Rather, to change a habit, you must keep the old cue, and deliver the old reward, but insert a new routine.

There’s something really powerful about groups and shared experiences. People might be skeptical about their ability to change if they’re by themselves, but a group will convince them to suspend disbelief. A community creates belief.

If you dress a new something in old habits, it’s easier for the public to accept it.

What studies say the number one best way to start an exercise habit is to give yourself a reward that you genuinely enjoy.

Typically, people who exercise start eating better and becoming more productive at work. They smoke less and show more patience with colleagues and family. They use their credit cards less frequently and say they feel less stressed. It's not completely clear why. But for many people, exercise is a keystone habit that triggers widespread change.

If you want to do something that requires willpower - like going for a run after work - you have to conserve your willpower muscle during the day.

Most of the choices we make each day may feel like the products of well-considered decision making, but they’re not. They’re habits.