High ventilation
This site does not time holotropic or Grof breathwork, rebirthing, Wim Hof breathing, cyclic hyperventilation with retention, or prolonged conscious connected breathing at a high rate.
These practices can bring tingling, cramping, dizziness, and fainting. The Start is two minutes. It does not set a rate or a breath hold.
An overview is Fincham and colleagues, Neuroscience & Biobehavioral Reviews, 2023.
Safety is where the stop-if guidance lives.