Is AI coaching actually effective for endurance training?

The training science is the same math coaches already use: load, fatigue, and form computed from your completed workouts, periodized toward your race date. What the AI adds is speed. With a watch connected, it reads your HRV, sleep, and recovery every day and adjusts the plan instead of waiting for a weekly check-in, and every adjustment shows its reasoning so you can judge it the way you would a coach's call.

Why is Athlete Space free?

Athlete Space is built and run by one athlete-engineer, and keeping it free is the point: every athlete should have a coach that adapts. No ads, and we never sell your data. Fair-use limits on coach chat and form analysis keep the running costs in check, so it stays free for everyone.

How does the AI decide when to change my plan?

Every night it checks tomorrow against what you did, your check-in and your recovery data. Small changes it makes and tells you why, and you can undo any of them; bigger ones come to you as a proposal.

Can I use Athlete Space inside Claude or ChatGPT?

Yes. Add the free Athlete Space connector and ask for a plan in the chat: a running plan from 5K to marathon, or a triathlon, HYROX, cycling, swimming or CrossFit season. No account is needed, and you can open the plan on Athlete Space to keep it adapting.

Is my health data secure?

Data is encrypted in transit and at rest. Connections to Garmin, Strava, and other services use OAuth, so we never see those passwords, and we never sell or share your data. You can disconnect any integration or delete your account and all of its data from Settings at any time.

What if I already use another app or a human coach?

They work well together. Athlete Space reads from the same watches and apps, so you can use it next to another training app and see the calls your coach makes. Athletes with a human coach use it between check-ins, and if you're coming from another platform, you can bring your workout history with you.

Do I need a smart trainer or a special treadmill?

Any treadmill works: the app gives you the belt speed for each step, and a watch or footpod can correct a belt that reads fast or slow. For ERG and sim on the bike you need a smart trainer that connects over Bluetooth.

Can I use my TV or laptop as the workout screen?

Yes. There is an Apple TV app and a Mac app, and on a Windows PC or a Chromebook you can open athletespace.ai/desktop in Chrome or Edge. Your session fills the screen in the colour of the effort you are in.

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FREE AI COACH · 7 SPORTS FREE AI COACH · 7 SPORTS · NO CARD

A coach that
follows you.

Miss a run or sleep badly: your coach notices and tomorrow changes. Free, no login to start. Miss a run, sleep badly or feel great. Your coach notices, tells you why, and tomorrow changes. Free, no login to start.

The week in Athlete Space: Thursday moved, today a 70-minute threshold session

What are you training for?

Build my plan

Free. No login. Your first week in 60 seconds.

120,000+ workouts analyzed42 countries5.0 on the App Store

Prefer to chat? Athlete Space also works in ChatGPT and Claude. See how

Just looking? See a sample plan

TODAY CHANGED · 6:02 AM

Thursday's run moved. I made today a threshold session, and Sunday's long run stays.

70 min Load 87 · today

SYNCS WITH WHAT YOU ALREADY WEAR

Your devices. One plan.

GARMIN
STRAVA
Apple Health
Samsung Health
ŌURA
WHOOP
POLAR
wahoo
Intervals.icu
Google Calendar

No watch? Record runs, rides and workouts with the Athlete Space app on your phone or Apple Watch.

Use in Claude Use in ChatGPT Other AI assistants

HOW IT ADAPTS

Life happens. Your plan rewrites itself.

Three mornings, three changes. Each time your coach decides, and tells you why in one sentence.

A bad night

Sleep 5h 40m
HRV −9% vs baseline
Readiness 58

YESTERDAY'S PLAN

6 × 800 m @ 5K pace

52 min · Load 78

TODAY, AFTER CHECK-IN

Easy 40 min + strides

40 min · Load 31

Why: you slept 5h 40m. The hard session moves to Thursday.

