• Stretch
  • Posts
  • The Willpower Instinct: The Power of I will - I won't - I want

The Willpower Instinct: The Power of I will - I won't - I want

🤸‍♀️ Stretch 49

Alright, let’s try something new for a few weeks.

I’ll be sharing notes from a book called The Willpower Instinct by Kelly McGonigal. Each chapter covers a key scientific insight + practical exercises/strategies to develop self-awareness and work on whatever you struggle to consistently say YES or NO to.

What got me interested is how McGonigal describes willpower as a biological function that we can improve through mindfulness, exercise, nutrition, and sleep.

As I always say, we have so much more control than we think! It’s simply about having a basic understanding of how our brains and bodies work.

McGonigal encourages to approach the ideas in the book like a scientist, and to pick a specific “willpower challenge” to experiment with. Right up my alley 👩‍🔬 

I’ll read one chapter every week and share highlights here.

(Don’t ya worry, I’m also doing a BreathWorkHold course with Erwan Le Corre so there’ll be plenty of breathwork stuff too 😍.) 


  • Pick a Willpower Challenge: The best way to learn is to do.

  • Week 1 of The Willpower Instinct: The powers of I will - I won’t - I want.

  • The Ego Depletion theory. Is willpower a limited or unlimited resource? Is it like a muscle? Or is it all in your head?


Before we jump into the book, wouldn’t it be fun if we all picked a willpower challenge?

And then every week, you’ll read the notes through the lens of your challenge and become a mean lean willpower machine. Wouldn’t that be so-much-FUN? 🤗

When you’re done reading this email, hit reply and let me know if you’re in and what your willpower challenge is. This can be any habit you want to start or quit, in any area of your life where you want to be more disciplined and achieve long-term goals.

Here’s the one I set for myself for the next 10 weeks:

  • 3 runs per week

  • stretching and mobility on the non-running-days using Pliability app

  • always run without podcasts or music

I wrote down a few reasons why I want this (You’ll find out later why that’s important):

  • I want to feel strong, lean and healthy.

  • I want the emotional and mental benefits that come from daily exercise and movement. Endorphins / endocannabinoids / dopamine / serotonin release, improved sleep, improved focus, etc. If the benefits of exercise could be packaged in a pill, it’d be the single most widely prescribed pill in the world!

  • I want the mental resilience training that comes from going for long runs every week, no matter what else is going on in my life. No negotiation, no excuses.

  • I want the creative benefits—giving my brain a rest after long days spent on the computer, allowing my mind to wander and come up with ideas and solutions. (The combination of increased blood flow to the brain and the meditative state of running improves creativity and problem-solving skills.)

  • I want the mental clarity that comes from going for runs without any input and stimulation. Simply hearing my own thoughts.

  • I want the social benefits that can come from running—running with friends, going to running events. Creating friendships around the activity of running.

I could’ve just written “I want to run more because I’m training for a half marathon in October.”

It’s correct, but it’s too vague. I’d crumble at the first sign of resistance.

Being so detailed and so clear about why I want to be disciplined around running regularly without any external stimulation makes it much easier to get out and leave the earbuds at home—so far, at least!

Alright, let’s get to the first chapter of the book.


Willpower—the ability to control your attention, emotions and desires. The ability to make conscious choices instead of letting your life be dictated by impulses and short-term thinking.

🦍 Why and how we developed willpower

The answer to “why" is simple:


The need to fit in, cooperate, and maintain long-term relationships put pressure on our early human brains to develop strategies for self-control.

Think of willpower as evolution's way of ensuring we didn't eat all our berries in one go, or we'd have to explain to Grog why there's none left for him…

The “how” answer is fascinating.

As Kelly describes in detail in the book, the answer appears to be the development of the prefrontal cortex (PFC)that bit of your brain just behind your forehead.

For most of evolutionary history, the PFC was like a basic car engine, mainly there to control physical movement.

As humans evolved, the PFC got bigger and better connected to other areas of the brain.

You can now think of it like the dashboard of a fancy car, managing higher-order functions like decision-making, planning and organising, problem solving as well as impulse control.

Now, McGonigal highlights that willpower isn’t just one cog in the brain machine.

The PFC can be divided into 3 key regions that are responsible for willpower.

  • “I will” power: The ability to do something you don’t necessarily want to do—controlled by the region near the upper left side of the prefrontal cortex. This power helps you start and stick to boring, difficult or stressful tasks (like staying on the treadmill when you’d rather hit the shower.)

  • “I won’t” power: The ability to not do something you want to do—controlled by the region near the right side of the prefrontal cortex. This power holds you back from following every impulse or craving (like resisting to grab your phone while you’re driving.)

