A week built for you.
Shaped by the training you have already done and by how recovered you are this morning, rather than by a template everybody gets.
The beta is open for iPhone
A week
that fits.
Metrion reads the years of training already in your Apple Health, writes your week from them, and changes that week the day your life changes.
See what it doesFree while the beta runs. Made for iPhone, with an Apple Watch app.
YOUR TRAINING LANDSCAPE
28 DAYS, IN PERSPECTIVE
28 DAYS, IN PERSPECTIVE
Today
TRAINING LOAD
48
Steady run · planned
ILLUSTRATIVE TRAINING HISTORY
READINESS
86
FRESH
Room to move today.
SLEEP
8h12m
Last night, from your watch.
RECOVERY
62ms HRV
Measured while you slept.
TRAINING
28days
Of training behind today.
3W AGO
TODAY
Each slice is one day,
and its height is how hard it was.
SLEEP · RECOVERY · TRAINING
ILLUSTRATIVE HEALTH DATA
↓︎
What today’s advice is built from.
01 / Why it asks what it asks
You are more
than your
numbers.
Your training only makes sense next to the week you had around it.
Metrion reads both, so the session it asks of you tomorrow is one that fits the week you are actually having.
02 / What you get every morning
Today’s session,
and the reason
it changed.
Your week comes from the training you have actually done, and it changes when your life does. Ask why at any point and the answer comes back in your own numbers.
It moves when you do.
Tell it you are ill, away or short of time, and the week changes, with what moved and why written on the day it changed.
A coach you can ask.
It has read every workout you have recorded, going back years. Ask it anything about them and it answers in your own numbers.
A CLEARER VIEW
OF YOU.
OF YOU.
TODAY · THU 17 SEP
A fuller day,
with a higher cost.
An extra 9 minutes of easy work this day. Nothing to change.
SIGNAL
Average heart rate was 45 bpm above your recent workout pattern.
Check your sleep ↗
DONE
Run 54 min
Load 110 · 159 bpm average
HELD
Long walk
87 min · Zone 1
THIS WEEK
The hard work this week went past what the plan asked for.
LAST 7 DAYS · FORM −29 · BUILDING 7D
594 load · 8 workouts
Easy walk · 18:24 6:41
You are on
136 bpm · zone 2
1
2
3
4
5
14 of 30 min in zone 2
4 × 4 minutes 6:58
Hard
1:12
then 3:00 easy · rep 2 of 4
1
2
3
4
5
161 bpm 9.4 of 16 hard min
03 / A living landscape
Every effort leaves a mark.
Four weeks of your own training drawn as one shape, so you can see where the hard work landed and where there is room for more.
Your training, in perspective
ILLUSTRATIVE DATA
28 days of training, drawn as one shape.
Today
Steady run · planned
TRAINING LOAD 48
3 WEEKS AGO
2W
1W
NOW
DRAG TO PICK A DAY
Easy
Moderate
Hard
Planned
Fitness
Fatigue
View the training data
| Day | Session | Load |
|---|---|---|
| Mon 17 | Easy run | 36 |
| Tue 18 | Steady ride | 53 |
| Wed 19 | Recovery walk | 18 |
| Thu 20 | Hill repeats | 86 |
| Fri 21 | Rest day | 0 |
| Sat 22 | Long run | 94 |
| Sun 23 | Easy walk | 22 |
| Mon 24 | Easy run | 39 |
| Tue 25 | Steady ride | 57 |
| Wed 26 | Rest day | 0 |
| Thu 27 | Tempo run | 77 |
| Fri 28 | Recovery walk | 21 |
| Sat 29 | Long ride | 91 |
| Sun 30 | Easy walk | 19 |
| Mon 31 | Easy run | 42 |
| Tue 01 | Steady ride | 62 |
| Wed 02 | Rest day | 0 |
| Thu 03 | Intervals | 88 |
| Fri 04 | Easy walk | 20 |
| Sat 05 | Long run | 96 |
| Sun 06 | Rest day | 0 |
| Mon 07 | Easy run | 38 |
| Tue 08 | Steady ride | 56 |
| Wed 09 | Recovery walk | 17 |
| Thu 10 | Tempo run | 74 |
| Fri 11 | Rest day | 0 |
| Sat 12 | Easy run | 33 |
| Today | Steady run · planned | 48 |
04 / What it actually does
Where your week comes from,
and why it changes.
Your phone can already tell you what you did. Metrion works out what you should do next, changes it when your week changes, and tells you why on the day it changed.
On the plan screen
The week moves
when your life does.
You told the coach you were ill. Saturday’s 91-minute long walk became rest, and this week’s plan fell from 4.4 hours to 2.9. The reason sits on the day it changed. Feel better tomorrow, and you put it straight back.
