- Immune System Boost
The Journal of Human Kinetics recently investigated the effect of sauna use on the immune system, specifically white blood cell profile, cortisol levels and selected physiological indices in athletes and non-athletes. The subjects from both a sauna group and a control group participated in 15-minute sauna sessions until their core temperature rose by 1.2°C.
After the sauna session, an increased number of white blood cells, lymphocyte, neutrophil and basophil counts were reported in the white blood cell profile, showing that sauna use stimulates the immune system (and interestingly, a greater benefit to the immune system was shown in the athletes vs. the untrained subjects, indicating that an excellent one-two combo for your immune system is exercise and sauna use). German sauna medical research also shows that saunas are able to significantly reduce the incidences of colds and influenza and both Finnish and German studies show that regular sauna bathing leads to a 30% less chance of getting a cold and influenza.
- Heart Health & Longevity
A new report in JAMA Internal Medicine shows that regularly spending time in a sauna may help keep the heart healthy and extend life. Researchers from the University of Eastern Finland tracked 2,300 middle-aged men for an average of 20 years. They found that the more sessions per week men spent in the sauna, the lower their risk of sudden cardiac death and fatal coronary heart disease. The sauna also extended the life of participants with other illnesses, including cancer.
According to the study, participants who had two or three sauna sessions a week had a 22% reduced chance of suffering sudden cardiac death. Men who had four to seven sauna sessions of at least 20 minutes each, had the greatest benefits. Compared with those who had just one sauna session a week, they had a 63% lower risk of sudden cardiac death, 50% lower risk of CVD (cardiovascular disease) death, 48% lower risk of CHD (coronary heart disease) death and were 40% less likely to die from all causes.
Researchers reported that the benefit to cardiovascular health was likely due to the decrease in blood pressure and an increase in blood vessel diameter that both infrared exposure and heat exposure can provide.
Having spent time last month in Finland sitting buck-naked in a traditional Finnish smoke sauna, surrounded by old guys who definitely seemed more ripped and vibrant than their fat Western counterparts, I can certainly attest to the fact that there’s something special going on with this Finnish tradition.
- Detoxification Of Chemicals And Heavy Metals
The skin is a major detox organ, and sweating through the skin is a critical human detox function, yet most people don’t sweat regularly or enough. Think detoxing is a woo-woo, airy-fairy, pushing-giant-shopping-carts-full-of-kale-through-Whole-Foods myth? Think again. You may want to read this.
As you’ll see if you read that article above, the body is very effective at eliminating toxins via the skin (and the liver, and the poo), but the skin side of things only really works if you make your body sweat. But many of us sit in air-conditioned indoor environments all day, and even gyms with temperature control can be a tough place to work up a serious sweat. So in these type of situations, you completely miss out on a major source of toxin elimination: the skin.
To combat these effects, a sauna can purify the body from the inside out, eliminating compounds such as PCB’s, metals and toxins that are stored in fat cells, which can undergo lipolysis and release toxins upon exposure to infrared-based heat. Yep, you read that right: you are going to battle against and killing little screaming fat cells to death when you sweat in a sauna. They don’t shrink: they die (especially when combined with niacin, which research has some interesting findings on and which I talk about in more detail here).
- Athletic Recovery
Growth hormone is crucial for repair and recovery of muscles, and research has shown that two 20-minute sauna sessions separated by a 30-minute cooling period elevated growth hormone levels two-fold over baseline. Two 15-minute sauna sessions at an even warmer temperature separated by a 30-minute cooling period resulted in a five-fold increase in growth hormone.
Perhaps even more nifty is that repeated exposure to whole-body, intermittent hyperthermia through sauna use boosts growth hormone immediately afterward, and two one-hour sauna sessions for 7 days has been shown to increase growth hormone by 16-fold. Yeah, that’s right: you don’t need to go buy fancy supplements or creams to increase growth hormone. You can just make your body hot instead and get a growth hormone increase
It is also important to note that when hyperthermia and exercise are combined, they induce a synergistic increase in growth hormone, which is why I do yoga, push-ups and squats in my infrared sauna. For an additional recovery benefit, sauna also increases blood flow to the skeletal muscles, which helps to keep them fueled with glucose, amino acids, fatty acids, and oxygen, while removing by-products of metabolic processes such as lactic acid and calcium ions.
- Arthritic & Muscular Pain Relief
In a report in The Annals of Clinical Research Volume 20, Dr. H. Isomäki discusses research results that show benefits of sauna for relief of pain and increased mobility. In the study, the pain relief induced by a sauna was attributed to an increase in the release of anti-inflammatory compounds such as noradrenaline, adrenaline, cortisol and growth hormones, as well as an increase in positive stress on the body, causing it to releases natural pain-killing endorphins. More than 50% of participants reported temporary relief of pain and an increase in mobility, most likely due to the fact that tissues comprised of collagen, such as tendons, fascia, and joint articular capsules, become more flexible when exposed to increased temperatures.
Now here’s the deal: I don’t actually have arthritis. But I do have some pretty freaking gnarly joint pain the day after I’ve finished a typical workout of heavy squats, sandbag carries, kettlebell swings, hill sprints and tire flips. After my morning sauna session, things seem to melt away (caveat: I have not yet used myself as a N=1 control study by sitting and staring at a wooden wall in normal, non-sauna temperatures, but I’m hazarding a guess it wouldn’t work as well as a sauna, so I’ll skip that study, because it sounds boring).
