The single most important habit to develop if you want to be successful

Lemi Berhanu Hayle of Ethiopia crosses the finish line to win the mens race in the 120th Boston Marathon on Monday, April 18, 2016.
John Tlumacki | The Boston Globe | Getty Images
Lemi Berhanu Hayle of Ethiopia crosses the finish line to win the mens race in the 120th Boston Marathon on Monday, April 18, 2016.

There's no universal predictor of success but focusing on one habit could increase your odds.

"Dozens of studies show that willpower is the single most important keystone habit for individual success," reports Charles Duhigg in his New York Times bestseller, "The Power of Habit."

As an example, Duhigg cites a 2005 University of Pennsylvania study that found that students with stronger willpower were more likely to get better grades and be admitted into selective schools.

"Highly self-disciplined adolescents outperformed their more impulsive peers on every academic-performance variable," the researchers concluded. "Self-discipline predicted academic performance more robustly than did IQ."

Willpower helps people succeed beyond the classroom. Other studies have found that as people improve willpower in one area of their lives — in the gym or with their eating habits — good habits then spill over into other parts of their lives, such as how they manage their money or perform at work, Duhigg reports.

"When you learn to force yourself to go to the gym or start your homework or eat a salad instead of a hamburger, part of what's happening is that you're changing how you think," Todd Heatherton, Ph.D., explained to Duhigg. "People get better at regulating their impulses. They learn how to distract themselves from temptations. And once you've gotten into that willpower groove, your brain is practiced at helping you focus on a goal."

The good news is willpower is a muscle, Duhigg explains. And like your biceps or abs, you can strengthen it.

The best way to do that is to make it a habit: Automate it.

Duhigg gives the example of Starbucks, which has devoted a lot of time and effort towards training its employees to exercise more willpower. The company "has dozens of routines that employees are taught to use during stressful inflection points," he writes. An inflection point could be an angry customer or a long line at the register.

"Throughout the training manuals are dozens of blank pages where employees can write out plans that anticipate how they will surmount inflection points," he continues. "Then they practice those plans, again and again, until they become automatic.

"This is how willpower becomes a habit: by choosing a certain behavior ahead of time, and then following that routine when an inflection point arrives."