The Myth of Sweating Toxins
Does your yoga instructor tell you that the sweating is good for you because you are releasing toxins from the body? Well, this statement is not 100% true. Most of what you are sweating is water, but there are other chemicals that make up sweat including salt, potassium, ammonia, and urea. True toxin elimination comes from the kidneys and liver, and some from the colon. Doing a ninety-minute hot yoga session and sweating to death is not releasing toxins. You really are just dehydrating yourself and losing only water weight. I hate the burst the bubble, but my statement is true to the facts of body’s biological systems. If you really want to eliminate toxins from the body, it’s best to talk to your physician or purchase an over-the-counter liver, kidney, or colon cleanse made out of natural ingredients.
The Myth of Flexibility
There is a difference from muscular flexibility and joint flexibility. Your ligaments and tendons don’t get much blood flow, especially your ligaments. The reason for this is because your ligaments are in place to stabilize the joints. When you are in a heated environment, your blood flow increases making you feel like you are more flexible then you really are.
Being in intense postures like virasana (pictured to the right) may be more difficult if the studio is unheated because your joints give a stoppage point in the knees, whereas when its heated, you may not feel that stoppage point and surpass your safe zone. Ligaments do have some stretch to them, but not a lot. The more you continue to stretch your ligaments in joint-heavy poses, the higher your risk for tearing a ligament, or stretching them to the point where your joints are not as supported. It’s important to understand that when ligaments stretch out they stay that way and cause joint instability.
Everyone assumes that yoga is good for rehabbing, but understand that yoga is simply another form of moderate exercise and you can still injure yourself. I personally believe that some yoga instructors do not receive enough training in kinesiology or anatomy and physiology to keep people safe, and if you add the heated element into the mix, it does have the potential to be disastrous – especially if someone is new to yoga all together. Understand, this is not to say all yoga instructors are this way. There are many excellent yoga instructors who teach in a heated environment and keep students safe, and if a student is showing signs of heat exhaustion the instructor immediately cares for the student. But unfortunately, not all yoga instructors are created equal.
For all of you athletes, keep yourself safe. Walk out if it’s too damn hot. Don’t surpass your sticking point. And lastly, do your homework. Find a yoga studio and instructor that are right for you.
Hot yoga is done at room temperatures between 90° and 105°F (sometimes even higher), with humidity between 40 and 60 percent. During a typical class, which can last up to 90 minutes, you move through a series of linked flowing poses. Even for fit young people, hot yoga is a grueling practice, famed for leaving puddles of sweat behind.
Practitioners say that hot yoga will improve both mental and physical health—that it will enhance mental clarity and concentration, increase flexibility, build strength, promote weight loss, flush toxins, make skin look better, ease back problems, and even cure asthma, heart disease, and other ailments. But does it really have such benefits and, more important, is it a safe way to practice yoga? Will it leave you feeling energized and invigorated—or lightheaded and irritable? Is hotter better?
There has been little published research on the health benefits and risks of hot yoga and none comparing it to other forms of yoga. A 2011 study in the Journal of Exercise Science and Fitness found that Bikram yoga (at least 20 sessions over eight weeks) increased mindfulness, lowered perceived stress, and improved balance and flexibility. And a small study in 2013 in the Journal of Bodywork & Movement Therapies found that middle-aged obese people who did Bikram yoga for eight weeks had improvements in glucose tolerance, with no adverse effects. On the other hand, a study in the Journal of Exercise Physiology in 2012 concluded that “Bikram yoga training has no effect on pulmonary function or maximal aerobic capacity”—not surprising, actually, since yoga is not typically done as a cardio workout.
What about claims that hot yoga improves flexibility more than other types of yoga? Sure, heat warms you up, so you may be able to get a better stretch compared to stretching in the cold. But this could also make it easier to overstretch and injure yourself. Is it true that hot yoga will cleanse your body of toxins through sweating? The idea that sweating will “detoxify” the body lacks any basis in science. Though some toxins are eliminated through perspiration, the vast majority are processed by the liver and eventually excreted through urine and stool, not sweat.
The safety of hot yoga depends on your fitness level and overall health, among other factors. But exercising in extreme heat can lead to dehydration and hyperthermia (elevated body temperature), both of which can cause nausea, dizziness, fainting, muscle cramping, and other symptoms. And if you become very dehydrated and drink too much water afterward without consuming electrolytes, you run the risk of developing hyponatremia (low blood sodium levels), which can also cause such symptoms as nausea and muscle cramping, along with general malaise and even seizures. That’s what happened to a 34-year-old woman who was hospitalized after she did a 90-minute hot yoga workout and then drank 3.5 liters of water, as was reported in the British Medical Journal Case Reports in 2012.
