There’s an old saying among professional boxers: “Champions don’t become champions in the ring; they are merely recognized there.” The implication, of course, is that the hard work of winning happens during an intense training regimen. The blood, sweat, and tears on the gym floor; the relentless planning for every possible scenario; the sacrifice and careful preparation. This is the stuff that ultimately enables victory.

Professional athletes achieve at the highest levels by spending 90% of thei...