Breathing practices that emphasize vigorous inhales over passive exhales, such as Tummo or Wim Hof breathing, lead to increases in heart rate.

“The opposite is also true. If you inhale deeply or vigorously and then exhale less long or less vigorously, you will increase your level of alertness through these purely mechanical aspects of your interoception.”

“And then practices such as Tummo breathing or Wim Hof breathing or cyclic hyperventilation, [HYPERVENTILATES] deep inhales and exhales, the inhales are more vigorous compared to the more passive exhales-- are going to lead to increases in heart rate.”

“if you inhale vigorously and long your heart rate goes up if you exhale vigorously and long heart rate goes down through a process called respiratory sinus arhythmia volume of the heart changes when you breathe in versus breathe out speed at which blood moves through the heart changes as the blood gets bigger or smaller according to inhales exhales and basically the net effect is inhale heart speeds up a little bit exhale heart slows down a little bit so so if you do Wim Hof AKA Tumo breathing and you inhale vigorously and let it fall out of your mouth and then you're going to increase heart rate increase autonomic activation Etc”