Then there is the stress that the heat, especially in combination with exercise, can put on the cardiovascular system. If you’re unfit or have been sedentary, or have hypertension or heart disease, for instance, you should not be doing hot yoga. The authors of a 2013 paper in PLOS ONE cautioned that hot yoga may be inappropriate for older adults and people with medical conditions in general.
Hot yoga has risks. If you are physically fit and healthy—or otherwise have gotten your doctor’s okay—you can try it, but heed the following advice, which applies to all yoga training, especially more strenuous classes. Make sure the class is taught by a qualified instructor (certified Bikram instructors have nine weeks of formal training). Don’t work out beyond your capacity (it’s not a competition, even if some classes make it seem that way). Stop if you get lightheaded or begin to feel unwell in any way.
Bring your own mat that provides good traction. And stay well-hydrated (drink at least two hours before class and even during class). Plain water is fine for most workouts (just don’t drink to excess). For classes lasting longer than an hour, a sports drink is good for replacing electrolytes like sodium that are lost in sweat.
Do not do hot yoga, however, if you have high blood pressure or a heart condition or are pregnant. Keep in mind also that other styles of yoga likely have the same psychological and physical benefits as hot yoga, without the added physical stress and risks associated with exercising in extreme heat. Lastly, don’t believe claims made by practitioners that hot yoga will cure heart disease, asthma, or other chronic illnesses.
Hot yoga is a hot trend in the practice these days. Almost every studio offers a hot class of some variety, from Bikram to Moksha, vinyasa to yin. (One of the studio owners I work for confessed to me that she doesn’t like or believe in hot yoga, but it’s what students have requested.) And in summertime, almost every yoga practice can feel like a hot one.
Advocates say hot yoga facilitates stretching, increases range of motion, removes toxins, and promotes weight loss. It’s true that it is easier to stretch warm muscles (and you should never stretch “cold” muscles), but whether hot yoga will lead to greater weight loss depends on the type of yoga you’re practicing.
According to the American Council on Exercise, Hatha yoga (in the West, this has come to refer to slower-paced classes) burns about 150 calories an hour (and does not raise your heart rate enough to be considered a form of cardio), while vinyasa (faster-paced, flowing yoga) burns about twice that much. If you’re losing pounds after each hot yoga class, it’s likely water weight. (More on that later.)
Whether you practice naturally hot yoga as I do or practice at a studio that cranks up the heat, you’ll want to be safe. (You might also want to read: “I Tried Hot Yoga” before you take a class.) Here are some tips to help: Be safe. Decide if it’s right for you. Hot yoga is unsafe for anyone who is pregnant, a child, over the age of 60 (without a regular yoga practice), or suffering from medical conditions that would make it unsafe to exercise. If you have diabetes, any issues with high or low blood pressure, or are prone to dizzy spells, choose another type of yoga class.
Though it seems counterintuitive to shower before a workout, You may often rinse off before yoga practice to remove any lotions or oils that will make your skin even more slippery once your body starts to sweat. There’s nothing more frustrating than finally nailing an arm balance, only to slide right out of it because of lotioned-up skin! (Also: skip the scents. The only thing worse than being stuck on a mat next to a stinky person is practicing on a mat next to a person who’s drenched in perfume or cologne. Re-apply deodorant before class if you’re self-conscious, but skip the perfume, the smell of which can be overwhelming in heated, humid rooms.)
Invest in a chamois or a yoga towel. All that sweat turns your usually sticky yoga mat into a slip-and-slide. While you can use a regular towel (try a beach towel for maximum coverage), if you practice regularly, consider investing in a yoga towel, which is made of micro fibers that absorb moisture and become grippy when wet. Some also have silicone beads for added stickiness. A travel yoga mat, such as those from Gaiam, also works well as a mat cover. Take a hand towel, too, if your studio doesn’t provide them. In addition to mopping sweaty brows, a quick swipe of the towel up and down your limbs can make many poses more manageable.
