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The science of willpower

The science of willpower

1-28-13: In this new piece, McGonigal answers additional questions about the latest research on willpower and how readers can use those insights to achieve their goals.


12-29-11: Contrary to popular belief, willpower is not an innate trait that you’re either born with or without. Rather it’s a complex mind-body response that can be compromised by stress, sleep deprivation and nutrition and that can be strengthened through certain practices. In a just-published book based on her popular Stanford Continuing Studies course, Stanford health psychologist Kelly McGonigal, PhD, took a closer look at the science of willpower and examined the latest research on the topic. In the Q&A below, she shares some of her thoughts.

Is willpower in the mind or the body?

Both! Psychologists have found that willpower is a lot like stress: It’s not just a psychological experience, but a full-blown mind-body response. The stress response is a reaction to an external threat, for example a fire alarm going off. In contrast, the willpower response is a reaction to an internal conflict. You want to do one thing, such as smoke a cigarette or supersize your lunch, but know you shouldn’t. Or you know you should do something, like file your taxes or go to the gym, but you’d rather do nothing.

The need for self-control sets into motion a coordinated set of changes in the brain and body that help you resist temptation and override self-destructive urges. It’s called the pause-and-plan response and it puts your body into a calmer state, unlike the adrenaline rush of stress. It also sends extra energy to the brain’s prefrontal cortex, which keeps track of your goals and helps you override impulses and cravings. The result is you have the mindset and motivation to do what matters most.

How can sleep, stress, and nutrition affect our ability to resist temptations and accomplish what we really want, or need, to do?

The biology of stress and the biology of willpower are simply incompatible. So any time we’re under chronic stress it’s harder to find our willpower. The fight-or-flight response floods the body with energy to act instinctively and steals it from the areas of the brain needed for wise decision-making. Stress also encourages you to focus on immediate, short-term goals and outcomes, but self-control requires keeping the big picture in mind. Learning how to better manage your stress – or even just remembering to take a few deep breaths when you’re feeling overwhelmed or tempted — is one of the most important things you can do to improve your willpower.

Sleep deprivation (even just getting less than six hours a night) is a kind of chronic stress that impairs how the body and brain use energy. The prefrontal cortex is especially hard hit and it loses control over the regions of the brain that create cravings and the stress response. Unchecked, the brain overreacts to ordinary, everyday stress and temptations. Studies show that the effects of sleep deprivation on your brain are equivalent to being a little bit drunk! The good news is any step toward more or better quality rest can be a real boost to self-control. When the sleep-deprived catch a better night’s sleep, their brain scans no longer show signs of prefrontal cortex impairment.

Nutrition comes into play because it also influences how available energy is for the brain. Something as simple as eating a more plant-based, less-processed diet makes energy more available to brain and can improve every aspect of willpower from overcoming procrastination to sticking to a New Year’s resolution.

Is willpower a limited resource?

Yes, and no. One of the most replicated findings in the field of willpower research is that people who use willpower seem to run out of it. Interestingly, any act of self-control leaves people with less willpower for completely unrelated challenges. Trying to control your temper, ignore distractions or refuse seconds all tap the same source of strength. The research also shows that willpower decreases over the course of the day, as your energy gets “spent” on stress and self-control. This has become known as “the muscle model” of willpower. Like your biceps or quadriceps the willpower “muscle” can get exhausted from effort.

But that doesn’t mean we’re all doomed to run out of willpower by noon. I prefer to talk about becoming a willpower athlete. Any muscle in your body can be made stronger through exercise. If willpower is a muscle, even a metaphorical muscle, it should be possible to train it. That’s what the research shows. As with physical exercise, using your self-control muscle may be tiring, but over time the workout increases your strength and stamina. So what starts out difficult becomes easier over time. New behaviors become habits, temptations become less overwhelming and willpower challenges can even become fun.

How can the brain be trained for greater willpower?

Two things have been shown to train the brain’s willpower reserve, or strength: meditation and physical exercise.

Meditation training improves a wide range of willpower skills, including attention, focus, stress management, impulse control and self-awareness. It changes both the function and structure of the brain to support self-control. For example, regular meditators have more gray matter in the prefrontal cortex. And it doesn’t take a lifetime of practice — brain changes have been observed after eight weeks of brief daily meditation training.

Physical exercise also leads to similar changes in the brain, especially the prefrontal cortex; however it’s not clear why. Regular exercise – both intense cardiovascular trainings and mindful exercise like yoga — also makes the body and brain more resilient to stress, which is a great boost to willpower.

