Hey everyone,
I’m a father of two, train for marathons and Ironman-distance triathlons, and like many age-group athletes I have a fairly normal problem: I don’t have unlimited time, my weeks rarely go exactly to plan, and a private coach is hard to justify financially.
Some weeks a kid is sick. Some weeks I’m sick because a kid was sick. Sometimes work runs late, sleep is bad, or the planned long session just does not fit anymore.
I tried a lot of training apps and plans, but I kept running into the same issue: most plans work well as long as life behaves or are just not good UX. The moment a few sessions are missed, the plan either becomes unrealistic, creates a “catch-up” spiral, or leaves me guessing what to do next.
So I started building RaceMind.
The idea is simple:
A training coach for marathon and triathlon that adapts when real life gets in the way — without blindly pushing you into more load.
Why the plan engine is not AI-generated
This is probably the most important design decision.
RaceMind does use AI for coaching, explanations, chat, analysis, and helping you understand what is going on in your training.
But the actual training plan generation is deliberately not generated by an LLM.
I tested that approach early on, and for me it was either:
- too unreliable when it was fast, or
- too slow and over-engineered when I tried to make it reliable enough.
For training plans, especially when fatigue, progression, injuries and missed sessions are involved, I wanted something more deterministic.
So the plan engine is rule-based and built around clear constraints:
- controlled weekly load progression
- no aggressive catch-up logic after missed workouts
- conservative return-to-training after illness or injury
- phase-based structure: base, build, peak, taper
- sport-specific logic for running, cycling, swimming, strength and mobility
- availability-based weekly planning
- adaptations when the week no longer matches the original plan
The AI sits on top of that system as the coach interface — explaining decisions, answering questions, helping you adjust the plan, and giving context after workouts.
But the safety-critical part of “what should be scheduled next?” is not just an LLM making things up.
What RaceMind does
RaceMind is built for runners and triathletes preparing for:
- half marathon
- marathon
- middle-distance triathlon / 70.3
- long-distance triathlon / Ironman
- Ultra running (in preparation, happy to hear feedback for it)
Some of the main features:
- adaptive weekly training plans
- automatic replanning when sessions are missed or moved
- coach chat that can actually change the plan, not just talk about it
- post-workout analysis in plain language
- readiness guidance based on recent load, sleep/recovery data where available
- conservative comeback logic after sickness or injury
- race-day pacing and nutrition guidance
- structured workouts that can be sent to your device
- goal-time forecasting that updates as more data comes in
The main problem I wanted to solve was not “give me more data”.
Intervals.icu already does a great job with data.
The problem I wanted to solve was:
What should I actually do now, given my goal, my current fitness, my fatigue, and the fact that my week just changed again?
Why Intervals.icu matters here
I really like Intervals.icu.
Honestly, without Intervals.icu I probably would not have started building RaceMind in this form. It gave me a much better foundation for understanding training load, history and athlete context than most platforms.
That is also why I would love feedback from people here specifically. This community understands training data, but also knows where data alone is not enough.
Free for Intervals.icu users
As a thank you to this community, Intervals.icu users can test RaceMind free for 3 months.
Use this link/code: INTERVALSICU
No pressure to continue after that. I’m mainly looking for honest feedback from people who actually understand structured endurance training.
Website is here:
What I’d love feedback on
I’d be especially interested in your thoughts on:
- Would you trust a rule-based plan engine more than an AI-generated plan?
- What safeguards would you expect before an app changes your training plan?
- What should happen after missed workouts: skip, replace, reduce, or replan?
- How conservative should a return-to-training flow be after illness or injury?
- I’m also considering adding ultra running support. To me, that seems different enough from marathon planning that it should not just be “marathon plan, but longer”: elevation, durability, back-to-back long runs, fueling, hiking/walking strategy, and more conservative load progression probably matter much more. Would people here find that useful, and what would you expect from a good ultra plan?
Happy to answer questions, and also happy to hear criticism. I’m still actively building this and would rather learn from experienced users early than continue in the wrong direction.
Thanks,
Dominik
