Book a DemoHarlen reads every signal a client produces, wearable data, lifestyle, training, and the notes you log, into one connected model. Then it hands you the read: who needs attention, what changed, and what to adjust.
Great personal trainers already think this way. They hold every client’s history in their head and adjust on instinct. That doesn’t scale past a handful of people, and the signal gets lost the moment a roster grows. Harlen is the instrument that keeps that judgment sharp across every client, every week.
Not a dashboard to interpret. Not a chatbot bolted onto a database. A single intelligent system that reasons over the whole client and shows its work, grounded in their own baseline and in peer reviewed research.
Harlen was co-founded by Kai Morales and Daniel Nguyen. Kai studies Economics at the University of Pittsburgh; Daniel studies Computer Science and Math at the University of Virginia. Both are still in college. The product is built at VO2 Labs, LLC.
We recommend a quick demo before you commit. Twenty minutes with a founder. We’ll show you exactly what Harlen looks like for a gym like yours. No client data needed.
$149/mo + $6 per client · first 10 clients free