What if I told you one of the healthiest things you can do is subject yourself to temperature extremes? Studies show there are huge benefits to our health, well-being and longevity by either hanging out in a sauna, exposing ourselves to cold or better yet, doing both. Our ancestors had to deal with temperature extremes and many cultures still incorporate heat and cold into daily lives, think of American Indian Sweat Lodges or Finnish Sauna’s. What can we learn from these activities and what can we do to incorporate more thermal extremes into our daily lives?
If you live in an advanced economy, you probably lead a comfortable life. It’s very rare for you to be exposed to extreme temperatures. Your office, home and car are climate controlled. However, this is a relatively new phenomenon. From a biological stand point your body is used to being exposed to temperature extremes and it appears making ourselves too comfortable is not the best thing for body or mind. Though chronic stress is bad, it is a good idea to expose yourself to short bursts of stress to help your body activate stress adapting pathways and prepare for future stressors. This process is defined as Hormesis: “a biological phenomenon whereby a beneficial effect (improved health, stress tolerance, growth or longevity) results from exposure to low doses of an agent that is otherwise toxic or lethal when given at higher doses.” One of my favorite stressors is exercise, but for this post we will focus on passive stressors, e.g. cold showers, sauna’s, ice baths, etc.
Heat Stress
Muscle
Heat elevates our core body temperature and activates Heat Shock Proteins, which function as intra-cellular chaperones for other proteins. They play an important role in protein–protein interactions such as folding and assisting in the establishment of proper protein conformation (shape) and prevention of unwanted protein aggregation. Role of heat shock proteins. This means sauna helps reduce skeletal muscle catabolism (breakdown), which is very important as we age. According to WebMD, at some point in your 30s, you start to lose muscle mass and function. The cause is age-related sarcopenia or sarcopenia with aging. Physically inactive people can lose as much as 3% to 5% of their muscle mass each decade after age 30. Exercise is the best way to prevent muscle loss, but heat exposure is also beneficial. A Study on mice showed that those exposed to sauna increased their myocardial (heart muscle) protection by 30%.
Longevity
One of the longest and best documented studies on sauna exposure and longevity was conducted by Finnish cardiologist, Jari Laukkanen. He studied 2,315 middle-aged Finnish men for twenty years and discovered that those who did a twenty-minute sauna, four to seven times a week with a temperature of 174 degrees had a 40% reduction in all mortality compared to men who only used the sauna one time a week. Dr. Laukkanen’s study controlled for obesity, smoking, alcohol, cholesterol, Diabetes, physical activity and socio-economic status. Long term sauna use did the following:
- Lowered Blood Pressure
- Balanced the autonomic nervous system, which is the unconscious nervous system that controls our internal organs.
- Improved endothelium (cells that line our blood vessels) function.
Dr. Laukkanes is currently working on studies to determine the optimum sauna exposure dosage. He believes benefits could increase with exposure longer than 20 minutes as the increased heart rate from heat leads to myocardial stress adaptors (much like exercise). In the meantime, it appears 20 minutes on most days of the week is a good start.
Benefits of Cold Exposure
Increase Base Metabolic Rate
For my weight conscious and esthetically driven readers, cold exposure is a proven calorie burner. It takes a lot of energy to heat up your body. Cold increases your brown fat stores, which are dense with mitochondria, which make them a calorie burning powerhouse when compared to white adipose (fat) tissue. It used to thought that only babies had brown fat (to help keep them warm), but scientists have proven that adults still have some as well. And the good news is researchers have proven you can up your brown fat content by exposing yourself to cooler temps. The ICEMAN Study , directed by Endocrinologist Dr Paul Lee, aimed to determine if brown fat could be manipulated to grow or shrink. The study was small, only five healthy men who were exposed to four month-long periods of defined temperature. Results of the study showed that lowering temperature from 24 degrees to 19 degrees resulted in an increase of brown fat by around 30-40%. The reverse was also true as warmer temperatures decreased brown fat stores.
Brain Protection
It is also believed that cold is neuroprotective and may have benefits in combating Alzheimers. Old mice exposed to cold had less brain degeneration than their counterparts exposed to a more temperate climate. Mice Study: Cold Keeps Dementia Away
In addition, cold releases norepinephrine which is an anti-inflammatory agent that strengthens your brains synapses (communication) and can help you remember better. Take away tip: Try a cold shower before a stressful presentation, speech or test.
Boost Your Immune System
Studies have shown that cold exposure increases levels of circulating white blood cells (the cells that rid your body of nasty invaders) and natural killer T cell’s, also a key player in your body’s immune defenses. (Note: Killer T-Cells were discovered in 1973 and shout out to the researchers who came up with the bada$$ name.) http://www.physiology.org/doi/full/10.1152/jappl.1999.87.2.699. The study indicated this increase in white blood cells was heightened when cold exposure was preceded by exercise.
Assist in Recovery
Cold exposure is great for reducing inflammation. However, if your goal is hypertrophy or muscle adaption of some kind, I recommend you wait an hour before exposing yourself to cold as you will blunt the growth and adaption response provided from inflammation. In addition, if you are aiming to assist muscle recovery, as well as boosting immunity, I recommend cold water as you get extra benefits from water’s hydrostatic pressure, which is absent with an ice pack or cryo chamber. For example, I’m currently training for a marathon and after my long runs, I take a cool shower, eat and then go sit in 50-degree water. This gives my muscles time to get stronger from the activity without letting the inflammation outstay it’s welcome. I had my daughter video me taking a “plunge” in our unheated swimming pool in February. Me Taking a Cold Plunge
Conclusion
Remember when you feel uncomfortable for a short period of time, your brain will look to increase its “feel good” pathway. And let’s face it extreme heat or cold is uncomfortable, and potentially deadly. You should always have a physical to make sure you can withstand stress and to confirm you have no contraindications. If healthy, short bouts of thermal extremes will help make you more resilient to everyday stressors, such as an angry boss or disgruntled kids. So, get out there and make yourself uncomfortable! Take a cold shower, turn down the heat and turn up the air conditioner. Sweat and shiver your way to a leaner, healthier you.