How to Track and Make Use of Your Health Metrics
wearables, getting the most out of your 21st century technology, etc
By the end of this post you will know
The four signals that change what you do today: resting heart rate, heart rate variability, sleep efficiency, and a simple morning temperature trend.
What your phone already tracks across mobility, heart, sleep, hearing, medications, mood, cycle, respiratory markers, and energy
How to pick metrics by goal, mute the rest, and run a weekly loop that leads to one clear decision each day.
Technology should answer to you. Not the other way around. A tool earns space when it makes choices simpler and your day quieter. If a device wants your attention and gives you no leverage, it is clutter with a battery. One way you can tailor your devices is with health metrics that matter to you. Your phone, watch, ring, or band can collect an ocean of personalized signals without a single ping. Your job is curation.
A few months ago I kept crashing after my morning protein. Lift at seven, shower, breakfast, laptop, then a wall by nine thirty... AM!
Sleep was solid. Breakfast was clean. The dip kept showing up.
So I ran a real audit. I wore a continuous glucose monitor (CGM), for two weeks to test breakfast and timing. CGM is a short course, not a lifestyle, but it is useful for linking choices to outcomes in real time. I saw a pattern that was obvious by day four. Fasted training before the gym raised cortisol and primed me for a sharper swing. Caffeine after food was calmer. A quick whey shake alone hit fast, which tracks with whey’s insulinotropic effect. Adding fiber and fat slowed the curve. A ten-minute walk after the meal flattened the peak and kept energy even through late morning.
The lesson is simple. Data earns its place when it changes what you do today. If a number does not alter training, meals, or wind down, it is decoration.
The Top Four
Before we talk platforms and features, choose the signals that actually change what you do today. Four belong on your first screen. Everything else can support from the archive.
Resting heart rate
What it is: lowest sustained heart rate at rest, usually captured overnight.
Why it matters: mirrors recovery and cumulative load. Illness, alcohol, late meals, and stress push it up. Training age pulls it down over time.
How to read it: compare today to your baseline. A rise of a few beats for two mornings is a caution sign. A small drop after an easy day often means you can push.
Moves to try: if elevated, bring dinner earlier, reduce intensity, add a ten-minute walk after meals, and protect sleep. If steady or lower, schedule your key work block or session.
Heart rate variability
What it is: tiny beat-to-beat changes in rhythm. Higher at rest usually means more flexibility.
Why it matters: tracks how you adapt to stress, training, and travel. Pairs well with resting heart rate because one rises as the other falls when recovery is solid.
How to read it: use a rolling average. A dip below your seven to fourteen day mean for several days argues for a hold or recovery. A rebound supports a push.
Moves to try: if HRV is down, shorten intensity, get morning light, and do five minutes of slow breathing near six breaths per minute. If HRV is up, lean into creative work or quality training.
Sleep efficiency
What it is: the percentage of time in bed that becomes real sleep.
Why it matters: reveals whether timing and environment support recovery.
How to read it: watch the weekly trend. Low runs often track with late eating, alcohol, or long evening screens.
Moves to try: protect a two to three hour gap between dinner and lights out, dim the home an hour before bed, park the phone outside the room, and keep wake time consistent for a week.
Morning temperature trend
What it is: a simple waking trend from a ring, a skin sensor, or a basal thermometer.
Why it matters: responds to illness, inflammation, cycle shifts, late strain, and travel. It often moves before you feel off.
How to read it: establish a seven to ten day baseline. A bump above usual, paired with higher resting heart rate and lower HRV, calls for a lighter day. A stable or slightly lower trend with solid HRV supports a push.
Moves to try: if temp drifts up, reduce intensity, hydrate, bring meals earlier, and get morning light. For women, expect luteal-phase rises and read other signals in that context.
Why these four work together
They cover recovery, stress flexibility, sleep quality, and hidden load. They respond to choices you control and lead to clear actions. If two or more drift the wrong way, simplify the day and protect recovery. If all four hold or improve, plan a push.
What your phone and Health apps already capture
Think in domains. The names vary across Apple Health, Google Fit, Samsung Health, Garmin Connect, and Fitbit, but the categories overlap.
Mobility and gait. Steps, distance, pace, walking speed, step length, asymmetry, and a Walking Steadiness classification on iPhone that draws on motion sensors. You will find it under Mobility in Apple Health.
Heart and cardio fitness. All-day heart rate, resting heart rate, HRV, training zones, VO₂ max estimates, and ECG on supported watches. Trends live in the Health app if you use Apple Watch.
Sleep. Time asleep, sleep stages, and efficiency derived from motion and heart data, with weekly trends inside Health.
