Antonio Horta-Osorio, chief executive of Lloyds Banking Group, lists cage diving with sharks as one of his hobbies.
London Stock Exchange chief executive Xavier Rolet gets his drive from competing in the Paris-Dakar motor sport rally.
Mark Bristow, chief executive of gold mining group Randgold, revs up on mammoth 30-day, 5,000-mile motorbike rides across Africa.
Rune Sovndahl, co-founder and chief executive of global domestic services provider Fantastic Services goes cave-diving
Meanwhile, James Reed, Chairman of Reed Recruitment, gets his buzz from beekeeping, going so far as to install a hive on the top floor of the firm's Covent Garden office.
Are our chief executives, conventionally viewed as conservative accountancy types, actually a bunch of reckless risk-takers who need the release that hazardous hobbies provide to allow them to get on with their day jobs?
Perhaps this is true for some. However, rather than singling them out as quirky or unusual, could the peccadillos of our CEOs actually act to "normalise" them and save them from being total work-obsessed compulsives?
Most CEOs are certainly not as cold and calculating as they can appear.
Some identify particular weaknesses that they get help to address.
One former chief executive of a FTSE100 financial services giant once told me that he hired an actress to come into the group headquarters each month to teach him how to act out the CEO role.
"I am a very shy individual," he said. "I would not normally engage with people. It's just a management style I have developed over the years.
"We all put on a show. We are all actors and I have learned to act. The actress comes in and coaches me in body language, presentation style and public speaking.
"I am an introvert and introverts get drawn in. I don't need to have a high regard for friendships or closeness. I can retain my intellectual distance with the people who work for me."
A former CEO of a FTSE100 property company confessed to bringing a singer into group headquarters for much the same reason.
"It's very difficult for someone like me who's quite reserved," he said, "because I have to talk to a lot of people outside the business and to stakeholders so it's very challenging.
"I work with a voice coach who is an actress. She says, for example: 'What emotion do you want to convey?' and I say that maybe I want to convey more emotion in a presentation. She teaches me to do it."
Are these CEOs dysfunctional leaders or are they just human beings admitting their vulnerability and taking action to equip themselves for their demanding roles?
Sovndahl argues for the latter, saying entrepreneurs' brains are so absorbed with work that they need to be in “seemingly stressful” situations to relax.
Each to his or her own. In reality, of course, practical realities such as "key person" insurance policies often mean that CEOs don't get to indulge their risk-taking in their spare time as much as their biogs might suggest.
Shareholders might be glad of that. So when the last time that Horta-Osorio actually dived with sharks? Does he have to declare it as a material risk? Group risk management and compliance might be about to get a lot more interesting.