Can an AI Coach Build an Ironman?
I'm the Experiment.
On May 23, 2027 I'll participate in the Happy Valley, Pennsylvania Ironman 70.3 race, swimming 1.2 miles, biking 56 miles, and running 13.1 miles. To help me accomplish this unlikely feat, I built an AI coach named Apollo which is pretty much managing my life at the moment, including building and modifying my training schedule, adjusting my diet, as well as playing the role of cheerleader and at times acting like a complete jerk.
Who Is the Guinea Pig?
My name is Jason Gilmore, and I'm a computer nerd who had an existential crisis heading into 2025. I was overweight, tired all the time, and couldn't even keep up with my young children while playing soccer in the yard. Even more stressful was watching family members suffer from serious health-related issues at relatively young ages. I desperately wanted to avoid similar issues, particularly those which might be self-inflicted.
I decided to do something about it in the only way I know how: I created a spreadsheet. It worked. I got into absurdly good shape, and started running 5Ks and 1/2 marathons and getting into contests in which I would do more than 500 pushups in two hours. Then I started a race called the 5/15/500 Challenge. Then in 2026 I participated in my first weightlifting event (the Arnold Pump & Run) and set a new 5K PR (27:36), and then ran another 1/2 marathon. Much to my surprise I performed horribly in this race and went down a deep rabbit hole to understand why. That's when I wondered if I could use AI to help me not only become a better runner, but complete one of the most revered endurance races in the world: Ironman. And so here we are.
Why I'm Doing This
I wish I had a better answer to this question, because right now I am very, very sore. I suppose it is because ever since I was a teenager I always looked at Ironman competitors as the pinnacle of human performance. I thought of these people as gods among us, and still do. Even when I was terribly out of shape I always wondered what it would be like to be one of these people. I want to know if I can become one of them.
What Has Happened So Far
I started involving Apollo (again, that's my AI coach) on August 1. I have *a lot* of exercise-related data saved up from January 1, 2025 to July 31, 2026, and on August 1 I gave all of that data to Apollo and asked it what to do. It built a long term plan, and then started tuning my daily workouts based on the most recently available diet, sleep, heart rate, and previous activity data.
I still have a very long way to go, but the results over the past 30 days have so far been spectacular. Apollo is analyzing everything on a daily basis, repeatedly tuning my plan and adjusting accordingly when unexpected events come up (such as traveling for work). Apollo has also taught me so much about the importance of focusing on easy, long runs vs going all out every time, why I should be ingesting much more fat and protein on a daily basis, and even explaining what I should be eating ahead of particularly long workouts.
Follow Along
- Training diaryIrregular write-ups with the analysis behind each block.
- The full dashboardEvery number, updated after each sync. Fair warning: it's dense.