Why We Breathe
From balancing carbon dioxide and blood pH to supporting circulation, respiration is a central driver of physiology.
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How three core signals reveal the state of your parasympathetic nervous system.
We live in an age of measurement.
Our watches count steps, our rings score sleep, our phones track stress. Yet despite all this data, few people actually feel more connected to their bodies. The problem isn’t a lack of information; it’s a lack of the right information at the right time — signals that reflect how the nervous system is actually performing, not just how much we move or how long we sleep.
Ohm was designed to surface only the essentials: three interrelated metrics that together capture the quality of your physiological state during resonance breathing.
We call them The Ohm Triad.
Together, they form a real-time map of how your body organizes itself into calm.
Heart rate is the simplest window into autonomic balance. A slower resting rate usually indicates stronger parasympathetic influence; a faster one suggests sympathetic activation or metabolic demand.
During a resonance session, we look less at the absolute number and more at its behavior: does HR gradually settle as you breathe, and does it rise and fall smoothly with each cycle? This rhythmic variation is a signature of a healthy baroreflex and balanced autonomic control.
Because each person’s baseline is unique, trends matter more than targets. Your own downward drift over weeks of practice is far more meaningful than comparing your HR to anyone else’s.
When you breathe slowly, your heart rate accelerates on the inhale and decelerates on the exhale. The difference between those peaks and troughs — the amplitude — reflects how dynamically your vagus nerve is regulating the heart.
Amplitude is what you can literally see on the tachogram as the wave height of each oscillation.
Larger, smoother waves mean stronger vagal tone, better cardiovascular flexibility, and a more responsive baroreflex (Lehrer et al., 2000).
But amplitude alone can be misleading. A high amplitude during physical recovery may coexist with elevated HR; a small amplitude in a drowsy state may still reflect healthy regulation.
That’s why Ohm normalizes amplitude by your average HR to express it as a percentage of modulation per beat — a fairer comparison across time and individuals. This “amplitude efficiency” view tracks adaptability, not just intensity.
Resonance is where physics intersects with physiology.
It describes how tightly the rhythms of breathing, heart rate, and blood-pressure waves align — how efficiently the system moves as one.
When these oscillations fall in phase (roughly 0.1 Hz, or about six breaths per minute), small inputs yield large, smooth changes in blood flow and heart rhythm.
On a graph, this looks like a clean, repeating sine wave; in the body, it feels like steadiness and ease.
The Resonance Score quantifies this alignment by measuring how much of your HRV signal’s power sits inside your personal 0.06–0.12 Hz window, weighted for timing stability.
High resonance means your breath isn’t fighting the heart — it’s smoothly pacing it in a calming, rhythmic pattern.
Many wearables distill HRV into a single number, but physiology isn’t one-dimensional.
Metrics like SDNN, RMSSD, or LF Power each capture useful fragments — but not the whole picture.
Each of these is a good lens — but only in isolation. The Triad combines three complementary dimensions:
Together they reveal whether the nervous system is synchronized, stable, and adaptive — not just “variable.”
It’s the difference between knowing your car’s speed and understanding its performance: engine RPM, torque, and fuel efficiency together tell the real story.
Most consumer devices take snapshots — brief HRV samples during sleep or static intervals of rest. Calm isn’t static; it unfolds in real time.
Ohm’s sensors capture continuously throughout each breathing session, at high sampling rates comparable to research-grade equipment.
You can literally watch resonance build, amplitude stabilize, and HR drift lower — a live view of your nervous system learning.
Continuous data also reveals micro-patterns that spot checks miss:
how quickly your system re-synchronizes after a distraction, or how amplitude grows over the course of a 10-minute session.
More numbers aren’t the goal. The aim is meaningful feedback that helps you adjust without overanalyzing.
The Triad acts like a small compass:
Together, they give you direction — which way your physiology is trending, and how quickly it finds its way back to balance.
In human physiology, direction matters more than position.
Everyone’s “normal” looks different, but positive change follows the same pattern:
Tracking these shifts over weeks or months is more meaningful than chasing a perfect number.
The goal of Ohm’s Triad is to give you a window into your nervous system’s performance — turning subtle rhythms into signals you can see and feel.
In a world overloaded with metrics, these three stand out for their simplicity and physiological truth. They show not just what is happening, but how well the body is coordinating its own balance.
Ohm makes that process visible, measurable, and—over time—trainable.
Lehrer, P.M., Vaschillo, E., & Vaschillo, B. (2000). Resonant frequency biofeedback training to increase cardiac variability. Applied Psychophysiology and Biofeedback.
Vaschillo, E., Vaschillo, B., & Lehrer, P.M. (2011). Characteristics of resonance in heart rate variability stimulated by biofeedback. Applied Psychophysiology and Biofeedback.
Lehrer, P.M., & Gevirtz, R. (2014). Heart rate variability biofeedback: How and why does it work? Frontiers in Psychology.
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