Have you ever cut weight in a steam room and then gone and checked on the scale and thought “how have I not lost more?” 


It’s a common occurrence for fighters and here is why I NEVER let my fighters cut weight in a steam room. 


To understand why you need to understand how our body effectively sweats, key word here is effectively. 


Sweating occurs when our core body temperature goes above 37C and that occurs whenever we are exposed to heat. That heat can be internal (produced by our muscles when we exercise) or external (provided by a sauna). Our body has to operate at a specific temperature otherwise everything breaks down (literally). So in order to manage it, when we detect a rise in core body temperature, we begin to sweat. 


To physically sweat, our body has to move fluid from what is called the extra cellular space. For simplicity sake, think of this space as the water in your blood, also called your blood plasma. This water then moves into a sweat gland where it is then pushed onto the skin. 


Once on the skin, the sweat will evaporate into the air through what is called an endothermic reaction, don’t sweat the big word, all you need to know is that for that type of reaction to occur it requires heat. So, your body takes the heat from the body and then turns the sweat into gas. If you multiply that over millions of sweat glands we cool very rapidly. Cool hey?


Well, here’s the detail you need to know that explains why I do not like steam rooms at all. 


For that sweat to occur, their needs to a humidity gradient, in other words, the air needs to be dry. That’s because the sweat needs to be able to evaporate into the air and fill the air with moisture. 


If there is no gradient, say the air is very wet like it is a steam room, then this evaporation does not occur and the sweat stays on the skin. This is problematic for two reasons; without evaporation the body won’t cool, and it will continue to overheat, and this overheating then leads to a slowing of sweat rate. 


So not only do you get hotter faster, you also lose less sweat for the same amount of time. 


That is why I do not like my fighters use a steam room. They add way too much heat stress and a much less effective than a traditional sauna. 


I hope this makes your next weight cut a little bit easier.


Yours in performance,


Jordi Sullivan