- Each change says what the day was before and what changed it.
- Today, your plan and your coach tell you the same thing, in the same words.
- When the week has to shrink, the hard days go first and the easy days stay as they were.
PLAN · MON 14 – SUN 20 SEP
This week
is on track.
1.5
/ 2.9 h
DONE OF THIS
WEEK’S PLAN
You set 7 hours a week.
MINUTES A DAY · SOLID IS DONE, OUTLINE IS PLANNED
You reported an illness, so Saturday is a rest day, not a 91-minute long walk.
SAT 19 · SELECTED CHANGED
Rest
Nothing planned
AN EXAMPLE WEEK · YOUR OWN PLAN SCREEN
Before the week is built
Built around the life
you actually have.
A race date, a fortnight away, a cold, a week with no room in it or the equipment in your hallway can each change what your week asks of you, and the plan tells you which one did it.
- Give it a race and a date, and it builds towards them, then tapers. If the date is too close to prepare for, it says so.
- Say you were ill, injured or away, and those days stop counting against you, so a fortnight off does not read as lost fitness.
- Train in another time zone and the week still adds up, because every session keeps the clock you trained on.
- Strength is built from the equipment you own. It never asks you for a bar you do not have.
Seven weeks. Build, then taper.
- M Easy 30
- T Rest
- W Quality 40
- T Easy 30
- F Rest
- S Long 95
- S Easy 25
The long session grows week by week and the last two weeks come down, so you arrive rested rather than tired.
Those days leave your usual ranges.
- M Rest
- T Rest
- W Easy 25
- T Rest
- F Easy 30
- S Easy 35
- S Rest
A fortnight away does not read as lost fitness, and the week you come back to starts where you left off, not where the plan had reached.
Hard work goes first. Easy work stays.
- M Easy 30
- T Rest
- W Easy 30
- T Rest
- F Rest
- S Rest
- S Easy 25
The quality session becomes an easy one and Saturday becomes rest. Nothing easy is taken away, because easy work is not what makes you worse.
Three sessions, not six.
- M Rest
- T Quality 35
- W Rest
- T Easy 25
- F Rest
- S Easy 40
- S Rest
You keep the one session that carries the goal. The rest of the week is written to fit what is left, rather than set to fail.
Five patterns, all of them yours.
- M Easy 30
- T Strength
- W Quality 40
- T Rest
- F Strength
- S Long 75
- S Easy 25
Squat, hinge, push, pull and a carry, built only from what you own. A pattern with no owned option is dropped, never swapped for something you cannot do.
In the coach thread
Ask about your record,
and get your own numbers back.
Years of workouts, nights and morning readings sit on your phone. Ask the coach anything about them. It reads them, compares the two stretches of time you named, and answers with the chart or the card that suits the question.
- Every number in an answer comes from your own records, and is checked against them before you see it. Anything it cannot check is not shown to you at all.
- When two apps disagree about you, it asks you which is right, and the question waits until you answer it.
- It remembers the conversation, so “which dates do you mean?” has an answer.
YOU Am I fitter than I was two years ago?
Your cardio fitness reads 51.8, against 47.6 two years ago, which is far more than the month-to-month wobble in your own readings.
CARDIO FITNESS
SEP 2024
47.6 ml/kg/min
SEP 2026
51.8 ml/kg/min
23 OF THE 24 MONTHS CARRY A READING · JULY 2025 HAS NONE
TWO YEARS APART
SEP 2024
47.6
SEP 2026
51.8
AN EXAMPLE ANSWER · IN THE APP THESE ARE YOUR NUMBERS
Under every number
It would rather say
it does not know.
Every figure comes from your own records, or from research it names. When the evidence does not stretch that far, it tells you, instead of turning it into a compliment.
- When a workout reading quotes research, the study is named under it, so you can look it up yourself.
- Your zones are the zones your watch uses, so the two never disagree about the same session.
- Your fitness age names the published table it was measured against, and says where you do not fit it.
You went hard 5 times in this walk, about 60 seconds each, with 7 minutes easy between them. For aerobic capacity that is short of the three to five minute efforts the benefit was tested at, so I cannot claim it here.
- Three to five minute efforts
- HELGERUD ET AL. · MED SCI SPORTS EXERC · 2007
THE READING NAMES THE RESEARCH IT QUOTES
On your wrist
Your wrist becomes
the instrument.
Start a walk or a run in the Metrion watch app and the session is on your wrist. The bubble you know from your phone says whether you are on the effort, above it or below it, with your heart rate in the middle of it. Underneath sits the number no other display gives you, which is how many of the minutes your plan asked for you have actually held. When you finish, the watch saves the workout to Apple Health, as any workout app does.
