’ session, of multiple 30-minute stints, with breaks in between. So unless you are *desperate* to multiply your GH by that much, I wouldn’t even go near that one.
It is also important to remember - yes, we may be triggering gains in muscle size (hypertrophy), but are we also maximising gains in muscle strength with a post-workout sauna? Well, that remains to be seen. There is a suggestion in the scientific community that a sauna immediately after training will actually hinder strength adaptations, even if there are a series of other rewards to reap. This is where specificity is important, and if you are lifting weights exclusively to get stronger, it may be smarter to sauna at different times away from strength training sessions.
Having a mix of deliberate heat and deliberate cold exposure in our lives is good for us. It improves our Heart Rate Variability (HRV) and makes us respond better to both sympathetic and parasympathetic stimuli, giving us a balanced nervous system, helping fight illness and fatigue, giving us more resilience mentally and generally just making us more badass. So what are you waiting for? Stay on the hype train with the cold showers and ice baths, YES. But don’t forget to go the opposite way and chase that heat!
Sauna Safety Considerations:
Pregnant women and children under 16 should not sauna
Start slow, with shorter time frames and cooler temperatures (if possible) before increasing
Sweat consists of water and electrolytes which will be lost during the sauna, so replace these by consuming 500ml for every 10 mins spent in the sauna (before, during & after).
For men trying to conceive children: Repeated heat exposure can reduce sperm count
(This can technically be countered by using a cold pack during sauna)
“If you can’t handle the heat… get in the sauna”
Movement of the Week: Barbell Box (/Bench) Squat
4 sets of 5-8 reps