I read a few different articles on this and the method seems to basically be the same. It reminds me of a meditation practice that someone told me about. This is something we all should practice. This is not just for during combat. This is a useful technique to use during stress full situations you may encounter in your life. Many tend to do fast breathing when encountering a stressful situation. You need to slow it down so that you can think and properly react. If you are one who tends to hold their breath instead of hyperventilating then this exercise will help you in releasing your pent-up breath. Tactical Breathing Can Stop Stress on the Spot | On Resilience I have attached a pdf you may want to print off. Practice breathing now so you can focus on what needs your attention when emergencies arise.