Life becomes complicated when you realize that the motivation to start or delay a task is a tug-of-war between positive and negative emotions. Don’t blame lack of willpower, laziness, or low motivation if you aren’t achieving your goals.

Motivation is not a skill. Like a muscle, it’s subject to fatigue when stretched. That’s why fascinating research in the field of psychoneuroimmunology has revealed another reason you may feel paralyzed to take action—one with the potential to dramatically transform your life.

In this completely updated edition of Dr. Nick Hall’s popular book, he shows you how to unlock the biochemical code that will free you to easily achieve any goal in life. And while the biochemistry may be complex, the solutions are actually quite simple.