- Zone 2, 18 of 30 minutes, counting only the minutes that landed in the zone rather than the minutes you were out.
- Intervals and walk-run sessions count the block you are in down to zero, and name the one after it before it starts.
- A glance at your wrist is enough, with nothing to work out.
Easy walk · 18:24 6:41
You are on
136 bpm · zone 2
1
2
3
4
5
14 of 30 min in zone 2
4 × 4 minutes 6:58
Hard
1:12
then 3:00 easy · rep 2 of 4
1
2
3
4
5
161 bpm 9.4 of 16 hard min
THE WATCH APP COMES WITH THE IPHONE APP IN TODAY’S BETA.
Before you go out
One line
about the heat.
What it feels like outside, and how much slower to go for the same effort. Your heart-rate target stays where it is, because the heat has already raised it. When the heat is bad enough to matter, it tells you to take that one indoors.
- Temperature and humidity from Apple’s own weather service.
TODAY · FRI 18 SEP · INTENTION
Long walk
45 min · Zone 1 · keep it under 125 bpm
Feels like 43 degrees. Go about 15 percent slower for the same effort.
FEELS LIKE 43° HUMIDITY 58%
In trends
From a first walk
to a tenth year.
Metrion reads every year Apple Health holds for you, however far back that goes. Compare this month with the same month two years ago, or with your very first.
- If you are three weeks in, it will not hand you intervals, while two years of running gets them in week one.
2016 TEN YEARS OF CARDIO FITNESS 2026
Records reach back to 3 March 2016.
WHAT THE TRAINING IS FOR
For the days
you feel
like yourself.
THE POINT IS THE HOUR
YOU SPEND OUTSIDE.
YOU SPEND OUTSIDE.
Metrion asks for the session that fits today, so training stays something you keep doing rather than something you keep restarting.
05 / The coach
Every workout,
read properly.
When a workout ends, Metrion reads it against the week you are having, then tells you what it did for your goals in your own numbers.
01 / THE WORK YOU DID
Morning run
JUST FINISHED
42
min
DISTANCE
6.8 km
AVG. HEART RATE
136 bpm
THE SHAPE OF YOUR EFFORT
0 MIN
21 MIN
42 MIN
42 min easy
0 min hard
IN THE CONTEXT OF YOUR WEEK
An easy run, just as planned. Your harder session is already behind you this week.
Workout received.
Now reading it against your week.
Now reading it against your week.
02 / WHAT IT MEANS FOR YOU
Your personal coach
Writes to you after every workout.Easy all the way, just as planned.
-
You kept this one easy from start to finish, which is what the plan asked for.
-
Your pace stayed close to your usual easy run.
-
With your hard session already done, this run gave the week a little more balance.
YOUR GOAL / BUILD ENDURANCE
+42 min of easy work
You’re building endurance. Today added easy time on your feet, the kind of work your longer runs build on.
Easy run · 35 min
01 / THE WORK YOU DID
Morning run
JUST FINISHED
58
min
DISTANCE
9.2 km
AVG. HEART RATE
161 bpm
THE SHAPE OF YOUR EFFORT
0 MIN
29 MIN
58 MIN
25 min easy
33 min hard
IN THE CONTEXT OF YOUR WEEK
Planned as easy, it finished hard, and it is your third hard session this week.
Workout received.
Now reading it against your week.
Now reading it against your week.
02 / WHAT IT MEANS FOR YOU
Your personal coach
Writes to you after every workout.Harder than planned, so the next one is easy.
-
This was meant to be an easy day, but much of the run became hard work.
-
You’ve already pushed hard earlier this week. Today added more strain to that picture.
-
Your next hard session becomes easy work, so the week has room to absorb today.
YOUR GOAL / BUILD ENDURANCE
+25 min of easy work
Today still counts towards your endurance goal, and recovering from it is how that work turns into fitness.
Intervals
Easy run · 35 min
TWO EXAMPLES OF A WORKOUT READING
Interactive demo · Illustrative workouts and coach responses.
A coach that has read your record.
It knows your whole record.
Every workout, every night and every morning reading, going back years. Ask about any of it in plain words and you get a plain answer.
It answers in your own numbers.
It draws a chart when that is clearer than a sentence, with the numbers it came from underneath.
It tells you when it does not know.
If your record does not stretch far enough to answer you, it says so. You never get a confident number with nothing behind it.
It explains every change to your week.
It says what moved, what it was before and what changed it. Where the day is safe to keep, you can put it straight back.
It asks you things.
