The HRV Book — Don Moxley
A Book by Don Moxley

Your ring reads the weather inside you. This book teaches you to change it.

The HRV Book turns your Oura ring or WHOOP band from a daily report card into a working tool, written by a sport scientist who spent four decades coaching Olympic and world class athletes.

Thermometer — a reading Thermostat — a response
The Core Idea

A thermometer tells you the temperature. A thermostat changes it.

Your ring or band works like a thermometer. Each morning it reads your heart rate variability, the beat to beat variation in the time between heartbeats, and hands you a number. That number describes the balance between two systems inside you: fight or flight, which prepares your body to meet a threat, and rest and digest, which restores it afterward. The HRV Book teaches you to act on that number instead of only receiving it, the way a thermostat holds a room at a chosen temperature instead of just reporting how cold it is.

What the ring measuresFight or Flight

The system that prepares your body to meet a threat. It raises heart rate, tightens muscles, and sharpens attention. Training, stress at work, and poor sleep all draw on it in the same way.

What the book buildsRest and Digest

The system that restores you afterward. It slows heart rate, supports digestion, and rebuilds tissue. The HRV Book shows you the specific practices, sleep, breath, and the relationships in your life, that strengthen it on command.

Who It’s Written For

Written for three readers in the same house.

The nervous system that shows up in a wrestler’s warmup is the same one that shows up in a parent’s inbox and a grandparent’s knees. The HRV Book was built to speak to all three without asking any of them to skim past the others.

01

The Competitive Athlete

Training load, recovery, and the difference between adapting to stress and maladapting to it, read straight off the device already on your wrist.

02

The Working Parent

The same nervous system that responds to a hard interval session responds to a hard week at the office and a harder one at home.

03

The Grandparent

What HRV reveals about the changes that come with age, and what remains within your control no matter which decade you’re in.

“Help individuals understand the changes necessary to alleviate suffering and contribute to the betterment of well people.”

Don Moxley
Inside the Book

Five parts. Twenty-two chapters. One working tool.

The HRV Book moves from the physiology under your data to the daily practices that change it, ending with the question every number is ultimately in service of: what you’re building your recovery for.

Part One

The Physiology

How fight or flight and rest and digest work, and why their balance is what your device is actually reading.

Part Two

The Science

What HRV reveals about aging and nervous system balance, and where the research is settled, emerging, or still contested.

Part Three

Your Device

How to read Oura, WHOOP, Polar, and NOWATCH specifically, with the validation research behind each one.

Part Four

The Practice

Sleep, breathwork, vagus nerve stimulation, training load, cold and heat, nutrition, and the relationships that regulate you.

Part Five

The Long Game

Meaning, purpose, and what a lifetime of well regulated recovery is ultimately building toward.

Get the Book

Stop reading the weather. Start setting it.

The HRV Book is available now. Join the list to hear the moment it launches, or reach out directly to request an early copy.