Respect your edge. In yoga, encourage performing women to relax and let their bodies ease into a pose. When our muscles are warm, it’s easier to stretch them, which means that suddenly body parts find it a little easier to say “How do you do?” Knees meet nose, fingertips touch toes, and arms clasp behind the back with more ease when you’re warm. Whether you’re trying to bind in twisting pose or just reach a centimeter farther in a forward fold, don’t push too hard. Move slowly and mindfully to a point where your muscles feel challenged, breathing all the while! Never stretch to the point of pain–and never bounce as you stretch.
Take a rest. If you feel lightheaded, dizzy or otherwise ill at any point during the practice, take a break. Sit down on your mat, go into child’s pose, or step out of the room. (Note:
Some teachers lock the door or refuse to let students leave the room after class has begun. While it is not good manners to saunter in and out of a yoga studio during class, when you’re sick or really need to use the bathroom, it’s fine to leave–just be discreet. Sure, you might let a little heat escape the room, but passing out in the middle of tree pose would surely cause a bigger interruption!)
Drink up. In yoga, you should traditionally drink water before and especially after a class. The traditional belief is that our yoga practice builds heat, and water extinguishes it. Some hot yoga classes have designated water breaks, and I’ve heard stories of yoga teachers who scold students for even looking at their water bottles during class. While you might not want to chug water after every sun salutation, a few sips of water as needed are fine. Save the water guzzling for after class, if only because you’ll feel uncomfortable trying to twist and stretch with a belly of water. And trying to practice yoga with a full bladder? Uncomfortable! Drink one to two cups of water 30 to 60 minutes before practice, then…
Keep drinking. You lose as much as 32 ounces of water for every 60 minutes of exercise. Immediately after exercise, drink at least twice that much–especially if you’ve not been drinking much water during your yoga practice. If your practice lasted more than an hour, consider consuming a sports drink in addition to regular water to replenish carbohydrates and electrolytes. Note: If you feel lightheaded or uncoordinated (more than usual!) or have muscle cramps, consider these to be signs of dehydration.
Eat right. As with any physical activity, you’ll want to make sure you’re eating right to help you perform your best. While a snack or light meal an hour or so before working out is recommended, you might want to allow two hours between any snacks and four meals between any heavy meals and your yoga practice. If you thought practicing with a belly full of water was uncomfortable, try practicing with a belly full of food. Ugh! And if you can, save foods that are spicy or those that tend to give you gas or cause bloating for after class. You’ll want to eat a snack or meal that contains both protein and carbohydrates within an hour of finishing your practice.
Listen to your body. Only you know how far you can comfortably push your body. Listen to those signs that your body offers you. Don’t feel the need to “keep going” in a pose if the intro level is enough of a stretch and challenge for you. Your yoga practice is yours and yours alone. Quiet the ego–that little voice that tells you to push harder when you know you could risk injury–and just breathe and enjoy being where you are now.
Dress for it. Hot yoga is not the time to be modest. No one is there to judge you, and no one looks his or her best when dripping in sweat. Wear tight-fitting clothes, as looser garments trap heat. Some people prefer to wear pants or capris so they absorb the sweat and keep it off your mat; You should much rather have the sweat on my mat than have sweaty clothes covering any more of my body than is necessary! Tank tops are a great choice, as they allow for better range of motion and generally stay in place better than a T-shirt. It is highly advised to you against wearing regular cotton clothing. Once drenched in sweat, it will feel heavy and clammy against your skin. A moisture-wicking headband (I like Bondi Bands) is a must for keeping sweat from dripping in your eyes. That’s a surefire way to break your concentration!
Whether you’re doing yoga in a heated studio or in the great outdoors, these tips can ensure a safe and comfortable practice.Hot yoga devotee Karla Walsh feels exhilarated after an hour of twisting her soggy limbs into pretzel shapes, but the Iowa-based writer wonders if all that swelter really ramps up her workout. Bikram and other types of hot yoga, where temperatures can soar to 105 Fahrenheit (40.5 Celsius) or higher, are increasingly popular. Fitness experts say the hot-house workout if done properly is not harmful and may seem more challenging, but add that followers aren’t working any harder than in other yoga classes.
“The benefits are largely perceptual,” said Dr. Cedric Bryant, the chief science officer of the American Council on Exercise (ACE). “People think the degree of sweat is the quality of the workout, but that’s not reality. It doesn’t correlate to burning more calories.”
In a small study sponsored by ACE at the University of Wisconsin-La Crosse, researchers who monitored two dozen healthy adults during regular and hot yoga classes found no difference in the increase in core temperature or heart rate between the two 60-minute sessions. “An increase in core temperature would suggest the person is storing heat, and depending on how high, would be at risk for heat injury,” Bryant explained. “We didn’t find that.”