As the clock counts down on 2011, many of us will resolve to break bad habits or accomplish personal goals in the New Year. Previous research has suggested that trying to tackle more than one resolution at a time is too taxing for the brain and the wrong strategy for making behavioral changes.  What’s an example of a more effective approach?

The best way to make a resolution is to think big and think small. People fail when they rattle off a whole list of changes they want to make without getting clear about what matters most to them.

You’re better off picking something you really want such as improving your physical health or saving for a down payment for your first home. Research shows that when you scale up to the big want, the biggest why, you automatically have more willpower. You’ll look for opportunities to make progress on your goal and be more likely to see how small choices can help you realize your goal.

The “think small” part is giving yourself permission to take microsteps toward your goal. Sometimes we get frustrated when we don’t know exactly how we’ll reach our goals. We can’t imagine how what we’re doing now will ever get us where we want. Or we try to take huge steps all at once and end up exhausted and overwhelmed. Choose small steps you can take that are consistent with that goal. When those steps are easy, or have become a habit, look for next steps and keep going.

Previously: How your perceptions about willpower can affect behavior, goal achievement, Stress, will-power top reasons why Americans fail to adopt healthy habits and Helping make New Year’s resolutions stick
Photo by Alisha Vargas

5 Responses to “ The science of willpower ”

  1. Ersan - Says:

    “Two things have been shown to train the brainÂ’s willpower reserve, or strength: meditation and physical exercise.”

    I agree, and posit an amendment:

    The third way to build your willpower muscle is to practice doing what you choose, exactly when you choose, regardless of how you feel at that moment.

    Start small. Don’t try to quit smoking at this point, because it probably won’t work til you build the willpower “muscle.”

    Humans seem opposed to the idea of a willpower muscle that requires training. We expect to quit smoking NOW, training be damned, and we beat ourselves up when we fail tomorrow.

    …But the choice won’t be effective if your willpower muscle is weak.

    …Which is likely is, if all you’ve racked up is a string of failures at quitting smoking.

    So, what can you do to build up that muscle?

    Like I said, start small with your choices.

    The next time you’re sitting on a couch and you’re thirsty, and you catch yourself thinking, “I’ll wait until commercial break”…. DON’T WAIT. Do it right then, specifically because you chose to.

    The less you “feel” like doing it, the better for your willpower-building cause because you’ll get better at doing whether you “feel” like it or not.

    As the days go on, you’ll find yourself taking on bigger opportunities to build that willpower muscles. And you’ll find yourself being successful at them.

    Keep building the muscle, and one day soon you won’t be daunted at all by quitting smoking.

    When to train? Look specifically for times when you’re feeling unmotivated, or like a failure. Snap out of it and remember this comment I posted.

    That’s when you should train.

    Don’t think; do.

    Remember to start small.

    You wouldn’t believe how fast we can build this new muscle… and how wonderful it feels when you can make a choice and know you’ll see it through.

    We’re so used to making ourselves wrong for failure that we finally learn to be effective it’s a blessed relief, like a dream come true….

    I speak from experience–although I, too, am still in training. 😉

  2. Health Information Says:

    I think meditation is a fantastic tool for calming and focussing the mind. With a calm mind, we can be far more rational about our decisions.

  3. Mike Dammann Says:

    You forgot life experience and properly analyzing it. Those who analyze properly are likelier to listen to their inner voice and will need less power to overcome what they internally are aware of keeping them from achieving the success they want.

    Mike Dammann

  4. sam Says:

    Contrary to popular belief, willpower is not an innate trait

    I don’t completely believe this. We are our “will”. conscience beings innately have willpower. why else would we be able to go past our physical limitations for example. a mothers baby is trapped under a car. through willpower the mother lifts up the car to save her child. ordinarily she would not be able to do this but through her willpower she overrides her normal muscle capacity. willpower is innate but not in the sense of being born or not being born with it. its innate in the sense of being within every conscience being. willpower seems to be a response to a need, but a response which we are all capable of.

    would anyone like to discuss this with me?

  5. CB Mishra Says:

    In my view, the phenomenon of will-power is inherent by nature. Because, the effectiveness of one’s response to own idea/choice or other’s advise about doing meditation for developing will power, may be sometimes governed or dependent on the impulses of co-related innate characteristics. It is a trait intricately linked with many others associated with the cognitive functions of brain/mind. Secondly, meditation can only help to stabilize, strengthen and polish one’s own existing inner characteristics. Meditation cannot acquire it from outside world or create within. Spiritually speaking, every individual body is pre-programmed with a default setting, even in activating the enormous back-up source graced to each one of us for support at the time of need!


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