Saunas are a hot topic lately—pun intended—but they’ve been a staple in Nordic cultures for thousands of years, celebrated for their wide-ranging health benefits.
Health Benefits of Sauna Use
Sauna bathing offers a long list of health benefits, including:
- Lower blood pressure
- Reduced risk of cardiovascular disease
- Improved lung function
- Decreased frequency of common colds
- Pain relief
- Enhanced mental well-being
These benefits stem from the body’s adaptations to heat exposure. When exposed to high temperatures, the body increases blood volume by increasing plasma volume (the water in blood). Hormonal changes also occur—such as elevated cortisol and growth hormone levels—helping the body better tolerate heat. These responses are regulated by the sympathetic nervous system (SNS), our “fight or flight” mechanism. Over time, this heat stress conditioning can improve the body’s ability to handle other physical and mental stressors.
Sauna use also promotes the release of endorphins—our natural “feel-good” chemicals—and provides a space for mindfulness and relaxation, offering a much-needed break from our busy lives.
“Sauna Fitness”: A Workout Without Moving
The term sauna fitness is used in research to describe the physiological changes that occur with regular sauna use—many of which mirror those seen with exercise. For example, one study found that athletes who used a sauna daily for four days after exercise experienced increased plasma volume. Without sauna use, their levels returned to baseline within a week.
Other adaptations include a reduced rise in core temperature during heat exposure, a sign of heat acclimation. These cardiovascular changes may also enhance aerobic capacity—your body’s ability to use oxygen efficiently during prolonged activity—ultimately boosting athletic performance.
Infrared vs. Finnish Saunas
There are two main types of saunas, each with unique characteristics:
- Infrared Saunas:
- Temperature: 110–140°F
- Uses infrared light to heat the body directly
- Dry heat, more comfortable for longer sessions
- Promotes recovery and relaxation, especially after endurance exercise
- Finnish (Traditional) Saunas:
- Temperature: 180–190°F
- Uses heated stones, often with steam
- More intense cardiovascular stimulation
- Better for heat acclimation and cardiovascular adaptations
What About Hot Tubs?
Good news—if you don’t have access to a sauna, hot water immersion (HWI), such as soaking in a hot tub, can offer similar benefits. In some cases, HWI may even lead to greater increases in core temperature and cardiovascular adaptations than sauna use. For athletes, HWI can aid in recovery and help prevent muscle cell damage after exercise.
Environmental Heat vs. Controlled Heat Exposure
Our bodies respond similarly to heat stress from saunas, hot tubs, and environmental heat. All forms of heat exposure trigger cardiovascular and hormonal adaptations that can enhance performance. However, environmental heat can be unpredictable and potentially dangerous, especially during intense exercise or in high humidity.
In contrast, saunas and hot tubs offer a controlled and relaxing environment. They can also be used year-round—even in cooler climates—to maintain the benefits of heat exposure.
Final Thoughts
While saunas have been used for centuries, modern research is still uncovering the exact mechanisms behind their health benefits. There’s also limited data on how sauna use affects athletic performance across different sports and training levels. More studies are needed to determine optimal timing and protocols.
That said, the existing evidence supports a wide range of health benefits from sauna use and hot water immersion. Whether you’re looking to boost recovery, improve cardiovascular health, or simply unwind, taking time to heat things up might be just what your body—and mind—needs.