A missed run

Tuesday tempo skipped
Work trip

THE WEEK AS PLANNED

Tempo Tue · Easy Thu · Long Sun

One key session gone

THE WEEK, RE-BALANCED

Tempo Thu · Easy Fri · Long Sun

Same key work, race date unchanged

Why: one missed day is not a missed week. The tempo still fits before Sunday, so the race stays on track.

A great day

Slept 8h 10m
Every rep on target last week

YOU ASK THE COACH

“Can I push today?”

Planned: 4 × 6 min at threshold

TODAY, UPDATED

5 × 6 min at threshold

One more rep than planned

Why: you earned it. One extra rep today, and tomorrow stays easy so the gain sticks.

Planning in Claude or ChatGPT? Tell it about a missed run and the plan rebuilds there too

Bruno Artacho racing the St. Jude Memphis Marathon

FROM ONE ATHLETE TO ANOTHER

Made by someone who's been where you are.

Husband, dad of a 2-year-old and a baby. I know the early alarms and the weeks when life wins. I built the coach I wanted for those days.

Bruno Artacho, founder · Nashville, TN

2:29 marathon · 9:01 Ironman · PhD in AI

Why I built Athlete Space

IPHONE · IPAD · WATCH · TV · MAC

One coach, every screen.

Start on the TV, check in on your phone, finish on your wrist. Free on all five.

Download on the App Store Get it on Google Play

Athlete Space on Apple TV, Mac, iPad, iPhone and Apple Watch, each showing the same athlete's training

NEW TO THIS? START HERE

No race, no watch? Perfect.

Tell us how much you move today. The plan starts there and grows with you.

NOW IN CHATGPT AND CLAUDE

Ask your AI for a real plan.

Tell ChatGPT or Claude your race, what you run in a week and how many days you can train. Athlete Space builds every week and session right in the chat, with paces from your current fitness. Free, no account.

Tap a prompt to copy it

Open ChatGPT How to set it up

Example · ChatGPT

You

Build me a half marathon plan for March 15. I run 20 miles a week, 4 days a week, easy pace 9:45.

Your 12-week half marathon plan

12 weeks · 4 days a week

Week 5 · key session

4 x 5 min cruise intervals, 46 min

Warm-up: 10 min easy warm-up at est. 9:47-10:22/mi, effort 3-4 of 10 (easy, then 4 x 20 s relaxed strides)
Main set: 4 x (5 min cruise interval at est. 7:41-7:59/mi, effort 7-8 of 10 (strong but controlled, not racing); 60 s easy jog at est. 10:22-10:59/mi, effort 2-3 of 10).
Cues: The first rep should feel controlled, almost easy; threshold is hard but steady, not a race.

Open in Athlete Space →

AI COACH

A coach that knows your data. And runs with you.

Ask it anything, right here: why today is easy, how to fit training around a work trip. Record in the app and it talks you through the session in real time.

Your coach also builds a route for today's session and calls every turn.

Athlete Space coach

Ask it anything. No account needed.

I'm the Athlete Space coach. Tell me what you're training for and where you're stuck, and I'll tell you what I'd actually do.

Real answers from the real coach. No signup, no card.

Treadmill recording screen: set the belt to 10.8 mph, rep 1 of 4 — Runs the treadmill and the trainer A belt speed for every step. ERG holds your power. Can't hold it? One tap eases the session.Open the big-screen app

Runs the treadmill and the trainer A belt speed for every step. ERG holds your power. Can't hold it? One tap eases the session.Open the big-screen app

Coach tab during a treadmill session: interval 1 of 4, belt at 10.8 miles per hour — Talks you through every rep Record in the app and it calls the session out loud. Tell it “too hard” and it adjusts.

Talks you through every rep Record in the app and it calls the session out loud. Tell it “too hard” and it adjusts.

Form analysis screen: film a few seconds from the side — Film 10 seconds of your stride 17 body points from a phone clip, then drills added to your plan. Free.

Film 10 seconds of your stride 17 body points from a phone clip, then drills added to your plan. Free.

