Wim Hof And The Real-Life Demon Slayer Breathing Techniques
From charging up ki in "Dragon Ball Z" to harnessing chakra to produce devastating ninjutsu attacks in "Naruto," most shonen anime usually grant their cast a specific way to store and use supernatural abilities. "Demon Slayer" is no different, although instead of powering up for multiple episodes or displaying a dazzling array of hand signals like Goku or Naruto, the series' Demon Hunters get their abilities from breathing.
The Demon Slayer Corps train their hunters in what's called breathing styles, and we're introduced to this through Tanjiro Kamado's training in Chapter 4 of the manga. Basically, the Slayer Corps use a form of concentrated breathing to increase the amount of oxygen in the blood and grow lung capacity. This, in turn, grants them a level of super physical and mental abilities that puts them on par with Demons. We see the use of this total concentration breathing in numerous powers throughout "Demon Slayer," from awesome sword attacks to significantly increasing spatial awareness. There seems to be no shortage of how breathing benefits these hunters.
What's intriguing about the use of total concentration breathing in "Demon Slayer" is that in real life, it's not a far-fetched concept. Deep breathing exercises have been documented for reducing stress and increasing performance for soldiers and athletes (via Healthline). In fact, one extreme athlete by the name of Wim Hof has based his record-breaking feats on his own type of breathing technique.
The Iceman withstands extreme cold through his breathing exercises
Wim Hof is a Dutch athlete who has earned the nickname "Iceman" thanks to some of his amazing accomplishments. For example, he currently holds the title in the Guinness Book Of World Records for the fastest half marathon run barefoot, with a time of a bit over two hours. And, via the South China Morning Post, Hof has set a record for submerging himself in ice for nearly two hours and has climbed Mount Everest in only his shorts.
Hof has long attributed his amazing feats to his own type of deep-breathing exercise combined with exposing himself to extreme cold, which he's dubbed the Wim Hof Method. While the claim about exposure to extreme cold has not yet been scientifically supported, according to an article from the Smithsonian Magazine, there are clear benefits to Hof's method of deep breathing. A study found that Hof's deep breathing basically allows his mind to force a stress response in the body that resists the effects of cold. In fact, the study also said that Hof can enter a euphoric state through his breathing method while placed in such an extreme environment.
So while regular people may not be able to really do Water Wheel like Tanjiro, Hof clearly shows that there are some real potential benefits to deep-breathing techniques.