A running coach that reaches out on its own and that you can talk to. It knows all of your training and builds the plan that takes you to your goal.
Today
Can we swap the long run and the easy run this weekend? I have a dinner clashing.
That works, I am swapping them. You still get a day between the quality session and the long run, so the structure holds.
TO RACE DAY
12 weeks · 44 sessions
HOLDING YOU BACK
Durability
DevelopYou do not need to open the app to know what to do. The coach writes before a session and again once the analysis is done, and speaks up when your resting heart rate or HRV sits outside your usual range. Need a session on another day? Just say so, and the week gets rebuilt around it.
Monday evening
Legs feel heavy today. Should I still do the quality session tomorrow?
Heavy legs midway through a heavy week are expected, and you have slept short three nights running. Keep today easy and see how the warm-up feels tomorrow. If the heaviness is still there we move the session a day and put something easy in instead.
Tuesday morning
Resting heart rate is back to its usual and variability looks normal again. Run the session as planned.
Tuesday after the session
The threshold session landed well. Pace held evenly across the blocks and the heart rate stayed where it should, which is exactly what we want this far into the build. You pushed the last block slightly, but not enough to cost you. Next time we add another.
Saturday morning
Long run today, with the last few kilometres at marathon pace. Eat properly beforehand and carry a drink.
Every run syncs from Intervals.icu, which gathers Garmin, Polar, Coros and Suunto in one place. Load and form are worked out over time without you filling anything in.
Intervals.icu
Load
Resting heart rate, HRV and sleep come from your watch, and illness or a niggle you log is weighed into the plan.
LATEST HRV
68 ms (yesterday)
Baseline 58–78 ms
Within range
LATEST RESTING HR
46 bpm (yesterday)
Baseline 43–50 bpm
Within range
Which days you can train and which races you are aiming at, so the week lands where you actually have time.
Week 38Sep 14–20
Every run is reviewed as soon as it syncs, and the whole picture is gone through every three months on Pro and every month on Elite. The coach estimates five performance factors from your data and names the one holding you back from the race you are aiming at.
Coach FartlekRunning coach
We are working toward the Amsterdam Marathon, and what decides that race for you right now is durability: the last miles, not threshold or the ceiling. The achilles sets the limit on how far the long runs can grow, so the way there runs through marathon pace late in the session rather than more kilometres.
The coach lays out the year up to your race as training blocks, and the weeks just ahead as finished sessions in your calendar. Every session comes with the coach's own words on what it is for.
Coach FartlekRunning coach
Now we put marathon pace on top of the base you built. The long runs grow towards 32 km with the last few kilometres at race pace.
The week lands in your calendar. Miss a day and the plan adjusts by itself.
The coach lays the plan and follows it up, but not everything is the coach’s call. Three specialists write in the same chat, each with their own area. Write to whoever you want. Ask the coach about something that belongs to someone else, and the coach brings that person in.
Strength coach
Exercises and technique in your strength sessions, how the load should progress, and the log after each session.
Running coach
Lays the plan and follows up every session. Decides what you train, and when.
Nutritionist
Food for the week around your training, and fuelling on long runs and races.
Physiologist
Measures your threshold and the other performance factors, and explains what the numbers mean.
A plan is easy to come by. The hard part is having someone follow it up week by week and change it when your life changes.
The right coach can be the difference between training hard and progressing smart. But human coaches have limited time, many athletes, and cannot stay close to every decision in your daily life.
Coach FartlekThey analyse data and generate plans, but often stop there. When life changes between workouts, the guidance can quickly become generic instead of personal.
Coach Fartlek stays on top of your training and recovery, but what you notice is that it gets in touch and that it answers. You can ask why a session looks the way it does, and if you say the week fell apart it gets rebuilt.
Read our AI running coach comparison →SELF COACHEDElite
Self coached is a mode for runners who want to own their week. The calendar gets a plan mode where you build the weeks, and the coach stops writing in them. Input arrives as suggestion cards in chat instead, and nothing is entered until you approve the line. Requires Elite.
How self coached works →Week 35 · Aug 24–30Valid until Sunday Aug 30
Threshold Wednesday: 4×8 → 3×8 min
First week after the rebuild: three blocks give the stimulus without digging a hole.
Long run Sunday: 16 → 14 km
+2 km a week on the long run is steep enough this soon after being ill.
New: Recovery Friday, 4 km
An easy jog the day after threshold makes the legs quicker. Zone 1, no pressure.
Coach Leo is reachable from Telegram and inside ChatGPT. A fair comparison of the alternatives and who suits whom.
29 Sept 2026Read article →Ranner connects the watch directly and adjusts the plan day by day. A fair comparison of the alternatives and who suits whom.
29 Sept 2026Read article →Two gels and a little sports drink in a four hour marathon come to perhaps 15 to 20 grams an hour. The recommendation is 60 to 90, and your gut can be trained to take it.
28 Sept 2026Read article →Coach Fartlek is a running coach that reaches out on its own and that you can talk to. It knows all your training, your health and your conditions, sees what is holding you back, and builds the plan that takes you to your goal. Running only, 5K to the marathon.
Yes. Coach Fartlek pulls your training history, fitness, and load data from Intervals.icu, so an account there is required to get started. Syncing happens automatically in the background.
Try seven days free from your first plan. Pro is then $8.49/mo and Elite $20.99/mo. Pro gets deep analysis every three months, Elite every month plus self coached. Without a subscription the coach goes quiet, but your calendar and data stay.
Coach Fartlek is available for both iOS and Android. Download it from the App Store or Google Play to get started right away.
Most AI coaches build a plan from your data and adapt it. Coach Fartlek also tells you what is holding you back from your race and builds the week around that. It gets in touch on its own, and you can talk to it the way you would talk to a coach.
Coach Fartlek is built for runners who take their running seriously and handles everything from 5K to the marathon. You set the distances you are targeting and the races you have planned, and the coach builds training blocks accordingly.
Yes. The self coached mode flips the roles: you build every training week yourself in the calendar while the coach reviews it, checks the load, and sends suggestions you approve line by line. Requires Elite.
7 days free from your first plan · then from $8.49/mo · cancel anytime
