If we hooked you up to an EKG right now, we’d watch your resting heart rate plummet and your HRV climb dramatically. No supplement, no $400 device, just your own physiology doing what it was built to do. As an exercise physiologist and biomedical neuroscientist, I work with some of the most demanding founders, CEOs, and athletes in the world, and this is the fastest, most accessible way to flip into parasympathetic mode. You don’t need more gadgets or gimmicks, you need interoception and the protocol itself. It’s a modified 4-7-8 breath. Four second inhale, seven second hold, eight second exhale. A few things make it work. Breathe horizontally into your belly and diaphragm rather than vertically into your chest, because that’s where you recruit the vagus nerve and trigger the rest, digest, and heal response. Inhale through your nose only, and lean into the air hunger, because that urge to breathe means CO2 is building, and CO2 is slightly acidic, slowing your heart through a car...