He added that people enjoy hot yoga because it allows them to feel more flexible. “But as far as physical benefits,” which he said include muscular strength, endurance, flexibility and balance, “you can get those from a standard yoga class.”
For the study, the hot yoga was conducted in an average temperature of 92 degrees Fahrenheit (33 Celsius). Bryant said in classes, including the popular Bikram style, where the temperature rises to 105 Fahrenheit (40.5 Celsius) or higher, further study is needed. “Many folks want to know what happens in that really extreme class,” he said. “Our study says you don’t have to be at those extreme temperatures to get all those benefits.”
New York-based yoga instructor Taj Harris likens a hot yoga class to a physical therapy session with heat packs or a massage with hot stones. “The heat allows the body to be more supple,” said Harris, who teaches 60-, 75- and 90-minute classes at Crunch fitness centers. “It increases joint lubrication as well as flexibility in muscles.”
Harris said the heat, which can range from 92 (33 Celsius) to 100 (38 Celsius) degrees Fahrenheit in her classes, eliminates the need for the extended warm-up of a traditional class. “People like to sweat, they enjoy the way their body feels after a nice heated stretch,” she said. “I have had the pleasure of watching some students work through tightness, strains and pains with a regular hot yoga practice.”
Harris encourages her yogis to drink water during class, bring plenty of towels to wipe away their excess sweat, and tells them that if they need a respite, it’s always cooler on the floor. Bryant said when doing any activity in a hot environment it’s crucial to maintain hydration and to watch out for early danger signs. “Dizziness, headache, lightheadedness, mild nausea and muscle cramps, are indicators that you’re not tolerating that heat,” he explained. “You need to remove yourself from that environment and get into air
Walsh said at first she didn’t get the whole hot trend, but now she is a fan. She credits it with helping her acclimate to the steamy Midwestern summer. “It doesn’t feel quite as daunting walking to work,” she said. Hot yoga, usually practiced in a room heated to between 90 and 105 degrees F, has been steadily growing in popularity, but the jury’s been out on it’s safety…until now. A recent study published by the American Council on Exercise finds that with proper hydration, hot yoga is just as safe as its less sweaty counterpart. University of Wisconsin-La Crosse researchers recruited 20 healthy, relatively fit people between the ages of 19 and 44 and measured their core body temperatures after a 60-minute Vinyasa yoga class in a 70-degree F room, and then again after another class where the temperature was jacked up to between 90 and 95 degrees F with 35% to 40% humidity.
Surprisingly, no difference between the core body temperatures after the two classes was found. After both, the student’s core temperatures rose to an average of 99 degrees, well below the unsafe 104 degree level when you start seeing trouble, says John Porcari, PhD, an exercise and sports science professor at UW-Lacrosse and one of the study authors.
“When you’re exercising it’s almost like your body shuts down if you get to that level,” he says. “It’s considered dangerous, and heat related illness is almost impending.” Dr. Porcari says the results were likely similar because the participants were well hydrated. The yoga teachers encouraged students to drink plenty of water before and during class.
“If you go into the class dehydrated or don’t drink during the class there is potential for problems,” says Dr. Porcari. He suggests starting to hydrate at least 30 minutes before a class, drinking 6 to 8 ounces of water immediately before class, and more as necessary during class.
He says another study would need to be done to test the safety of Bikram yoga, a popular and very regimented, 90-minute practice where students hold 26 poses in a 105-degree room. It was Tough Mudder that brought me back to yoga. Last October, I was trying to get back in shape to run the popular obstacle race, but after almost a year without exercising consistently, I didn’t know where to start. Turns out it’s hard to tell your body that you’re going to cut out Hot Cheetos and try to regain definition in your abs. I decided to start small by taking a yoga class.
I had tried yoga before, but it had been a while. After doing some research, I decided to enroll in Bikram, a type of Hatha yoga that involves doing 26 different poses in a room heated to 105 degrees. Maybe, I thought, it could help me get my training started. At the very least, it sounded entertaining.
