These Founders (Really) Fight

Alex Tehrani
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"Life-Changing Level of Physical Exertion"

"Being in the ring with another person trying to hit you for one minute is a totally life-changing level of physical exertion. It's everything you can do to stay standing when you're done," says Philip Rosedale (pictured), the serial entrepreneur behind Second Life, who is now working on a new start-up called High Fidelity. He's been boxing for three years, and says that in that time he's come to recognize fear--in and out of the ring. "Now I can say, 'Wow, I'm afraid of my board member right now, and I'm not reacting in a way that's productive for this company.'"