Day 22: Saunas

                When I think of saunas, I think of old, sweaty men sitting around naked. I always believed that the only positive benefit of saunas was that they helped cut water weight, only to be put back on as soon as you consume water. Once again I must give credit to Dr. Rhonda Patrick, this time in Tim Ferriss’ book ‘Tools of Titans,’ for helping illuminate some of the positive health benefits of the sauna.

                Over the past 3 weeks, I have used the sauna religiously after each workout which equates to 4 days per week. On top of this, I am attending hot yoga on 1-2 of my 'off' days, so I am getting a ton of heat exposure!

                In this post, I discuss my use of the sauna, & look at some of the positive benefits that come along with sauna use.

How do saunas work

                Before I jump into all of the health benefits of sauna use, I want to first explain the mechanism behind how the sauna helps the body produce such benefits.

                When you increase your core temperature for a short period of time, you experience a phenomenon referred to as ‘hyperthermic conditioning.’ Hyperthermic conditioning refers to the process of ‘acclimating yourself to heat independent of aerobic physical activity.’ By exposing your body to heat stress, it induces adaptions in your body similar to those induced during aerobic physical activity, that make it easier to perform when your body temperature is elevated during strenuous physical exercise.

            Some of the positive physiological conditions shown to occur from hyperthermic conditioning include improved cardiovascular mechanisms & lower heart rate, increased blood flow to skeletal muscle & other tissues, increased efficiency of oxygen transport to muscles, lower core body during workload, reduced rate of glycogen depletion, higher sweat rate & sweat sensitivity, & increased red blood cell count. 

             Although I will not discuss each of these physiological benefits that are associated with sauna use in this post, I highly encourage you to research how the sauna can induce each of these benefits, as the mechanism is very fascinating.

Muscle Recovery

                The benefit most often attributed to saunas is muscle recovery which is accomplished by reducing the amount of protein degradation that occurs during strenuous muscular activity such as weight lifting. Use of the sauna triggers ‘heat shock proteins’ which create a hermetic effect which helps repair proteins damaged during exercise, helping increase protein synthesis in your muscles, thus helping them recover more quickly.

                In lab tests done with rats, regular sauna use was associated with 30% more muscle regrowth after muscle damage when compared with rats that did not utilize the sauna. Perhaps more interestingly, the expression of the heat stress proteins persisted for up to 48 hours after the sauna session, suggesting that the positive benefits persist well beyond the 20-minutes that you spend in the sauna.

                Additionally, sauna use has been associated with elevated levels of growth hormone which helps combat post-exercise muscle atrophy. In one (admittedly extreme) study, subjects that participated in two one-hour sauna sessions per day for 7 days experienced a 16-fold increase in human growth hormone that persisted for a few hours post sauna. 

                In short, sauna use can help you increase protein synthesis & your levels of human growth hormone, two key components in preventing post-exercise muscle atrophy, & helping your muscles recover more quickly & effectively.

               

Improved athletic performance

                When you exercise, specifically at high intensity, your body temperature increases significantly. It is believed that the effects of ‘hyperthermic conditioning’ discussed above replicate this increased body temperature, offering significant endurance benefits by acclimating your body to performing under heat stress.   

                Heat stress induced by a 20-minute sauna session has been shown to increase plasma volume & blood flow to your muscles which contributes to athletic endurance & muscle mass. One study showed that runners that had 30-minute post-workout sauna sessions twice per week for 3 weeks were able to increase the time it took them to run until exhaustion by 32% versus a control group that did not use the sauna. This same studied showed that participants were able to increase their plasma volume by 7.2% & their red blood cell count by 3.5% relative to peers, two mechanisms associated with increasing endurance during strenuous exercise. 

                 To summarize, sauna use has been linked with two mechanisms in increased plasma volume & blood flow to muscles that are highly correlated to athletic performance. Although sauna use cannot replace aerobic exercise in an effort to increase athletic endurance, it certainly has been shown to be an effective supplement.

                 

Improved Brain Function

                Sauna use has been shown to trigger the release of proteins known as ‘neurotrophic factors’ which activate brain stem cells to produce new neurons which are responsible for enhanced learning. Strenuous exercise has been shown to trigger the release of the same proteins, which is believed to be the reason a physical workout can have such a beneficial impact on brain tissue & stress levels.

                Sauna use has also been linked with increased levels of ‘norepinephrine’ which is a hormone involved in the stress response that increases focus & attention. In one study, sauna use increased norepinephrine in subjects by 310% after the session.  It is believed that the phenomenon known as ‘runner’s high’ uses a similar mechanism to induce increased endorphin levels which produces the feeling of well-being that one gets after an effective workout.  

Relaxation

                More anecdotally, the sauna is relaxing! After a strenuous workout, sitting in a sauna can help you regulate your breathing & heart rate, get in a good sweat, & recharge. Personally, I partake in 20 to 30-minute sauna sessions after every strength-building workout, a process that I have learned to love. It helps me to relax, reflect, & recharge after a tough workout.

                In conclusion, there is a LOT of information our there linked to how saunas can help improve muscle recovery, athletic performance, & even brain function. I challenge you to try out the sauna for yourself for 20-minutes post-exercise for a few weeks, it has become an integral aspect of my post-workout recovery process & I can’t see myself changing it.

100 Day Spartan