Former Indian yoga champion Bikram Choudhury developed his brand in the early 1970s after moving to California and founding his own studio. His special practice of yoga quickly became famous, as celebrities such as Madonna and Kobe Bryant took it up. By 2006, he had 1,650 studios around the world. Increased popularity should attract increased scrutiny, but in many cases the yoga industry, and Bikram in particular, has escaped such vigilance. Instructors in classrooms around the world continue to portray yoga as a practice of whole body-mind healing without strong skepticism on the part of consumers. “If you know that a pursuit is as popular as Bikram yoga is and they give no disclaimer, would you assume it was dangerous?” asks Tali van Sunder, a writer for BeingHealthy.TV who has reported on the potential dangers of Bikram. “People just follow everyone else, especially if they want to believe what you are selling.”
According to Keith Baar, a biology professor at the University of California-Davis and an amateur yogi, my teacher’s statements about numbness being my body’s way of thanking me were an example of “yoga physiology,” the myriad of physiologically incorrect proverbs spit out by yoga instructors in their classes. This is a nice way of saying that it’s crap. Even some of the more mild physiological claims made by Bikram yoga can be disproved by basic knowledge of human body systems. My teacher kept telling my class that all the sweating we were doing was helping our bodies flush out toxins. Baar said this idea was “unfounded.” Your liver and kidneys do most of the detoxification in your body, and the toxins they clean out are excreted when you use the restroom, not when you sweat.
There is little awareness when it comes to the risks inherent in practicing yoga. When it comes to scientific research on the benefits of Bikram yoga, there is almost no data available. Its website lists a pair of studies that purport to support their claims. One is from The Journal of Strength and Conditioning Research and the other from a journal called Chinese Medicine. Neither specifically mentions Bikram yoga.
When it comes to information, we’re almost completely reliant on our teachers. Unfortunately, not all of them teach yoga in a safe way, and many lack strong practical knowledge of kinesiology. Instructor and Yoga Journal contributor Roger Cole has advocated for more awareness of how yoga can hurt the body as well as heal it. “Teachers often insist you push yourself further,” he says. “Mostly they are trying to show you that you can stretch further, but a lot of people don’t know what’s safe or not. A lot of people will stop at a certain point, but some won’t.”
The most dangerous part of yoga, then, is not the risk of the practice itself, but the dangers of the mind. What we suffer from is a large ego. When I show up to class I am always pushing myself further based on the people I see around me. If I can’t bird-of-paradise-with-a-bind better than you, I’m not satisfied.
Baar feels that can be the biggest problem. “People are competitive by nature, and in yoga classes people become competitive even though that’s not what it’s about,” he says.
Combined with a lack of bodily awareness, this can lead a novice yogi to discomfort and even injury. Van Sunder says she doesn’t think Bikram was too dangerous for everyone, but that based on her research, the benefits were no greater, and the hazards significantly worse, than in normal, unheated yoga.
It seems strange that Bikram can get away with barely any questions asked. Of course, I’m not the first person to feel this way. New York Times writer William Broad, author of The Science of Yoga: The Risks and the Rewards, also investigated the potential dangers that can be caused by yoga. In an interview, he discussed how yoga’s marketing has done a fabulous job of skirting mention of its risks.
“The yoga industrial complex has an economic incentive to look the other way,” he says. Broad’s article was criticized by many in the yoga community, who felt that their students were savvier than Broad gave them credit for. Broad, on the other had, said he had regularly seen students pop ribs out of place. Another writer on yoga culture, Benjamin Lorr, said that hallucinations and blackouts were common, and he had even seen someone suffer a mild stroke.
What both sides seem to agree on is that the safety of yoga practice relies on the awareness of the practitioner. The increased popularity of yoga has brought in thousands of students who are not in good enough condition to be taking on the challenging practices. As a teacher, Roger Cole sees some of them come into his class. While yoga can be great for the average athlete, many of the less-experienced people now taking it up don’t know their own bodies well enough to be able to tell when to call it quits.
“The average person still doesn’t know the risks. If you get a friend’s referral, you will go blindly,” Cole says. “People give up power to their teacher. You should always question what’s right for you.” Bikram yoga, the original hot yoga, is known for its “no pain, no gain” stance, with founder Bikram Choudhury referring to his classes as “torture chambers.” If you have a tendency to get competitive or ignore your body’s signals, this might not be the best environment for you. Overstretching your muscles can also lead to injury, so being in an environment that makes you feel hyper-flexible requires diligence and patience to keep yourself safe. If you don’t drink enough water, you could suffer from dehydration, so up your water intake if you plan to start a regular hot yoga practice.
Women Fitness has been able to provide a scientific reasoning about risks associated with performing ‘hot yoga’ and how to be aware about them and what practices to follow to reduce these risks.