When two apps disagree about your weight, or a workout turns up with no name on it, it asks you. Two taps, and it tells you what your answer changed.
It asks first.
The coach asks before any of your training leaves the phone. Say no, or turn it off later in the You tab, and your day, your week and your workout readings are still written for you on the phone.
Your health records stay on your phone.
You choose what Metrion is allowed to read, and there is no account to open. The coach asks before it sends anything, and if you say no, everything you rely on keeps working, written on your phone and sent nowhere.
06 / Everything else that changes a week
It understands
the rest of it.
Heat, illness, travel, the gear in your hallway and your cycle all change what a week should ask of you. Metrion reads what it can, asks you about what it cannot, and tells you when it is guessing.
Your easy days are never taken away.
When you have been working hard, the hard sessions get shorter and the easy ones stay exactly as they were. Easy work is not what is tiring you, and it tells you so.
Strength with the gear you already own.
Tell it once what you have, whether that is nothing, a pair of dumbbells, a bar or a gym membership, and every session after that is one you can actually do.
It knows a row from a yoga class.
Eighteen kinds of workout, each read on its own terms. A swim comes with no heart-rate target, because your watch cannot read one properly underwater, and it tells you that rather than guessing.
It reads the air before you go out.
One line: what it feels like out there, and how much slower to go for the same effort. When it is hot enough to matter, it says to take that one indoors.
A cold does not undo your year.
Say you were ill, injured, away or stopped for a while. Those days stop counting against you, and the plan knows what coming back should look like.
Your cycle, if you want it.
Off until you turn it on. Then a higher resting heart rate in the second half of your cycle reads as your cycle rather than as bad recovery, and you can ask for a lighter week around your period.
It starts from what you already do.
If you are three weeks in, it will not hand you intervals, while two years of running gets them in week one, at a volume you already handle.
It shows its working.
Your fitness age names the study it was measured against, and says where someone like you does not fit it. Nothing is presented as fact that is really a guess.
Two things it cannot do yet.
Neither of these is in the app, and we would rather say so here than let you find out after you install it.
A guided walk-run.
Couch to 5 km, handed to you session by session. Today you get a week sized to suit you instead.
A hotel room and thirty minutes.
It knows the gear you own at home. It cannot yet take a sentence like that one and reshape the day around it.
BEFORE YOU INSTALL IT
The questions
we get asked.
What is Metrion?
Metrion is a training app for iPhone. It reads the workouts and health data your phone already keeps, builds a week of training around them, moves that week when your life moves, and gives you a coach you can ask about any of it.
What does the coach actually do?
You can ask it anything about your own training, such as how this month compares with last, what a session two years ago did for you, or why your week changed. It answers in plain words, draws a chart when that is clearer than a sentence, and every number it gives you comes from your own record and is checked against it before you see it.
What leaves my phone?
Nothing, until you say yes. When you set up, Metrion asks whether the coach may send out a short summary of your training. If you agree, that summary and any question you type go through Metrion's own server to Claude, the AI model made by Anthropic, which writes the coach's words. They carry no name, no email address and no account, because the app has none, and Metrion's server keeps none of it. Once a week the app also adds your workout count, minutes and distance to totals that name nobody. Say no, or turn the coach off later in the You tab, and nothing is sent. Your day, your week and your workout readings are still written for you on the phone.
Do I need to change how I track?
No. Keep the watch and the apps you already use. Metrion reads what is already in Apple Health, and you choose what to share with it.
Is it just for runners?
No. Walking, hiking, cycling, swimming, rowing, strength and more, each read on its own terms. Your own history decides what the week asks of you, so a walker is never told to run.
Does it handle the menstrual cycle?
If you want it to. Turn it on, and a higher resting heart rate in the second half of your cycle reads as your cycle rather than as poor recovery. You can ask for a lighter week around your period. It stays off until you choose it, and it tells you when your data is not regular enough to use.
What is free, and what is paid?
The free app is the whole app. The coach reads every workout you record, writes your week and answers up to a hundred and twenty questions a month. Metrion Plus reads each workout in more detail, writes your weekly verdict with the strongest coach available, and gives you a fresh count of a hundred questions every day rather than once a month. Either way every reading tells you who wrote it, and if you run out in a month your phone writes it and says so.
How do I get it?
Install it today through TestFlight, using the button at the top of this page. It is free while the beta runs, it needs an iPhone, and the Apple Watch app comes with it. It is not on the App Store yet. The examples on this page use made-up data.
The beta is open
Get it on your phone today.
Free while the beta runs. Metrion reads what is already in Apple Health, so there is nothing to set up.
Open TestFlight
OPEN THIS ON YOUR IPHONE · TESTFLIGHT DOES THE REST