Hearing and environment. The Noise app on Apple Watch samples environmental sound, shows daily and weekly decibel exposure, and can alert you when levels get risky. Headphone audio levels sit in the same Health section.
Medications. You can log meds, vitamins, and supplements, schedule reminders, enable follow-ups, and in the U.S. review Moderate, Serious, or Critical drug interactions in Health.
Mental wellbeing. State-of-mind logging and mood insights live under Mental Wellbeing in Health.
Cycle tracking. Period logging, fertile window predictions, and on supported Apple Watch models, wrist temperature improves retrospective ovulation estimates.
Respiratory and oxygen. Respiratory rate during sleep and SpO₂ on supported devices appear in Health. Availability can change by model and region.
Energy and hydration. Active and resting energy are modeled to show total daily expenditure. Water intake can be logged manually, via Shortcuts, or with a smart bottle app.
Mobility and gait: steps, distance, pace, walking speed, step length, asymmetry, Walking Steadiness on iPhone.
Heart and cardio fitness: all-day heart rate, resting heart rate, HRV, zones, VO₂ max or cardio fitness, ECG on supported watches.
Use this as the base layer. It already covers most people’s needs.
Where rings and bands are pushing the frontier
Rings and bands synthesize recovery and longevity signals that otherwise live across many screens.
Oura Ring. Readiness blends HRV, resting heart rate, temperature trends, and recent strain to guide effort. Cardiovascular Age compares your cardiovascular profile to your chronological age once you have enough nights of data. New women’s health features layer temperature, HRV, resting heart rate, and symptoms into pregnancy and perimenopause views with shareable reports for clinicians.
WHOOP. Recovery and Strain act as daily anchors so you know when to push or hold. A Health Monitor tile brings HR, HRV, respiratory rate, SpO₂, and skin temperature into one view, and the platform flags unusual shifts that may merit rest.
Garmin. Body Battery estimates your usable energy from HRV, stress, sleep, and activity. HRV Status and Training Readiness use overnight HRV and recent load to shape the day. Garmin is also expanding sleep-first devices that prioritize recovery comfort.
Fitbit. Daily Readiness uses HRV, sleep, and recent activity to rate preparedness. Stress Management Scores combine HRV, exertion, and sleep to show physiological stress and coach down-shifts.
Scales and smart home health. Withings Body Comp estimates Vascular Age and supports pulse-wave velocity where available. This brings arterial stiffness, a longevity-relevant signal, into a morning step-on.
These systems are context that can sharpen decisions about training, food timing, recovery, and clinical follow-up.
Choose metrics by goal, not by default
Turn off what you will not use. Keep what changes behavior. Use this map to decide what should be a notification for you.
Sleep and recovery steady. Keep resting heart rate, HRV, sleep efficiency, and a simple morning temperature trend. Actions to test this week: bring dinner earlier, darken the bedroom, morning light within an hour of waking.
Metabolic steadiness. Keep post-meal notes, step count as a walk cue, and consider a two to four week CGM block to learn your curve. Actions: protein and fiber first at meals, ten minutes of walking after you eat, earlier caffeine.
Aerobic fitness. Keep VO₂ max or cardio fitness, weekly training load, and resting heart rate. Actions: two easy zone sessions, one tempo, one hill set, then a hold when recovery dips.
Strength and body composition. Keep training volume, weekly frequency, HRV for readiness, and a morning body-weight trend if you are actively recomping. Actions: progressive overload, protein target by body weight, a real rest day when HRV and mood both sag.
Focus and stress resilience. Keep HRV trend, sleep regularity, and sound exposure. Actions: one six-breaths-per-minute session, mid-day outdoor walk, safer headphone levels in loud spaces.
Cycle-informed training. Keep cycle phase, sleep, resting heart rate, and temperature trend. Actions: for many, heavier lifts and PR attempts in the late follicular window, more recovery emphasis late luteal if sleep and mood dip.
Longevity orientation. Keep resting heart rate, HRV trend, VO₂ max or fitness age, walking speed, and weekly strength sessions. Add a monthly grip-strength check with a simple dynamometer.
Set rules for your stack
Wearables are an edge when you curate them. Make your attention a scarce resource. Choose the few signals that change your behavior and let the rest sit quietly in the background. Read trends by the week and make one decision that shapes the next twenty-four hours.
Weekly data edit: Pattern I see → Hypothesis → One change for 7 days → Result → Keep or retire.
Finish with a simple loop. Review once each week. Write one small test for the next seven days. Each morning ask two questions. Did I recover well enough to push. If not, what will I change. Then act. That is how modern sensors become a quiet advantage instead of more noise.
Until Next Time,
Natalie, Editor In Chief of thedweller.co
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