Your heart doesn’t beat like a metronome, and that variability between beats reveals everything about your body’s ability to handle modern stress. I get tons of questions about HRV, and here’s what you need to understand: HRV measures the balance between your sympathetic nervous system (fight-or-flight) and parasympathetic nervous system (rest-digest), and research published in Frontiers in Neuroscience shows it’s a powerful non-invasive biomarker linked to mental and physical health.
