Morey J. Kolber, PT, PhD. OCS, CSCS*D, TSAC-F, FNSCA
Firefighting is a tactical sport competing against heat, smoke, stress, unpredictable schedules, and the challenges of patient transfers. Every call pushes your body to its limits, and overall health is just as critical as readiness. What if there was a simple, time-tested tool to boost both health and fitness benefits? Enter the sauna, a centuries-old tradition that is making a comeback in performance and wellness circles.
Sauna use (whether classic Finnish dry sauna or infrared) works by exposing your body to high heat for short periods, often less than 30 minutes. This triggers mild hyperthermia, raising your core temperature and kicking off a cascade of physiological responses. Think of it as stress training for your cells as your cardiovascular system ramps up, hormones shift, and heat shock proteins go to work repairing and protecting muscle tissue. In fact, regular sauna use may improve thermoregulation. For firefighters, who face extreme heat on the job, these adaptations are critical. Translation? You are likely to stay sharp in high heat environments, fatigue less, and recover faster. Let us dive a bit deeper as the benefits do not stop here.
Flexibility might not be the first thing you think about when gearing up, but it is essential for injury prevention and performance on the job. Sauna heat relaxes muscles and increases tissue elasticity, making it easier to move and bend under load. Research shows measurable improvements in hamstring and shoulder flexibility after sauna sessions. Pair that with a functional movement program and you have a recipe for better mobility on the fireground.
Post-exercise sauna sessions increase plasma volume, which is a key factor for oxygen delivery during physically demanding work. In one study, competitive runners saw up to a 32% plasma volume increase and faster race times after three weeks of sauna use. For tactical athletes like firefighters, that means better stamina when the alarm sounds.
Muscle performance gets a boost too. Heat exposure activates pathways that promote muscle repair, growth, and strength while improving the rate of force development. One study even found that training in a sauna improved grip strength in both trained and untrained hands, which is important since grip strength predicts overall health.
Here is where it gets even more interesting. Frequent sauna use has been linked to lower blood pressure, improved cholesterol profiles, and reduced risk of cardiovascular disease. One 20-year study found that those who hit the sauna 4–7 times a week had a 40% lower risk of all-cause mortality. Furthermore, another study reported that using a sauna 3-7 times weekly was associated with a 16% lower risk of death from any cause after adjusting for risk factors.
Sauna has the ability to change your internal chemistry. Growth hormone (an anabolic hormone) spikes, cortisol (stress hormone) drops, and anti-inflammatory signaling molecules rise, creating an environment for repair and resilience. Heat shock proteins, your body’s cellular bodyguard, kick in to protect against stress and damage and are also valuable muscle growth/repair precursors. These benefits may help counteract the wear and tear of high-stress work and training demands while adding a boost to performance goals and recovery.
Exposure to carcinogens generated during the combustion of organic materials has been documented on the fireground. The measurement of polycyclic aromatic hydrocarbons (PAHs) has been used as a biomarker of firefighter exposure and reflects exposure from inhalation, skin exposure, and ingestion. While standard decontamination procedures have shown considerable reductions in exposure, an interest in additional measures such as sauna have been considered. In fact, some fire departments are providing saunas for use after returning from the fireground as a secondary measure of decontamination. The thought here is that some compounds may be more quickly eliminated by inducing a sweat response.
While research on sauna use for post-fireground detoxification is limited it is certainly not absent. One study evaluated the use of an infrared sauna after standard decontamination procedures (1). In this study, firefighters were randomly selected for sauna following standard decontamination procedures (e.g., cleaning their face, neck, hands, and arms with wipes soaked in a dish soap and water followed by a shower). Following the shower, about half of the firefighters completed 20 minutes at 120° F in the sauna and then showered once again. Results were favorable with the sauna and a second shower further decreasing (approximately 3%) PAH concentrations. A recent clinical trial on this topic was completed in Minnesota with results pending (stay tuned).
Infrared saunas, in particular, shine here. Research shows they reduce post-exercise muscle soreness and help restore neuromuscular performance after heavy training. For firefighters juggling intense physical demands and unpredictable schedules, faster recovery means less downtime and fewer injuries. In short, sauna use is likely to provide overall medium to long term recovery benefits.
One concern over sauna use is immediate recovery delays (2). While this may not be an issue following maximum stress exercise, it is important to consider following a high stress call. Essentially, the sympathetic (fight or flight) nervous system kicks into full gear while at the fireground or a high stress call (also during maximal exercise) as body temperature and heart rate rise. Following the termination of fireground activity, a high stress call, and heavy exercise we rely on our parasympathetic nervous system to reduce sympathetic input and cardiac stress. Given elevations in body temperature and heart rate during sauna use there may be a short delay in parasympathetic reactivation (recovery) until the sauna session is completed.
Before you crank up the heat, know the risks. Heart rate elevations and increases in body temperature do occur during use similar to low-intensity exercise, thus a cool down recovery phase is still required after sauna. Most sauna injuries come from slips or fainting, which is often linked to dehydration or alcohol. Stay hydrated during the session (**dehydration is not the goal**) and ease into sessions gradually. Start with 10–15 minutes at moderate temperatures and build up as your tolerance improves. If you have heart issues or other medical conditions, check with your physician first.
For firefighters, sauna use is not just a wellness trend, it is a performance tool backed by science that may have job-specific benefits. From better heat tolerance and endurance to faster overall recovery, improved hormonal response which includes reduced inflammation, and heart health, the benefits stack up. For more detailed information and a review of published studies see references below.
Exercise is not without its risks and this or any other exercise program many result in injury. As with any exercise program, if at any point during your workout you begin to feel faint, dizzy or have physical discomfort, you should stop immediately and consult a medical professional. You should rely on your own review, inquiry and assessment as to the accuracy of any information made available within this program or via this web site.