Q: I have been asked before regarding the difference/advantages/disadvantages to hot yoga; and I found your explanation very informative. Could you pass along some of the info from a factual/kinesiology standpoint to me to in turn pass along when asked?
A: I just had this conversation with someone in the gym, so here is my science-based perspective on WHY PEOPLE SHOULD BE CAUTIOUS AND INFORMED WHEN DOING HOT YOGA:
*ELASTIC EDGE – our muscles and connective have a finite elastic edge where, once you pass that edge, the tissues simply break (ie tears) … we have sensory mechanisms that help us feel when we are reaching this elastic edge to prevent injury … in hot yoga, the excessive heat can readily dampen these sensory mechanisms allowing us to pass our elastic edge and fall into acute injuries
*DETOXIFICATION – the claims that sweating detoxifies the body is an exaggeration … the liver, lymphatic system and kidneys are our dominant detoxifying mechanisms … the skin accounts for a very MINOR amount of potential detoxification … by dehydrating the body in hot yoga, we actually diminish the function of the major detoxification mechanisms leading to the next point
*DEHYDRATION – rapid dehydration (especially without correct preloading) depletes cells of intracellular water … all (I repeat, ALL) chemical reactions in the body function in a water state … dehydration via hot yoga can lead to reduced energy, constipation, adverse effects on metabolism, and other unwanted physiology effects like increased heart rate (next point)
*SYMPATHETIC NERVOUS REACTION – when we exercise (yoga), our body requires an increase in oxygen which is delivered via our heart and blood vessels … our CARDIAC OUTPUT (volume of blood x beats/min) increases to meet oxygen demands … however, by rapidly dehydrating the body (sweating), we pull water from the blood … blood volume goes down, so in order to maintain cardiac output, the heart has no choice but to increase beats/min … for me, the primary benefit of yoga is to tap into the parasympathetic nervous system as much as possible to heal, purge stress, and to restore … an increase in heart beat is brought forward by the sympathetic nervous system (our ‘fight or flight’ system) … given that people are already chronically stressed and sitting in constant states of sympathetic activity, this seems counterproductive
… staying on the sympathetic nervous reaction thought, I hear so often that people are encouraged to stay and sit through feelings of nausea – literally fighting the emergency response that the body is calling out to them … again, this is counterproductive to the healing nature we are trying to achieve in yoga … if you feel dizzy, nausea, faint, you are in a fight or flight state (near maximal levels) and could be causing damage to systems of the body
My take home message – know what you are getting yourself into – be mindful of biased claims by hot yoga studios and teachers – be bold in asking questions on those claims including ‘where is the science behind your claims’ – most of all, HOT YOGA IS NOT FOR BEGINNERS, it is an advanced form of practice and if a studio/teacher suggests it is ok for beginners, they are not looking out for the students’ best interest (ie just trying to make $) and/or are highly misinform
Kreg Weiss 
Reblogged this on StressMeKnot and commented:
Good to have extra information about Hot Yoga classes. I’ve not long started going to this style of class – I’ve only been a handful of times – but i’ve heard so many mixed messages about them…although I love my class, filling a small room with 4 strong heaters and 25 yoga learners of different levels is not ideal. Especially if they run back to back classes, bleurgh! I will be back though, I have never felt such a good cleanse after exercise…
Hello Kreg,
I am so pleased to read this article as I have also been asked many times what my views were on Hot Yoga. I have managed to provide a somewhat similar response in my own words and now thanks to your article, it will provide as mentioned in the initial question that lead to this article, factual standpoint and clarity when needed with regards of the caution that should be taken by anyone interested or curious about hot yoga.
Thank you very much for this very useful information and tool. Being knowledgeable about our body and its numerous system functionalities are incredibly important to increase the depth of awareness in one’s practice or teachings.
p.s. I look forward to meeting you in Dubai as I will attend your TT.
Thanks Andree,
I believe, regardless of yoga style, that there are potential contraindications that people should be made aware of. And when the level of contraindications increase, people need to apply more awareness and caution. Unfortunately, some teachers go in the other direction allowing people to feed into their ego and ride the desire to ‘achieve’ in practice into injury.
