Why your sauna's temperature isn't what matters most

Heat therapy and thermoregulation

The body's optimal core temperature normally sits around 37°C. As soon as it starts to rise, your body activates several defence mechanisms: blood vessels dilate, skin pores open, heart rate increases and you start to sweat. This process is called thermoregulation: the body wants to cool down in order to return to its optimal temperature.

During heat therapy, you give your body a controlled heat stimulus, causing your core temperature to rise temporarily by roughly 0.5 to 1.5°C. Through thermoregulation, your body then tries to cool itself down, which places a significant demand on your cardiovascular circulation. Heat therapy is therefore a form of cardiovascular training stimulus, without you having to exercise.

Heating the environment isn't the same as heating your body

Heat therapy only works if your core temperature rises. So it's not about the temperature of the environment. You can make your skin extremely hot without your core temperature rising sufficiently. And conversely, a milder, more comfortable environment can raise your core temperature just as well, as long as you can stay in it long enough.

Research confirms this difference clearly:

• Hot water bath (40 to 41°C, 45 minutes): highly efficient, core temperature rises by an average of 1.1°C. But you can't sweat underwater, so your cooling mechanism can't function. Your body has little ability to control how quickly it loses heat, which makes the thermal load high.
• Finnish sauna (80 to 100°C, short blocks): air transfers heat far less efficiently than water, which is why your body can only tolerate these high temperatures for a limited time. In a Finnish sauna, skin temperature can reach 40 to 41°C (which is why sessions are broken into short blocks with cooling periods in between). Recent studies show that after 30 minutes, core temperature rises by approximately 0.9°C. However, the average Finnish sauna session lasts only 5 to 20 minutes because of the high skin temperature. Effective, then, but not practical for many people.
• Full-spectrum sauna: combines different infrared wavelengths (link to the relevant EN article, if available, needed here), including short-wave infrared. These carry a lot of energy but mainly heat the skin (think of a patio heater). Raising your core temperature would require sitting in front of a full-spectrum emitter for longer than 15 minutes. However, the general recommendation is to sit for no more than 10 to 15 minutes.
• Carbon panel heaters: feel comfortable and warm the skin, but in a recent study directly comparing this method to a traditional Finnish sauna, core temperature barely rose at all after 45 minutes. Pleasantly warm, but it doesn't build up thermal load.

The Health Mate approach

In a Health Mate infrared sauna, what matters isn't your skin temperature but your core temperature. We aim for a comfortable heat that lets you stay in the infrared cabin long enough for the warmth to build up throughout your entire body. To achieve this, we use our Tecoloy elements, which emit far-infrared at long wavelengths, readily absorbed by the water in your body. This creates a pleasant warmth that allows you to sit for 40 to 45 minutes. During a 45-minute session at 55°C, core temperature rises by roughly 0.9 to 1.2°C, comparable to a hot bath, but without the intensity of immersion or the heat of a Finnish sauna.

Discover our 3G method

Want to experience for yourself how long-wave infrared can work for you? Book an appointment for a trial session at one of our showrooms.

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