- Muscle Gain & Fat Loss
Bigger biceps or a more toned butt by reading a magazine while sweating profusely? It could happen. Sauna conditioning can lend itself to promoting muscle growth and fat loss by improving insulin sensitivity and decreasing muscle protein catabolism. Intermittent hyperthermia has been shown to reduce insulin resistance in obese mice, and in this case insulin resistant diabetic mice were subjected to 30 minutes of heat treatment, three times a week for twelve weeks. The results were a 31% decrease in insulin levels and a significant reduction in blood glucose levels, both of which can contribute to an increase in muscle growth and an increase in weight control and fat loss.
It has also been shown that a 30-minute intermittent hyperthermic treatment can cause a significant expression of something called heat shock proteins in muscle, which is correlated with 30% more muscle regrowth than a control group during seven days subsequent to a week of immobilization. In other words, let’s say you can’t weight train, you’ve got a recovery day or you want to maintain muscle but you’re injured. Based on the research cited above, via the use of a sauna instead, you can still maintain muscle.
- Skin Rejuvenation
While exposing yourself to ungodly amounts of time in the sun can make your skin look like Benjamin Button as a baby, the old lady in “Something About Mary”, or an elephant who spent too much time a bathtub, spending time in a sauna doesn’t submit you to the same kind of UVA and UVB rays as you get from the sun. When your body begins to produce sweat via the type deep sweating you experience in an infrared sauna, the rate at which dead skin cells are replaced an be increased. At the same time, heavy sweating helps to remove bacteria out of the epidermal layer of the skin and the sweat ducts.
This cleansing of the pores also causes increased capillary circulation, which can give the skin a softer-looking, younger appearance. When you sweat, the movement of fluid to the skin delivers more nutrient and mineral-rich fluids and also helps to fill spaces around the cells, increasing firmness and reducing the appearance of wrinkles. So by continually flushing waste through skin cells via the use of hyperthermia, you can increase skin health, tone and color, and more effectively cleanse your pores.
Not only does research show this skin rejuvenation effect to be the case, but I’ll admit that I’m quite frequently mistaken as Justin Bieber when I take a stroll down the street after my morning sauna session. So it must be working.
- Better Sleep
Next time you find yourself struggling with a bout of insomnia, try this trick: about two to three hours before bed, hunt down a gym sauna and get your sweat on for about fifteen to thirty minutes. Next, hop in a lukewarm or cool shower for five to ten minutes to bring your body temp down. If you’ve got plenty of time on your hands, you can do this two to three times through. Anytime I do this kind of hot-cold contrast in the evening, I sleep like a baby.
Researchers have found that a sauna can help provide a deeper, more relaxed sleep, and also relief of chronic tension, and relief of chronic fatigue issues, most likely due to a release of endorphins from the sauna. As endorphins are released into your body, they create a soothing, nearly tranquilizing effect that can not only help to minimize chronic pain caused by arthritis and other muscle soreness, but can also help with relaxation and sleep. For an even more enhanced effect, try deep nasal breathing while you’re in there.
- Increased Cardiovascular Performance
You probably know of EPO as the illegal performance-enhancing drug made famous by professional cyclists in Tour De France, but research has shown 30 minutes of sauna treatment after exercise can cause an increase in oxygen consumption and red blood cell production that parallels the use of EPO. That’s right: no needles in the right butt cheek or illegal performance enhancing drugs required. In the high temperatures of an infrared sauna, your skin heats up and core body temperature rises. Then, in response to these increased heat levels, the blood vessels near your skin dilate and cause an increase in cardiac output. This causes your heart rate to shoot up from 60-70bpm (beats per minute) to as high as over 150bpm in the sauna. So with regular sauna use, you not only train your heart muscles and improve your cardiac output, but you also help the body’s regulatory system move blood around the body to areas that need cooling.
Similar to the pre-sleep protocol mentioned earlier, you can enhance this cardiovascular conditioning even more when your sauna is combined with alternating sessions into a cool shower, a quick dip into a cold pool or lake, or if you’re lazy like me, a step into your backyard to shower yourself down with a garden hose. Each time you rapidly change temperature (from hot to cool or vice-versa), your heart rate increases by as much as 60%, which is very comparable to the heart rate increase experienced during moderate exercise. And in case you’ve heard the rumors: yes, many folks find this to be a potent treatment for hangovers too.
- Increased Stress Resilience
There’s a good reason that best-selling author Nassim Taleb recommends environmental stressors as a way to become more “Antifragile”. As mentioned earlier, multiple research studies have shown that hyperthermia conditioning via the use of a sauna can prevent protein degradation and muscle loss by triggering the production of heat shock proteins (HSPs), which are then used by your cells to counteract potentially harmful stimulus, including environmental stress from pollutants, toxins, heat, cold, exercise stress and more.
Whenever a cell is exposed to an unfriendly environment, your DNA “separates” in specific regions and begins to read the genetic code to produce new stress proteins, including these HSPs. What this means is that exposure to sauna heat can induce a hormetic response (a protective stress response), which promotes the production of HSPs that are crucial to stress resistance, prevention of free radical damage, support of cellular antioxidant capacity and repair of damaged proteins. Dr. Rhonda Patrick talks about these HSPs quite a bit in our podcast episode on heat therapy and saunas.