Other billionaires, including Richard Branson, Mark Zuckerberg and Mark Cuban, agree that exercise is key to success.
"I seriously doubt that I would have been as successful in my career (and happy in my personal life) if I hadn't always placed importance on my health and fitness," Branson writes on his blog. He prefers to play tennis, go biking, run and kite surf.
Zuckerberg prioritizes exercise because, as he said in a Q&A on Facebook, "Doing anything well requires energy, and you just have a lot more energy when you're fit."
As for Cuban, he always tries to get in an hour of cardio, six or seven days a week. It fuels his competitive spirit, he tells Dallas News: "[I] have to go longer than anyone who started before me." His dedication to exercise is like his commitment to business, he adds: "That I will find a way to get [a workout] done, I think, reflects how relentless I can be in the business world as well."
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