Ever feel like you just wanna give up on something? How can you develop the inner strength necessary to achieve your long-term goals?

Turns out that grit — the perseverance that keeps us going — is a lot more important than you might think. In fact, it's the best predictor of success among West Point cadets.

From Drive: The Surprising Truth About What Motivates Us:

The best predictor of success, the researchers found, was the prospective cadets' ratings on a noncognitive, nonphysical trait known as "grit" — defined as "perseverance and passion for long-term goals."

Stanford researcher Catharine Cox studied 301 eminent historical figures. What conclusion did she come to? Persistence beats smarts.

From Grit: The Power of Passion and Perseverance:

"...high but not the highest intelligence, combined with the greatest degree of persistence, will achieve greater eminence than the highest degree of intelligence with somewhat less persistence."

So we all need more grit. But how do we get there? I decided to call an expert.

In 2013, Angela Duckworth was awarded the MacArthur "Genius" Award for her work on grit.

She's a professor at the University of Pennsylvania and author of Grit: The Power of Passion and Perseverance. Here's her TED talk:

Duckworth and I talked about the four things that lead to the development of grit — as well as a fifth element that's a shortcut to the inner strength we all need to succeed.

Let's get to it.

1. Pursue what interests you

It's hard to stick with something over the long haul if you don't care. So the first step to grittiness is finding something that deeply interests you. Here's Duckworth:

The first period is interest development — where you fall in love with something. You find that you're thinking about it more and more.

So you need to sit back and ponder what you're passionate about, right? Wrong. Duckworth says introspection is not the right path. You need to get out there and try stuff so you really know what's perfect for you.

And once you think you've found something you're really excited about, Duckworth recommends picking a role model or teacher to help you along.

When I spoke to her UPenn colleague, professor Adam Grant, he said a mentor is key to turning passion into skill. Here's Grant:

...often interest precedes the development of talent. It's having a coach or teacher who really makes something exciting to be involved in that leads you to put in the practice necessary to become an expert at it.

(To learn a Navy SEAL platoon commander's secrets to grit, click here.)

Alright, so you know what you want to be gritty at. What's the next step?

2. Practice, practice, practice

Hard work develops skill, and we're more likely to stick with things we're good at. Here's Duckworth:

Second, you develop a capacity for doing hard practice — the kind scientists call "deliberate practice." Over years of working in a very diligent way on your weaknesses, you improve.

Like she said, working on weaknesses is key. And she's not the only grit expert who believes this. When I spoke to former Navy SEAL James Waters, he said this is exactly what makes SEALs so tough.

They do a debrief after each mission to review what happened and spend 90 percent of it discussing what they could do better next time. Here's Waters:

When you go out on a mission, you always acknowledge your successes but much more important than that is you take a hard look at your failures and are willing to accept criticism. One of the key strengths of the SEAL Teams is the culture of constant self-improvement. No one ever says, "That's good enough." On almost every real world mission I was on — even the most successful ones — we spent 90 percent of our post-mission debrief focusing on what we did wrong or could have done better.

When I spoke to Anders Ericsson, who did the original "10,000 hours" research, he emphasized that deliberate practice isn't easy. It's intense. (To learn how to do deliberate practice the right way, click here.)

So how do you muster the grit to do that hard work before you're truly gritty? Duckworth says, "Change the way you experience it."

And, once again, the Navy SEALs agree. Waters said the secret to getting through the near-impossible SEAL training (BUD/S) was to turn it into a game. Here's Waters:

Many people don't recognize that what they're doing at BUD/S is assessing your ability to handle a difficult circumstance and keep going. It's a game. If you want to be a Navy SEAL, you've got to play that game. You've got to have fun with it and you've got to keep your eye on the bigger picture.

(To learn the scientific way to become an expert at anything, click here.)

Okay, you're passionate and working hard. But plenty of people can say that. What do the truly gritty people do that leaves everyone else behind?

3. Find purpose

The difference between someone who is just a hard worker and somebody who has real grit is that the latter finds meaning in what they do. And that meaning involves serving others. Here's Duckworth:

Third is purpose. Having a sense of the greater meaning of your work. How it's important to other people, not just interesting to you.

Studying 16,000 people, Duckworth found that "grittier people are dramatically more motivated than others to seek a meaningful, other-centered life."

From Grit: The Power of Passion and Perseverance:

What ripens passion is the conviction that your work matters. For most people, interest without purpose is nearly impossible to sustain for a lifetime. It is therefore imperative that you identify your work as both personally interesting and, at the same time, integrally connected to the well-being of others.

Gritty people don't merely have a "job." They have a calling in life. She explains it with this story from Grit: The Power of Passion and Perseverance:

Three bricklayers are asked, "What are you doing?" The first says, "I am laying bricks." The second says, "I am building a church." The third says, "I am building the house of God." The first bricklayer has a job. The second has a career. The third has a calling.

And helping others through your work doesn't just make you gritty — it also makes you love what you do. People who perform work that benefits society show high levels of job satisfaction. And that leads to an upward spiral of grit.

From How to Find Fulfilling Work:

A major study of ethical work by Howard Gardner, Mihaly Csikszentmihalyi, and William Damon showed that those doing what they call 'good work' — defined as 'work of expert quality that benefits the broader society' — consistently exhibit high levels of job satisfaction.

I know what some of you are thinking: I want to be gritty at my job, but I don't find meaning in it.