  • “I want” power: The ability to keep in mind your long-term goals—controlled by the region just a bit lower and in the middle of the prefrontal cortex. To say no when you need to say no and to say yes when you need to say yes, you need the ability to remember what you really want.

🧠 Hey, Brain…
When you’re wrestling with being disciplined around your willpower challenge, ask yourself: what makes it so hard? Write down what comes up.

Then, write down some bullet points for “I will” - “I won’t” - “I want” related to your willpower challenge.

What will you do? What won’t you do? Why do you want this?

🤯 The problem of two minds

So, we all have a prefrontal cortex that is designed to help us resist temptation and prioritise our long-term goals.

Then… why is it so damn hard to do?!

And why does it feel like we’re in a constant debate with ourselves?

(“Just go for that run tomorrow. No I should really do it today. Why though? What’s the big deal? It’s dark already. You’re tired, it’s okay.”)

Neurologically, experientially, you are both of those voices. One voices comes from one part of the brain, the other voice comes from another.

Kelly shares another fascinating evolution tidbit to explain this:

Nature prefers to add on to what it’s created, rather than start from scratch. So as humans required new skills, our primitive brain was not replaced with some completely new model—the system of self-control (PFC) was simply built on top of the old system of urges and instincts.

And that’s how you get that internal friction:

It’s your prefrontal cortex versus the more primitive parts of your brain.

Self-control, long-term thinking and decision-making versus desire, impulse and immediate gratification.

Now, it’s not as simple as saying one is good and the other is bad. Without desires, we become depressed. Without fears, we’d fail to protect ourselves from future danger.

It’s simply about being aware of what’s going on in your brain and being able to navigate this balance.

By understanding your impulses and recognising when you want to exercise self-control, you can activate your PFC and make conscious choices instead of defaulting to the easiest option.

🧠 Hey, Brain…
What is the short-term gratification voice saying? What is the long-term thinker saying? Write it down.

Can you link the answers back to what you WANT? This will help you manage that primitive, short-term thinking voice.

🧘‍♀️ Training your brain for willpower

Neuroplasticity is now one of the most widely accepted findings in neuroscience:

Your brain is not fixed. Your brain is remarkably responsive to experience, which means it can get better at things.

And there is growing scientific evidence that you can train your brain to get better at self-control.

One of the best ways to do that is through… meditation.

Neuroscientists have discovered that when you ask the brain to meditate, it gets better not just at meditating, but at a wide range of self-control skills, including attention, focus, stress management, impulse control, and self-awareness.

People who meditate regularly aren’t just better at these things.There are actual physical, structural changes happening to their brain. Increased neural connections between regions of the brain important for staying focused, ignoring distractions and controlling impulses. More gray matter in the prefrontal cortex, as well as regions of the brain that support self-awareness.

In the book, Kelly prescribes a simple breath meditation. (I talk more about why and how to do that here.)

 🧠 Hey, Brain…
Let’s give this breath meditation a try.

If you’ve tried meditation before and you felt like you couldn’t do it because your mind kept wandering, I have good news for you: that’s the best training!

What you’re training in meditation is exactly what you need to do in real life: catch yourself moving away from a goal and then point yourself back at the goal (in this case, focusing on the breath). So being “bad” at meditation is exactly what makes the practice effective.

»»» NEXT WEEK: CHAPTER 2: the biology of willpower, including the role of the PCF and how certain changes in the brain can affect our capacity for self-control.


When discussing willpower, it’s important to briefly talk about some of the “science controversies” in recent years.

For the longest time, there was an accepted theory of ego depletion—the idea that willpower is connected to a limited reserve of mental energy. Once we run out of that energy, we’re more likely to lose self-control.

But recent studies challenge this theory.

In a study conducted by the Stanford psychologist Carol Dweck (famous for her Growth Mindset theory), Dweck concluded that signs of ego depletion were observed only in test subjects who believed willpower was a limited resource. Those participants who did not see willpower as finite did not show signs of ego depletion.

If these findings hold, that’s a pretty significant.

In Dweck’s theory, lack of self-control is essentially caused by self-defeating thoughts. By believing you’re too tired or too busy to prioritise long-term goals over short-term gratification.

Like the Henry Ford quote: “Whether you think you can, or you think you can't…you're right.”

So anyway, this is a good reminder to view all of these popular science theories with a critical mindset.

It’s not about blindly believing or sticking with a particular theory. Whether willpower is a limited or unlimited resource doesn’t really matter. I’ll keep both theories in mind as I’m reading the book. For me, it’s more about being curious about what’s going on in my brain as I’m struggling with willpower, having a basic understanding of the biological and neurological processes, experimenting, observing what works for me and what doesn’t, and then… pick myself up and go for that run! 🏃‍♀️w

Join the conversation

or to participate.