The Work: In a word, juggling. At least in the beginning, you'll need to balance a day job to pay the bills, a minimum of 25 hours of training a week, a grueling weekend race schedule, quality face-time with potential sponsors, and sleepless nights agonizing over your decision to abandon a respectable living for this.
Time Outside: 35-60 percent. You've got to play (and practice) to win.
Payback: If you can break even, you're doing pretty damn well; avoiding debt usually requires deep-pocketed sponsors. Expect to bank $20,000-$30,000 in a good year, unless you're wildly successful (surfing great Kelly Slater boasts career contest earnings of more than $700,000).
Prerequisites: Athletic genes and a high tolerance for prerace jitters will take you only so far. Make sure your competitive streak runs strong and deep. "You have to be more than a gifted athlete," says extreme kayaker Tao Berman, whose world-record 98-foot waterfall drop speaks for itself. "You have to be cutthroat ambitious."
Networking: Start trouncing the local competition, and then launch a full-scale sponsorship blitz: mass résumé mailings, cold-calling, and chatting up athlete reps.
Peon to Pro: Master your signature move—like Berman's ten-story plunge—and flaunt it shamelessly.
Drudge Factor: Waking up sore before the 42-mile Rage in the Sage bike race after a night in budget accommodations: your tent.
Outlook: Keep sucking up to your day-job boss and scrambling for sponsorship. Competition is fierce.