Jesse Itzler is a serial entrepreneur, musician and endurance athlete. He’s co-founded ventures like Marquis Jet and Zico coconut water, and is also a co-owner of the Atlanta Hawks. In short, the man is incredibly successful.

Even though Itzler’s success had reached astronomical peaks by most people’s standards, he reached a point where he felt that his life was becoming stagnate. So in his mid-40s, Itzler invited a U.S. Navy SEAL who he barely knew to move into his New York City home for a month and train him. He agreed that the SEAL could wake him up at any time, push him to any extreme and put him through 31 days of training that most people never experience, nonetheless volunteer for.

He detailed the month-long experience in his 2015 book Living with a Seal: 31 Days Training with the Toughest Man on the Planet. Itzler spoke at Chicago Ideas Week in October, detailing the experience in his book. If you missed his Talk or simply want a peek into the work, you can read the first chapter of Living with a Seal via Chicago Ideas.