It was never part of Adam Hill's life ambition or his genetic constitution to wear a Speedo in public, let alone compete in a triathlon. For the first three decades of life, he was the poster child for non-athleticism, obsessively unhealthy habits, and an intense fear of...well...everything.

Yet at the age of thirty-three, with a physique that could only be described as "Sasquatch with a Dad Bod," he put aside his insecurities and took his first step toward an outrageous dream: to qualify for the Ironman World Championship in Hawaii.

It was a dream shared by nearly every other triathlete in the world, reserved for the top 1 percent of all athletes in the sport—a sport in which Adam had exactly zero experience.

In Shifting Gears, Adam shares his harrowing, inspiring, and sometimes-clumsy story of transformation, from the origins of a debilitating anxiety disorder to his battle with alcoholism to his rise to the top of the triathlon world stage.