Please feel welcome to bring this topic up in the course – look forward to meeting you and sharing tons of information.
Namaste,
Kreg
I believe this, and all the claims of benefits never made sense to me. I tried hot yoga once and felt almost a little smothered by breathing hot, damp air, and I quit when I started feeling like I wanted to faint. That was enough for me!
While I have been to many hot yoga classes and enjoyed them, this reminded me of a class I took with the owner of the studio. He liked to turn the heat up extra high and, like a drill sargent, demanded that people push harder and deeper than they should have in poses. One time, I backed out of a pose to take a drink from my water bottle and take child’s pose for a few breaths, and he yelled at me in front of the whole class: “What are you doing? Don’t give into weakness! Now is not the time to hydrate!!! Now is the time for your breath, for your body,” he boomed. I was so upset and startled by this, I haven’t done hot yoga since then.
thanks Rachel … given that the true aim of yoga is find ‘union’ and ‘balance’ within your unique self, that approach to teaching you experienced appeared to contradict that intention … practice to your inherent vibrations and allow yourself to listen to what your body calls for … any instructor that tells you to ignore the messages coming from your body is not guiding you in the right direction
I do go to a hot yoga class and they tend to advise us not to leave the room mid class so we don’t shock our bodies.. but this is almost as much pushing as he requires. My general rule when doing yoga is listen to my body. There are times that hot yoga just feels right – it not toxins it sure enough squeezes tension and stress out of me… Then again I hear there are people who want to turn yoga into a competitive sport so what is a little heat on top of that.
Hi Denistsa,
There is no way that a person’s body would endure ‘shock’ by going from a heated room to a moderate temperature room. In fact, in Norway, they go from saunas right into freezing water (I would not do this personally). Overall, those claims of shock are ridiculous. Yet, more instructors, making unscientific claims for the sake of justifying their modality of practice. If a person is feeling nausea etc due to the heated room, that is SHOCK. The person should be removed from that environment as their body is unable to achieve steady state in that heat and need to shift to an environment (ie cooler) in which the body can return to a functional steady state or homeostasis. I can bet that those instructors telling you stay in a heated room while feeling nausea do not even know what ‘steady state’ is.
Now that I think about it you are right, since I myself have done the ice cold water. I need to pay more attention.Truth is some times it does require pushing past my better judgement to finish class, and we do still experience the “shock” once class is done and we go out of the room. Thanks for reminding me of my own rule – I will be more careful of how much I push from now on;)
Kreg:
Thanks for the insight. I live and teach in south Florida, a place where they love their hot yoga, to a point that it becomes an addiction. The college kids love and a lot of “Type A/Soccer Moms”, I have taken my share of classes and it really comes down to the teacher, so many I came across that are so mis informed, as well as not understanding the consequences. My beef? If a student can learn to turn on their own internal heat, then hot yoga wouldn’t be needed. However the heat, if it’s moderately at a balanced temperature (80-85), can be very beneficial for a “Kapha based” person. My wife’s dosha is Kapha and so the heat helps her, as well as the right teacher that has the right energy. That’s my two cents brother. Thank you again, I’m going to share this information.
Ernesto F. Bustamante
If its so dangerous, then why do I feel so fantastic after I do it? I’m onemof those apparently rare yoga teachers who doesn’t have a vendetta against hot yoga….I love it! 😉
Hi Kim,
No vendetta here. Merely offering factual information. Just as cross fit is not appropriate for everyone and can have contraindications, so too can any yoga class including Hot Yoga. It is important as teachers for us to remain objective from our passion of personal practice and insure that our teaching serves the unique needs of every student (including being able to determine if someone should not be doing a modality of exercise that is not appropriate). It is our responsibility as teachers to know all the fundamentals (physiology/anatomy/kinesiology) of exercise before attempting to manipulate peoples’ bodies. Thanks for your feedback. Kreg