Is It Unhealthy to Use a Sauna After a Workout?

Many health clubs and fitness centers offer saunas to help members relax and unwind after exercising. The dry heat of a sauna offers many health benefits when used safely, but can cause serious harm as well.

As long as you take proper precautions and keep hydrated, using a sauna after a workout can be both safe and soothing.

A typical sauna is heated to a temperature of 90 degrees Fahrenheit at foot level and 185 degrees at the top of the room according to Harvard Health. It's a dry heat with humidity levels hovering around 10 to 20 percent.

Depending on how reputable the sauna, the air circulates three to eight times an hour. The University of Wisconsin School of Public Health says that performing exercise and using a sauna afterward can help you relax and soothe sore muscles from your workout.

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A commonly held belief about saunas is that sitting in them will help you lose weight. While it may seem logical that raising your body temperature can melt away fat, it is not the case.

If you notice a drop in your weight after sitting in a sauna, you're probably noticing a loss of water weight from sweating. As soon as you replenish the liquids in your body, you'll gain the weight back.

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In a sauna, your body sweats as a way to cool itself and maintain a steady core temperature. The longer you stay in a sauna, the more water you lose. If you've already been sweating from your workout, a sauna can cause you to become dehydrated quickly. As you lose water through sweating, your blood vessels dilate and your blood pressure drops.

After a while, your body can no longer cool itself properly, and your internal temperature will begin to rise. According to the North American Sauna Society, some athletes have used a sauna to rapidly lose weight through sweating which has lead to heat stroke in some and unfortunate sudden cardiac deaths in others.

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Drink plenty of water after exercising and before getting in the sauna to prevent dehydration. Give your body time to cool off from your workout before entering, and spend 15 minutes at most in the heat.

Leave right away if you begin to feel dizzy or nauseated, and only use the sauna with other people present in case you become overheated and need assistance. If using a public sauna, wear shower shoes and bring a towel to prevent exposure to fungal infection.

In a review of the health benefits of sauna bathing, Mayo Clinic determined that having a sauna may be beneficial for people with stable cardiovascular disease.

However, people who are pregnant, have heart disease, uncontrolled hypertension or epilepsy or who are taking antibiotics, stimulants or tranquilizers should not use a sauna unless they get the go ahead from their doctor. And at no time is it advisable to use a sauna while under the influence of alcohol.