Train for a T100 or 100km triathlon with an AI coach that knows all three disciplines.
Athmex keeps your FTP, run threshold, critical swim speed, race and training week ready for ChatGPT or Claude, so your AI can prepare you for a race that rewards sustained power and a strong run.
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What is a T100 or 100 km triathlon?
A 100 km triathlon is a 2 km swim, an 80 km bike and an 18 km run. It’s the format of the T100 Triathlon World Tour, where the professional races are held, and many T100 race weekends also include a 100 km race for age-group athletes.
It is not simply a slightly longer Olympic or a short 70.3. The swim is longer than Olympic, the bike is more than twice as long, and the run is close to a half marathon. Yet the whole thing is short enough to be raced hard throughout. For many age-group athletes that means several hours of hard racing.
- Swim
- 2 km
- Bike
- 80 km
- Run
- 18 km
- Total
- 100 km
Distances can be adjusted on individual courses, so check your race’s published details.
What ChatGPT or Claude needs for 100 km training
A useful 100 km triathlon training plan depends on how long you can hold a strong effort, so the AI needs your numbers and a clear picture of your durability.
- Race
- The event, date and course: flat and fast, windy, or with a technical city circuit.
- Bike
- Your current FTP and when it was set, how long you can hold an aero position, and whether you race a road or triathlon bike.
- Run
- Your threshold pace and recent half-marathon or 10K time, with dates.
- Swim
- Your CSS or recent 1,500 m time, and how comfortable you are over 2 km in open water.
- Fuelling
- What you’ve practised eating and drinking on long rides, and anything your stomach doesn’t tolerate.
- Availability
- Weekly hours, and which day can hold a long ride or long brick.
- Constraints
- Injuries, work, family and anything that limits a particular sport.
The 100 km problem
How do I ride 80 km hard and still run 18 km properly?
The 100 km format sits where threshold fitness and endurance meet. An 80 km bike leg is too long to ride at Olympic intensity and too short to ride as conservatively as a full-distance race. Much of the training conversation is about finding that effort and then proving, in training, that you can run well after it.
The right bike intensity depends on your current FTP, your run durability and the course. A plan that doesn’t know those three things is guessing at the most important decision of the race. With your numbers in Athmex, ChatGPT or Claude can build sessions that rehearse race effort and adjust them as your fitness changes.
Where 100 km racing happens
Race locations change from season to season. These three show the range of conditions an age-grouper might face.
- London
- London includes a 100 km race for age-group athletes alongside the wider T100 weekend. For UK athletes it’s an accessible way into the format, with no long-haul travel and a city course.
- Dubai
- A desert-city race where heat is part of the challenge, and a long flight for most European athletes. Heat, hydration and travel belong in the brief for this kind of race.
- Qatar
- Qatar hosts the 2026 T100 Age-Group World Championship, alongside the season-ending professional races. For an athlete chasing a championship result, it’s where the season ends.
Qualification for the age-group championship runs through designated 100 km races, and the rules are set by the organiser and can change between seasons. Check the current official championship rules for your event before building a season around qualifying.
Why 100 km isn’t just a longer Olympic
At Olympic distance an athlete can ride close to threshold for an hour and still run. Over 80 km that approach falls apart: the bike takes two hours or more for many age-groupers, and riding too hard costs far more on the run than it saves on the bike. Pacing becomes a discipline in its own right.
Training reflects that. More time goes into long intervals at race effort, and less into short, sharp work. The run is long enough that endurance from the bike carries straight into it.
Why 100 km isn’t just a short 70.3
Compared with a 70.3, the 100 km format is a little shorter on the bike and run and slightly longer in the swim. That small difference changes the intensity. Athletes tend to race it harder than a middle-distance race, so threshold fitness counts for more and conservative pacing costs more.
An athlete moving between the two needs different race-effort work, even though the weekly training looks similar. Tell your AI which one you’re preparing for.
Sustained cycling and aero position
The bike leg carries a large share of a 100 km race. Holding power in an aero position for two hours or more is a skill as well as a fitness test. Many athletes can produce the watts sitting up but lose them when tucked low. Long intervals ridden in race position, indoors or out, are central to the training.
The triathlon-bike world is full of machines like the Canyon Speedmax, Cervélo P-Series and Trek Speed Concept, but plenty of age-groupers race a road bike with clip-on bars. What matters for the plan is what you’ll actually ride and how long you can hold its position. Put that in your equipment notes.
Where threshold and endurance cross over
The 100 km format sits on the boundary between short-course speed and long-course endurance. You need a good FTP and run threshold, and you need to hold a high percentage of both for a long time.
That’s why current numbers matter. If your FTP is from last winter or your threshold pace is from a different season, the plan will set the wrong race effort. Athmex keeps each value with the date it was measured. The triathlon guide explains how to keep all three current.
Running strongly after 80 km
An 18 km run is long enough that you can’t get through it on adrenaline. The legs that come off an 80 km ride are tired, and a pace that feels easy in the first kilometre can be unsustainable by the tenth.
Long bricks are a useful rehearsal: a race-effort ride followed by a steady run, built gradually through the block. ChatGPT or Claude can place them around your long ride day and make sure there’s recovery either side.
Fuelling without full-distance volumes
Racing for up to five hours needs a proper fuelling plan, but it’s different from a full-distance race. The intensity is higher, which makes eating harder, and the time is shorter, which leaves less room to fix mistakes. Practising race fuelling on long rides and bricks is part of the training.
Your AI isn’t a sports dietitian and won’t replace one. But if Athmex knows what you’ve practised and what has caused problems before, it can build that practice into the right sessions.
Race-specific training for your course
A flat, hot desert course and a technical city circuit with tight turns reward different preparation. Heat needs acclimatisation. Technical courses need bike handling and repeated accelerations. A wetsuit or non-wetsuit swim changes the swim preparation too.
Store the course details in your Athmex race record and ChatGPT or Claude can make the final weeks specific to the race you’re actually doing.
Using your ride and run data for 100 km training
Long rides recorded on a Garmin or Wahoo computer, indoor sessions on Zwift and runs on a multisport watch hold useful detail about what you’ve done. Some platforms can share that data with ChatGPT or Claude through their own connection. Athmex doesn’t import it; it supplies your thresholds, race and constraints so the AI knows how to read it. See the available routes.
Give your AI coach what it needs to pace 100 km.
Build your athlete profile once. Connect ChatGPT or Claude. Keep your FTP, run threshold, CSS, race and weekly hours ready whenever you ask about training.
14 days free · then $6.99/month · cancel anytime