Jeff Dean's Intense Workout Routine — and His $10B AI Startup Exit from Google

Jeff Dean, Google's legendary employee No. 30 and former chief scientist, has left the company after 27 years to co-found Discovery Loop, an AI startup aimed at automating scientific and engineering research. The startup is in discussions to raise $1 billion at a roughly $10 billion valuation — a striking debut for a company still in its earliest stages. Alphabet itself is a founding investor, and Google Cloud is a partner, meaning Dean's ties to his former employer remain intact even as he strikes out independently.

Dean's departure is part of a broader reshuffling at Google's AI division. Demis Hassabis transitioned from CEO of Google DeepMind to chair of the unit and chief scientist of Alphabet, while DeepMind CTO Koray Kavukcuoglu stepped up to run day-to-day operations. Dean also brought several prominent colleagues with him to Discovery Loop: longtime researcher Sanjay Ghemawat, as well as Oriol Vinyals and Quoc Le — a significant brain drain of senior AI talent from one of the field's most storied labs.

On a lighter note, Dean shared his weekly fitness regimen after a user spotted yoga on his packed calendar during his final day at Google's office, shared at the KDD Conference in Jeju, South Korea. The routine is formidable: two soccer games per week in a 25-and-over league, two gym sessions, two yoga classes, three to four 8-kilometer runs to work, three to four 8-kilometer bike commutes, and a longer run or ride on weekends. For joint protection during all that high-impact activity, Dean keeps it simple — cushioned running shoes replaced frequently, plus arch support inserts. His main vulnerability, he noted, is his ankles, battered by too many basketball sprains over the years.

Dean has long been the subject of Chuck Norris-style mythologizing inside Google, a testament to his engineering reputation built over nearly three decades. The workout data only adds to the legend — though the bigger story is what he builds next with Discovery Loop.