The pace24 Journal
Training, with context.
Practical notes on endurance training, recovery and making sense of your data. From the team building pace24.
Featured story
November 2026
Training
Our Planner Followed Its Own Rules. The Athletes Lost Fitness.
We ran our season planner on made-up riders who never skip a session. Delivery was near perfect and fitness still fell. Then we graded all 172 limits in the engine against their sources.
The pace24 team5 min read
Latest in the Journal
9 articles
How pace24 Works
The Coach Moved Your Workout Before You Said Yes
An audit of our own chat found that some requests changed your calendar and pushed a new workout to your device before you saw it. Here is what we found and what a tap means now.
7 Nov 2026 · 5 min read
The pace24 teamRead articleHow pace24 Works
A Streak for a Sport Where Rest Is Part of the Plan
Duolingo says streaks bring people back. Training has rest days, illness and plans that change. Here are the rules we gave our streak and the score beside it, and what we have not tested.
7 Nov 2026 · 5 min read
The pace24 teamRead articleHow pace24 Works
The Coach Offered a Lighter Week It Could Not Build
After a break, a normal plan asks for more than your fitness now carries. Our coach says so and offers an easier week. Testing found it never read its own notes, and could not build the week it offered.
7 Nov 2026 · 7 min read
The pace24 teamRead articleHow pace24 Works
What If the Test Is Wrong, Not the AI?
Five times in one project, a bad number came from our own measuring stick instead of from the coach. Fixing two of them moved our headline score from about 31% to 55% without changing a single line of the coach.
2 Nov 2026 · 6 min read
The pace24 teamRead articleHow pace24 Works
A Chatbot Beat Qualified Trainers on Nine Questions. Does That Make It a Coach?
Ghent University had 27 blinded graders score ChatGPT against working personal trainers. The chatbot won six of nine questions and lost none of them. We read the paper, changed how we test our own coach because of it, and think the gap it leaves open is the entire job.
2 Nov 2026 · 8 min read
The pace24 teamRead articleRecovery
Oura, WHOOP or Garmin: How Accurate Is Your HRV?
Your ring says 82, your watch says 54. How accurate are Oura, WHOOP and Garmin at measuring HRV, and how do you use a noisy recovery score?
16 Oct 2026 · 6 min read
The pace24 teamRead articleHow pace24 Works
What Happens When You Test an AI Coach Instead of Trusting It?
We put AI models through coaching tasks on made-up athletes and measured what happened. Some results flattered the idea. Others did not.
16 Oct 2026 · 7 min read
The pace24 teamRead articleTraining
Does Consistency Really Beat Intensity? We Went Looking for the Trial
Everyone says show up more often and go hard less often. We looked for the studies behind that advice. Some of it holds up. Some of it is a nice idea nobody has tested.
16 Oct 2026 · 7 min read
The pace24 teamRead articleHow pace24 Works
Can an AI That Never Writes a Word Read Your Coaching Messages?
Jev answers questions with a choice and a probability, never a sentence. Here is how it reads an athlete's message, how code uses its answers, and where it failed our test.
16 Oct 2026 · 6 min read
The pace24 teamRead article
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