One coach. Seven sports.

Pick yours to see a real plan.

EVERYTHING INCLUDED · FREE

Replaces the apps you open every morning.

Plan

Adaptive race plans
Periodized to race day
Season roadmap
A, B and C races, base to taper
Strength built in
Lifts that fit around key sessions
Together sessions
In sync, each at your own targets
Routes built for the session
With turn-by-turn voice

Coach

AI coach chat
Knows every session you've done
Morning check-in
Readiness score in 10 seconds
Voice coach on runs
Record with HR, power, cadence
Form analysis
17 points from a phone clip
Treadmill and trainer modes
Belt speeds, ERG, sim, FTP tests
Race mode
Pace cues to your goal time

Analyze

Fitness, fatigue, form
Performance chart, exportable
Race predictions
Plus a pacing strategy
Session verdicts
Planned vs done, every workout
Race recap + Wrapped
Shareable month and year

Connect

Workouts to your device
FIT, ZWO and ERG files for most watches and trainers
Apple Watch, Apple TV, Mac
One plan on every screen
Calendar sync
Sessions in Google Calendar
TrainingPeaks import
Bring your history. Use in Claude too
Samsung Health
Through Health Connect on Android

Ask the AI coach Try it now, no account Runs with you Live voice feedback when you record

Form analysis 17 body points from a 10 s clip Train indoors Treadmill, trainer, together

Plan Race plans · season · strength

Adaptive race plans
Periodized to race day
Season roadmap
A, B and C races, base to taper
Strength built in
Lifts that fit around key sessions
Together sessions
In sync, each at your own targets
Routes built for the session
With turn-by-turn voice
Morning check-in
Readiness score in 10 seconds
Race mode
Pace cues to your goal time

Analyze Fitness · predictions · recap

Fitness, fatigue, form
Performance chart, exportable
Race predictions
Plus a pacing strategy
Session verdicts
Planned vs done, every workout
Race recap + Wrapped
Shareable month and year

Record + connect Watch · TV · Mac

Workouts to your device
FIT, ZWO and ERG files for most watches and trainers
Apple Watch, Apple TV, Mac
One plan on every screen
Calendar sync
Sessions in Google Calendar
TrainingPeaks import
Bring your history. Use in Claude too
Samsung Health
Through Health Connect on Android

PRICING · COMPARED

$0, every sport. Here's why.

No ads. Nothing in the app is there to sell you something.
No data sales. Your training and health data are never sold or shared with advertisers.

US list prices as of September 2026 · see sources

What Athlete Space and five other training apps include, and what they cost a year
APP	PER YEAR	FREE VERSION	SPORTS	FORM ANALYSIS	COACH YOU CAN ASK
Athlete Space	$0	Everything	7 sports	Yes	AI, any time
Runna	$119.99	7-day trial	Running	Not listed	Not listed
TrainingPeaks	$134.99 + plans	Logging only	Multi-sport	Not listed	Human, paid extra
AI Endurance	$200	14-day trial	Run, bike, tri	No	Yes
Garmin Coach	$0 with a Garmin	Free with a Garmin watch	Run, bike, tri	Not listed	Not listed
TriDot	$180–$2,988	None	Triathlon	No	Human, paid extra

“Not listed” means not shown on their home or pricing page.

$0 no card · no trial clock

Every feature, every sport, coach chat and form analysis included. No ads, and we never sell your data. Fair-use limits keep it free for everyone. Built by one athlete-engineer in Nashville.

Build my free plan Full side-by-side comparisons

$0 no trial · no card · made in Nashville

Runna: $119.99 /yr
TrainingPeaks: $134.99 /yr + plans
AI Endurance: $200 /yr
Garmin Coach: $0 with a Garmin
TriDot: $180–$2,988 /yr

US list prices as of September 2026 · sources

Straight answers.

Still unsure? Ask the coach above. It answers without an account.

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Pick a race. Free. No login. Your first week in 60 seconds.

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