Whole-body cryotherapy is just what it sounds like: the whole body is exposed to ultra-cold temperatures. Cryos users step into the chamber and the frigid temperatures instantly send the body into a natural fight or flight response. As blood vessels constrict, blood is redirected away from the extremities and toward the core in order to protect the organs. The body then becomes charged with oxygen and anti-inflammatory proteins, and excess white blood cells are flushed out, boosting the metabolic rate. Exposure to cold like this promotes increased blood flow which brings fresh, oxygenated blood full of white blood cells to areas of the body that need it. Whole body cryotherapy amplifies these positive effects and adds many more incredible benefits by activating the vagus nerve and causing vasoconstriction and vasodilation. The vagus nerve is responsible for the regulation of internal organ functions. The vagus nerve is activated by cold on the back of the neck and touches every major organ in the body. After exiting the cryo chamber, blood vessels dilate and rush oxygen-rich blood and endorphins back through the body. And then, in an effort to warm itself back to equilibrium, the body undergoes a metabolic reaction that can burn on average 800 calories.