No problemo. Think about what you do that helps others. This alone boosts grit. Beyond that, other research shows that tweaking how you see your job can make a huge difference.

From Grit: The Power of Passion and Perseverance:

David Yeager recommends reflecting on how the work you're already doing can make a positive contribution to society... reflecting on purpose led students to double the amount of time they spent studying for an upcoming exam, work harder on tedious math problems when given the option to watch entertaining videos instead, and, in math and science classes, bring home better report card grades. Amy Wrzesniewski recommends thinking about how, in small but meaningful ways, you can change your current work to enhance its connection to your core values.

(To learn how to develop the mental toughness of an Olympic athlete, click here.)

Passion, deliberate practice, and purpose. Great. But what's the final step that will turn you into a juggernaut of grit?

4. Have hope

Sound corny? No, this isn't just wishing things will go well. Duckworth says you need an active type of hope. You must believe things will improve because you're going to improve them.

From Grit: The Power of Passion and Perseverance:

One kind of hope is the expectation that tomorrow will be better than today. It's the kind of hope that has us yearning for sunnier weather, or a smoother path ahead. It comes without the burden of responsibility. The onus is on the universe to make things better. Grit depends on a different kind of hope. It rests on the expectation that our own efforts can improve our future. "I have a feeling tomorrow will be better" is different from "I resolve to make tomorrow better." The hope that gritty people have has nothing to do with luck and everything to do with getting up again.

Now hope may sound fuzzy and unscientific but it's not. Research shows people without hope avoid bigger challenges, quit earlier, and act helpless. What could be more anti-grit than that?

From Ungifted: Intelligence Redefined:

These results suggest that hope, as defined by Snyder and colleagues, is not just a feel-good emotion, but a dynamic cognitive motivational system… According to their theory, those lacking hope typically adopt performance goals and choose easy tasks that don't offer a challenge or opportunity for growth. When they fail, they quit. They act helpless and feel a lack of control over their environment.

So what should you do if you're not too hopeful? Two things: have a "growth mindset" and use "optimistic self-talk."

Duckworth says these two lead to perseverance over adversity. A growth mindset is the attitude that your abilities aren't fixed. Don't focus on innate talent. Believe you can get smarter and better at anything if you work hard.

And optimistic self-talk is as simple as telling yourself "I can do it" when things get difficult. In fact, the U.S. military has taught this to recruits in order to increase their grit.

(To learn how to develop a growth mindset, click here.)

So those are the big 4 ways you can develop grit. Yes, they can be really hard.

But is there another way that's easier? Or something you can use to complement the above strategies when you're at your limit? Yes.

5. Join a gritty group

Hang out with gritty people or join a gritty company and it will rub off on you. Here's Duckworth:

...Dan Chambliss said to me, "If you want to become a great swimmer, you should join a great team." I really didn't understand what he meant, but he unpacked that a little bit. He's said, "Look, I'm not a particularly industrious guy, but I'm hanging out with all these hardworking faculty, reading papers, writing papers, and I just fall in line with the rest of them because that's what people do, we conform." He said, "If you want to be gritty, hang out with gritty people."

We like to think we're all unique snowflakes but we're inevitably influenced by those around us. News flash: that doesn't have to be a bad thing. Peer pressure can be awesome if you use it the right way.

From Grit: The Power of Passion and Perseverance:

Over time and under the right circumstances, the norms and values of the group to which we belong become our own. We internalize them. We carry them with us. "The way we do things around here and why" eventually becomes "The way I do things and why."

When I spoke to Stanford GSB professor Bob Sutton, he told me his #1 piece of advice to students was this:

When you take a job take a long look at the people you're going to be working with — because the odds are you're going to become like them, they are not going to become like you.

(To learn how your friends can be the easy way to an awesome life, click here.)

We've learned a lot from Duckworth. Let's round it all up and find out the most surprising benefit of grit.

Sum Up

Here's what Duckworth says will build that inner strength and make you gritty:

Pursue what interests you : You're not going to stick it out if you don't care.

: You're not going to stick it out if you don't care. Practice, practice, practice : It's not just how you get to Carnegie Hall. We love doing things we're good at.

: It's not just how you get to Carnegie Hall. We love doing things we're good at. Find purpose : How does what you do help others? That's what makes a job into a calling.

: How does what you do help others? That's what makes a job into a calling. Have hope : No "wishing on a star" here, pal. Have hope because you are going to make it happen.

: No "wishing on a star" here, pal. Have hope because you are going to make it happen. Join a gritty group: Mom was right; spend time with slackers and you'll be a slacker.

So you do all of these things and become a Tyrannosaurus of grit. Awesome. Know what else you will be?

Happy.

Duckworth surveyed 2,000 people and the results were clear: "I found that the grittier a person is, the more likely they'll enjoy a healthy emotional life."

And it's not some lazy, starry-eyed contentment. Gritty people strive every day and enjoy new challenges. That's the exciting kind of happiness. Here's Duckworth:

I was talking to Brad Stevens who's the coach of the Boston Celtics. He said, "I'll never be the coach I want to be, but it sure is fun trying." It's not that gritty people are necessarily content in the comfortable sense, but they are content in the sense that they enjoy the pursuit of excellence and there's nothing they'd rather do than keep trying to get better everyday.

Everyone today is concerned with work-life balance. It's nice to know that the same quality that can make you a success in your career can help promote happiness at home.

You should never give up on being happy. Or better yet: never give up on yourself.

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