It may not be the number one thing you want to think about in the middle of a summer heatwave, but let's talk saunas — and specifically, whether saunas have any significant post-workout benefits. Maybe you've seen people heading into your gym's sauna after a workout but never really understood why, or maybe you just want to know why people would want to follow up a sweat session with . . . another sweat session. You've come to the right place, but first, let's cover some background info.
There are a few different kinds of saunas, but the main ones you hear about are the traditional sauna, which heats up the air and increases humidity to produce sweat, and the infrared sauna, which heats your skin directly (without as much ambient temperature change) by using infrared lamps that generate electromagnetic radiation. Since the infrared sauna is more targeted, the temperature in infrared saunas is significantly lower than that of traditional saunas. They range from 120 to 140˚F, whereas traditional saunas are more like 150 to 180˚F. Both types come with post-workout benefits, but keep in mind that infrared saunas are newer and not as well-researched as traditional saunas.
Should you use a sauna — whether infrared or traditional — after your next workout? And what should you know before going into the (very sweaty) experience? (Hint: hydration will be key.) POPSUGAR spoke to two experts to get the scoop on sweating safely in a post-workout sauna sesh.
Sauna Benefits After a Workout
Using a sauna after a workout can be beneficial, but it's not as straightforward as you'd think. According to experts and research, post-workout sauna use can:
- Improve heat tolerance: Research shows that using a traditional sauna can improve your body's reaction to heat, which can be beneficial if you often work out in hot conditions. "When you head into the sauna, your body will respond as expected by sending blood to your skin to help you sweat and avoid overheating," explains exercise physiologist Stacy Sims, PhD. Your body's blood flow will already be slightly limited due to dehydration from your workout, so combining that with the increased temperature in a sauna creates "a strong survival stimulus to improve your body's ability to handle the heat," Dr. Sims says. With consistent post-workout sauna use, she says, your body will be pushed to start sweating earlier. That's a good thing for athletes because sweating helps you maintain optimal body temperature and function when it's hot out.
- Boost workout performance: Post-exercise traditional sauna use can also improve workout performance overall, likely because saunas help increase blood flow, a 2007 study notes. Sauna use helps to "increase both red cells, which increases your body's ability to carry and deliver oxygen to working muscles, and plasma volume, which boosts your blood volume and subsequent performance," Dr. Sims says. ACE-certified personal trainer Stephanie Thomas adds, "When used a few times a week post-workout, [saunas] can help you improve your endurance and simply feel stronger during your workouts." A 2015 study notes that using an infrared sauna with a mild temperature (95 to 122°F) and light humidity (25 to 35 percent) "appears favorable for the neuromuscular system" and can help athletes recover from maximal endurance performance.
- Relieve joint pain and muscle soreness: Since the heat of a traditional sauna will relax and dilate your blood vessels, it may help loosen up stiff muscles and joints after a workout. For infrared saunas, a 2009 study showed that sauna sessions improved pain, stiffness, and fatigue for people with chronic musculoskeletal diseases, including rheumatoid arthritis.
- Relax your mind and body: Yes, it's sweaty and hot in there, but saunas are also designed to be very relaxing — which is a major reason people love them. For example, a 2019 survey of 482 people from the US, Finland, and Australia found that using a sauna five to 15 times per month was associated with high "mental well-being." A 2018 review, meanwhile, notes that using the sauna causes your body to release endorphins and other feel-good chemicals, as well as results in a state of "forced mindfulness" and relaxation that can lead to real psychological benefits — all especially pleasant additions to your post-workout routine. Using a sauna is "an amazing way to relax your body and mind after a tough workout session," Thomas confirms.
While there's plenty of research supporting post-workout sauna use for improved performance and heat tolerance, a 2019 study showed that those effects might not always hold true. The small study found that, in a group of 20 swimmers, athletes who used a sauna directly after a training session performed "significantly worse" in performance tests the next day.
While saunas do relax your body and mind, they also put your body under a certain amount of stress — otherwise, it would have no reason to adapt and improve its athletic performance and heat tolerance. That stress, as the 2019 study shows, can cause some less-than-desirable effects as your body adjusts. As the study authors note, "coaches and athletes should be careful with postexercise [sauna use] if high-intensity training and/or competitions are scheduled on the following day."
