Recovery & Readiness for iPhone

How is your
body today?

Body Battery reads your HRV, resting heart rate, sleep and workouts to compute a clear, personal picture of your readiness — so you can decide whether to push, maintain, or recover.

Powered by Apple HealthPersonalized to youPrivacy-first

Powered by Apple Health

Reads HRV, RHR, sleep stages and workouts you already track.

Personalized to your baseline

Compares today to your last 30 days, not to a generic average.

Watch & Widgets

Glance at readiness from your wrist or home screen.

Privacy-first

Health data stays inside the Apple Health permissions you grant.

01How it works

Real signals.
Clear answers.

Body Battery quietly reads four signals from Apple Health and turns them into one coherent system of daily metrics. No new sensors. No new wearables. Just a sharper read on what you already track.

Inputs · Apple Health

Heart-rate variability
HRV
Resting heart rate
RHR
Respiration rate
RESP
Blood oxygen & temp
SpO₂
Sleep stages & duration
SLEEP
Workouts & VO₂
EXR

Outputs · Body Battery

Readinessprimary
Recoverytrend
Batterylive
Stresstrend
Sleep scorenightly
Exertiondaily
02Core metrics

One system.
Six clear numbers.

Readiness sits at the centre. The other metrics explain it — what's recovered, what's drained, what's accumulating — so you understand the score, not just glance at it.

Readiness

Primary · 0–100
85High
85
25507590

A single, personal number from 0–100 that answers one question: how much do you have today? Calibrated against your own last 30 days, not a population average.

Recovery

HRV-driven
83%

How well your nervous system bounced back overnight. Based on HRV and resting heart rate against your trend.

Battery

Live
92%

Your real-time energy reserve. Drains with stress and exertion, recharges with rest and sleep.

Stress

Low today
19

Sustained sympathetic load inferred from heart-rate dynamics during non-workout time. Lower is better.

Sleep

Nightly
58%

Sleep quality score combining duration, deep and REM stages, weighted against your need.

Exertion

Hard target
0.0TARGET 5.4 — 8.8
0510

Today's effort against your prescribed window. Stay in the green to progress without overreaching.

03Why it's different

Push, maintain,
or recover?

Most apps tell you what happened. Body Battery tells you what to do with today. Three honest options, recommended from the data — never a generic plan.

75–90 · High zone
Push

HRV above baseline, sleep was solid, recent load in range. A hard session — intervals, threshold, a PR attempt — is well within reach.

50–75 · Green zone
Maintain

You're recovered but not peaking. Hold the rhythm: zone-2 work, technical drills, and let the trend keep building.

Below 50 · Caution
Recover

HRV is suppressed or load has stacked. Choose mobility, an easy spin, or a true rest day — the gain comes from absorbing.

01

Personal, not population

A 60 for you isn't a 60 for someone else. Your scores are calibrated against your own rolling 30-day window, so good days look good and bad days look bad — for you.

02

Trends over noise

One night doesn't change a season. Body Battery weights longer-term trends so a single late dinner or a missed run doesn't tank your guidance.

03

Decision-shaped

Every screen is built around one question — push, maintain, or recover? — instead of an undifferentiated dashboard of charts.

04

Quiet by design

No streak shaming. No alarmist red. The app stays out of the way until something actually warrants your attention.

04Trends & workouts

Patterns you'd
otherwise miss.

Body Battery looks across weeks, not just days. The acute-to-chronic load ratio, training effect rings and zone-coloured heart-rate timelines turn raw activity into actionable shape.

Training Load Ratio

30 Days60 Days
ACWR
0.45
Status: Low
LowOptimalHighRisk
SHORT LOAD (7D)
27
LONG LOAD (28D)
60

Suggestion: increase weekly load by ~5–10%.

LOW OPTIMAL HIGH RISK SHORT LONG

Workout · Thursday 23 Apr

Detail
DURATION
2h 47m
CALORIES
1834kcal
AVG HR
128bpm
Effort7,85
Very hard
Heart Rate
MAX
170bpm
AVERAGE
128bpm
16:4717:4318:3919:35
Z1Z2Z3Z4Z5
Training Effect
3.9
AEROBIC
Improving
3.6
ANAEROBIC
Maintaining
05Transparency

Scores you can
actually read.

Every number can be opened up. Tap a metric and you see the inputs behind it, weighted by what changed today versus your baseline. No black box, no mystery wellness math.

Today's readiness

82 — what's behind it.

A breakdown of the four signals shaping your score, ranked by impact. Green bars push readiness up; amber bars pull it down. The score updates as new data syncs from Apple Health.

HRV vs. baseline
+12
Sleep duration
+8
Sleep quality
+5
Resting HR
4
7-day load
3
06Apple ecosystem

At home on iPhone,
iPad, and Watch.

Body Battery is built only for Apple. That's the point — every surface is designed to fit the device it's on, from a glanceable widget to a full Watch face complication.

Apple Health

A read-only relationship

Connect once. Body Battery requests only the categories it needs and re-requests permission whenever scope changes.

Heart variability
Resting heart rate
Sleep analysis
Workouts
Active & basal energy
Apple Watch

Readiness, on the wrist

A complication for your favourite face plus a quick look at recovery, battery and stress without unlocking your phone.

Home Screen widgets

Three sizes, one glance

Small for the score, medium for the day's verdict, large for trends. Lock-screen complications too.

07 — Privacy

Your health data stays where it belongs.

Body Battery reads only what Apple Health permissions you grant. We never sell health data, never share it with advertisers, and don't use it to profile you. You can revoke access in one tap and your scores stop computing the moment you do.

No adsNo data saleNo third-party analytics on health dataRevoke access anytimeApple Health permissions
08FAQ

Answers, not
asterisks.

Short, direct answers to the questions we get most. Anything else, write in — the team reads everything.

A single 0–100 number that estimates how much capacity you have today. It blends recovery (HRV and RHR), sleep, and the trailing load from your workouts, then compares all of that to your own 30-day baseline.

Available for iPhone

Train smarter.
Recover better.

Connect once to Apple Health and get a clear, daily read on what your body has — and what to do with it.