It gets stronger with practice, weaker without it, and never simply runs out.
Willpower acts like a muscle in one important way: it gets stronger with practice and weaker when you stop using it. It does not act like a muscle in another way. The old idea that it “runs out” after one hard choice has largely failed to hold up in newer research.
So the better picture is a skill that needs daily upkeep. Here’s what the science says, what David Goggins and Andrew Huberman shared about it on the Huberman Lab podcast, and how to keep your will strong for years.
Where did the idea that willpower is a muscle come from?
The idea came from a famous 1998 study where people who resisted cookies gave up sooner on a puzzle afterward. Psychologist Roy Baumeister and his team called this “ego depletion.” They said willpower was like a tank of fuel that ran low with use.
For years, this was one of the best-known ideas in psychology. It showed up in books, talks, and countless articles. It also made intuitive sense. We all know the feeling of being “too tired” to make good choices at the end of a long day.
The theory had 2 parts. First, willpower gets used up in the short term. Second, it can be trained to grow over time, like a muscle at the gym. Science has since treated those 2 parts very differently.
Does willpower really run out?
The “running out” part is now in serious doubt, because a large 2016 test across 23 labs found almost no effect. That doesn’t mean you never feel tired. It means the simple fuel-tank model doesn’t hold up well.
In that project, published in Perspectives on Psychological Science, Martin Hagger and dozens of scientists repeated a standard ego depletion test with 2,141 people. The measured effect was close to zero.
There’s another twist, and an honest caution. In a 2010 study, Veronika Job, Carol Dweck, and Gregory Walton found that only people who believed willpower was limited showed the drop. But a careful 2023 repeat of that study with 187 people found neither the drop nor the belief effect. So the belief idea is hopeful, but unproven.
Takeaway: the evidence that willpower “runs out” is weak. Telling yourself “I’ve used up my willpower today” is a story you don’t have to believe.
Why does willpower fade when you stop practicing?
Willpower fades for the same reason other brain skills fade: the brain keeps what you use and trims back what you don’t. Scientists call this plasticity, and it runs in both directions.
A classic example comes from a 2004 study in Nature. Bogdan Draganski’s team taught people to juggle for 3 months. Brain scans showed growth in areas that track motion. Then the people stopped juggling for 3 months. On the next scan, much of that growth had faded.
Huberman made the same point about willpower and the anterior midcingulate cortex. He said this area can grow, but “just as easily” it can shrink, like Silly Putty. He shared a line from a friend who has been sober for 30 years: there’s a cure for addiction, but it only works one day at a time.
Goggins called his own willpower “a very, very perishable skill.” He said the moment he stops, he’d slide back toward the man he used to be.
How is willpower like a muscle, and how is it different?
Willpower matches a muscle in how it grows and fades with use, but it differs because it’s shaped by beliefs and doesn’t simply run dry. This table puts the comparison side by side.
| Question | A real muscle | Willpower |
|---|---|---|
| Grows with practice? | Yes, with steady training | Yes, especially with effort you’d rather avoid |
| Fades if unused? | Yes, within weeks | Likely, as brain changes fade without use |
| Runs out after heavy use? | Yes, it tires in minutes | Weak evidence, since a large replication found little effect |
| Affected by beliefs? | Only a little | Maybe. Early studies said yes, a 2023 repeat did not |
| Needs rest? | Yes, to rebuild | Sleep and recovery help, but daily practice matters most |
The helpful message here is balance. Train it like a muscle. Talk to it like a skill you own.
How do you keep willpower strong for life?
You keep willpower strong by practicing a little every day, raising the challenge as things get easy, and dropping the belief that it runs out. Here’s a simple maintenance plan.
- Do 1 unwanted task daily. Even 5 minutes. The habit matters more than the size. Our guide on how to build willpower has a full list of ideas.
- Change your self-talk. Swap “I’m out of willpower” for “I’ve got more in me than I think.” Since the fuel-tank idea is weak, there’s no reason to talk yourself out of trying.
- Keep a hard thing in your week. Goggins spends months each year as a wildland firefighter, work he says keeps him from getting soft. You don’t need that. A hard hike or a tough class can do the same job.
- Protect your sleep. Tiredness makes every choice feel heavier. Rest is part of discipline, too.
- Expect about 2 months for a habit to settle. A 2010 study by Phillippa Lally found new habits took a median of 66 days to become automatic, with a wide range from 18 to 254 days.
What if you’ve lost your willpower after a long break?
Start again smaller than you think you need to. The juggling study also showed that people kept some of their gains even after stopping. You’re not starting from zero, and your brain remembers more than you fear.
Frequently asked questions
Is willpower a limited resource?
Probably not in the simple way people once thought. A 2016 test across 23 labs with more than 2,000 people found almost no ego depletion effect.
Can you lose willpower?
Yes, willpower seems to fade when you stop practicing it. Brain changes from training tend to shrink without use, which is why daily practice matters.
How do you strengthen willpower like a muscle?
Do small tasks you don’t want to do, every day, and make them harder as they get easy. Pair this with good sleep and kind, confident self-talk.
What is ego depletion?
Ego depletion is the idea that self-control uses up a limited mental resource, so resisting one temptation makes the next one harder. Large recent studies have not found strong support for it.
Why do I have no willpower at night?
Tiredness, stress, and a long day of decisions all make night choices feel harder. Plan tempting moments ahead and make the easy choice the healthy one.
Think of your will as a flame you tend each day. The universe keeps sending you signs. Get one in your inbox every morning → For the bigger picture of how small daily actions shape your future, read our guide to manifesting.