Thermotherapy or as it’s more colloquially known, heat therapy, is this season’s (literal) hottest health trend. Throughout history, heat has been a powerful health tool for increasing physical recovery.
Athletes historically use it to reduce post-workout soreness and to promote fat burning. And it’s been long prescribed by medical professionals to reduce pain and aid with recovery from injuries. But over the last few decades, as heat therapy has become more affordable and accessible, this health practice has gained mainstream popularity amongst biohackers and everyday folk looking to incorporate warm recovery into their health routine.
So in this article, I’ll dive into what exactly heat therapy is, how it works, the science behind how it helps with recovery, and how I use infrared sauna to access these health benefits from the comfort of my home.
What Is Heat Therapy?
Thermotherapy, or heat therapy, is any practice that uses heat to increase the temperature of the skin and/or internal soft tissues. It’s a practice that has been around since ancient times. From the hot baths of the ancient Romans to the Finnish invention of the sauna (1); both of which can be traced back thousands of years. And yes, a hot bath counts. So if you’ve ever taken a hot bath and felt great afterward, then you’ve had a taste of thermotherapy!
But there are many forms of heat therapy beyond just baths. Here are some of the different forms of heat therapy with specific examples:
- Dry heat therapy e.g. heat pads, dry sauna
- Wet heat therapy e.g. hot baths, steam rooms
- Infrared heat therapy e.g. infrared sauna and sauna blankets
- Electrotherapy e.g. high frequency ultrasound
Different types of thermotherapy come with slightly different benefits but they all deliver a hot mug of healthy goodness.
How Does Heat Therapy Work?
So we know about what heat therapy is, but how exactly does heat deliver any kind of health benefit? To understand this, we must first understand the effect of heat on our bodies.
There are many studies looking at the various effects of heat on blood flow, hormones, nerves, and organs. But these are too technical, long, and beyond the scope of this article. The simplest way to understand the effect of heat on the body is as follows:
- heat increases the temperature of the skin and internal organs to cause the widening of blood vessels. The scientific name for this is vasodilatation. Heat also causes your heart rate to rise.
- increased vasodilatation and heart rate results in more blood flow being delivered to tissues and joints. More blood flow = more oxygen and nutrients to damaged areas
- heat causes both a change and a rise in metabolic activity
- heat changes the way that nerve cells function, in particular, it can alter the firing of pain receptors.
Altogether these effects go a long way to explaining the general effects of heat on the body and how heat can help with physical recovery.
- more oxygen and nutrients in tissues and joints promote healing and loosen stiff joints and muscles (2)
- note: do not use heat when the joint is acutely inflamed, swollen, or bruised as this can make things worse
- increased metabolic activity will help with removing lactic acid from workouts which will reduce soreness (3)
- modulation of pain receptors reduces the pain associated with new and old injuries (4)
How Does Heat Have These Health Effects?
If we want to understand what happens on a deeper level, then we have to understand the concept of hormesis.
Just like cold therapy, the general driver behind the health benefits of heat is hormesis. Hormesis is the field of science that studies how small doses of potentially harmful substances, hormetic stressors, can result in positive health benefits.
Good hormetic stressors provide enough stress to force healthy adaptation (5), but not enough stress to harm you. AKA it hits the sweet spot of stress. This hormetic stress is the same stress that’s responsible for the health response with exercise or intermittent fasting.
So really all these body changes in response to heat are a hormetic effect. They are a response to heat stress. And just as with many things in life, overcoming stress leads to us becoming stronger in the long run. If you want to double up on your hormetic stress, grab an ice bath and take the plunge as well!
How Can I Access Heat Therapy From Home?
Image: Supplied by the author
So we’ve covered what heat therapy is and how it has positive health effects on physical recovery and healing, but what’s the best way of accessing these benefits from home?
The easiest and most cost-effective method is through:
- Heat pads on muscles/joints for local heat therapy
- Hot baths for full body heat therapy
However, my favorite method of doing at-home heat therapy is through an infrared sauna. Infrared is a newer form of heat therapy that uses infrared light to heat up the body directly and from within.
And don’t worry, it is not harmful. In fact, we produce low levels of infrared light ourselves!
The infrared light from these saunas can penetrate the skin to about 1.5-2 inches deep to directly heat tissues from inside the body. Because of this direct and deep heating effect, infrared saunas use lower heat temperatures, between 100˚F (38°C) and 167˚F (75°C), and are typically better tolerated. So theoretically you get fewer side effects and more health benefits!
So that’s it. I hope you’ve gained some insight into the world of heat therapy, some understanding of how it works at both the cellular and physiological level, and how you can use heat therapy at home to level up your recovery and wellness game. Enjoy sweating!