An AI triathlon coach for swim, bike, run and strength in one plan

One plan for three sports and the gym

Separate running and cycling apps each see half your week, so they happily give you a hard ride the day after a hard run. TextFit plans all of it from one athlete profile:

• Goal: a sprint, Olympic, half or full distance triathlon on a date, with an optional target time, or general fitness.
• Your week: 2 to 12 sessions, up to three days off, the longest session on a weekday and a weekend day.
• Current fitness per sport, in your own words: “10 km in 45 minutes”, “ramp test gave 230 W”, “100 m in about 1:50”. The coach reads threshold pace, FTP and CSS from them.
• Swim venue (25 m, 50 m or open water) and strength at a gym or at home.

After the AI consent and connecting Garmin or Apple Health, the coach builds your first two weeks and shows you the next 7 days. Start your 14-day free trial and they’re on your watch.

Hard days are counted across sports

A hard swim and a hard ride on consecutive days are two hard days in a row. A validator checks these rules in code:

Rule	What it means for a triathlete
Hard days	At most 2 a week, or 3 if you train more than 8 sessions, never on consecutive days. Swim sets, bike and run intervals, the long workouts and threshold tests all count.
Long weekend	A long ride and a long run on Saturday and Sunday, mostly easy, the run usually after the ride and shorter than a standalone long run. Together they count as one hard day.
80/20	About 80% of training time easy, across all three sports.
Strength	1 to 2 sessions of 20 to 45 minutes, after a mid-week key session or on an easy day; never the day before a key or long workout, so not on Friday. 1 light session in a taper week.
Doubles	At most 2 sessions a day: easy with easy, easy with strength, or a key session followed by strength.
Progression	Weekly volume grows by no more than 10%, with a recovery week (30 to 40% less) every 4th week.
Phases	Base, build, peak, then a 2-week taper before the race.

More on the rules and the validator: how the coach builds and adapts a week.

Example: an Olympic distance build week

An illustration for one athlete: Olympic distance in 14 weeks, 9 sessions including gym strength, Monday off, up to 90 minutes on weekdays and 3 hours at the weekend; run threshold 4:30 per km, FTP 230 W, CSS 1:50 per 100 m.

Day	Sessions	Steps and targets
Mon	Day off	No training.
Tue	Swim intervals · 35 min · hard Strength · 35 min	400 m easy @ 2:14–2:27 /100 m, 10 × 100 m @ 1:47–1:53 /100 m on a 2:05 send-off, 200 m easy Back squat, Romanian deadlift, split squat, push-up, plank: 3 sets each
Wed	Easy ride · 60 min Easy run · 30 min	60 min @ 129–173 W 30 min @ 5:29–6:00 /km
Thu	Run intervals · 50 min · hard	15 min easy, 5 × (3 min @ 4:05–4:20 /km + 2 min jog), 10 min easy
Fri	Technique swim · 40 min Easy ride · 45 min	Drills, then easy swimming @ 2:14–2:27 /100 m 45 min @ 129–173 W
Sat	Long ride · 2 h 30 min · hard	2 h 30 min @ 129–173 W
Sun	Long run · 60 min · hard	60 min @ 5:29–6:00 /km

• Three hard days, all apart: the swim set on Tuesday, the run intervals on Thursday and the long weekend, which counts as one. Nine sessions allow three; at eight or fewer there would be two.
• Strength on Tuesday, after the key swim: hard days hard, easy days easy. Friday is out because the long weekend follows.

For the sessions themselves, see triathlon interval training.

Unknown thresholds: CSS, FTP and run tests first

Swim paces come from CSS, bike watts from FTP, run paces from your threshold pace. When one is missing, week one has that sport’s test: a 400 m + 200 m CSS swim, an FTP ramp or 20 to 30 minute ride, or a 20 to 30 minute hard run. A sport you’re a beginner in gets no test for its first 4 weeks. Until there’s a result, hard work goes by heart rate or effort (“RPE 7–8”). Report it (“CSS test: 400 in 7:10, 200 in 3:25”) and the targets follow. The FTP test guide covers pacing the bike test.

What reaches your watch, sport by sport

The next 7 days go to your primary device automatically and are updated when the plan or a threshold changes.

Sport	Garmin (via Garmin Connect)	Apple Watch (via WorkoutKit)
Run	Structured workout with pace or heart-rate ranges per step	Custom workout with a pace or heart-rate range alert per step
Bike	Structured workout with power or heart-rate ranges, on a watch or bike computer	Custom workout with power or heart-rate range alerts
Pool swim	Pool length, distances, stroke, drill, equipment and send-off rests, with the CSS-based pace as each step’s target	Intervals with distance and send-off time (iOS 18 or later)
Strength	Exercises with sets, reps and weight, matched to Garmin’s exercise list where possible	A strength workout with steps like “Back squat · 8 · 80 kg”; you tap through the sets

Setup details: TextFit with Garmin and TextFit with Apple Watch.

Talking to the coach about a triathlon week

You write	What the coach does
“The pool is closed Friday, swap the swim”	Replaces that swim with another easy session and keeps a swim in the week, with Undo.
“Plan next week. Work trip Wednesday to Friday, hotel gym only”	Plans the week around your note and shows a week card with its reasoning.
“Ramp test today: 245 W”	Saves the new FTP. The watt targets on upcoming rides follow, on the watch too.
“Am I recovered?”	Compares last night’s HRV, resting heart rate and sleep with your normal range over the previous 28 nights: 🟢, 🟡 or 🔴. On 🟡 or 🔴 it offers Ease today.
“How’s my form?”	Fitness, Fatigue and Form across all sports, plus your completed workouts over 4 weeks.

Is it also an AI swim coach?

For pool training, yes. Pick a swim-only goal (1,500 m or 3,800 m) or swim as part of a triathlon. The coach writes structured pool sessions with CSS-based paces, send-offs, strokes and drills, schedules a CSS test when it doesn’t know yours, and for a swim goal predicts a time from your CSS.

AI triathlon coach, human coach or a static plan?

	TextFit’s AI coach	Human coach	Static plan
Cost	14 days free, then $14.99/month or $99.99/year	A monthly fee, often $100 to $300	Free or a one-off price
When the week changes	One message; sessions move or ease under the same rules	As fast as your coach replies	You decide what to drop
Workouts on the watch	Next 7 days pushed to Garmin or Apple Watch	Depends on the coach’s platform	You build each one

Running only? See the AI running coach.

Questions about the AI triathlon coach

Can an AI coach plan triathlon training?

Yes, within rules. TextFit’s coach plans swim, bike, run and strength in one week from your race, days and current fitness, counts hard days across all sports, and a validator checks every week in code.

Which triathlon distances can I train for?

Sprint, Olympic, half distance and full distance, each with a race date and an optional target time. You can also train for general fitness across the three sports.

What if I don’t know my CSS, FTP or threshold pace?

The coach schedules a test in week one for each sport it lacks: a 400 m + 200 m CSS swim, an FTP ramp, a 20 to 30 minute hard run. A beginner sport gets no test in its first 4 weeks; until there’s a result, hard work goes by heart rate or effort.

Does strength work show up on my watch?

Yes. On Garmin each exercise arrives with its sets, reps and weight; on Apple Watch it’s a strength workout with steps named by exercise, reps and load.

Can I use a Garmin and an Apple Watch together?

Yes. Your primary device gets the automatic pushes, and its data wins when the same workout arrives from both.

How much does it cost?

The first 14 days are free. After that it’s $14.99 a month or $99.99 a year (US App Store prices), and you can cancel anytime in your App Store settings.

Trial, data and account questions are answered in the FAQ.