Mental grayness. Hazy thoughts. Unmotivated sluggishness.

We all know what it's like to feel down. When we wake up and still feel tired, when the afternoon lull hits us at our desk, when we get home from work grumpy.

It's a natural part of life to feel uninspired. It happens to everyone.

But what about world icons, billionaires, and successful business leaders? What do they do when they aren't on the top of their game?

Turns out, for those who can't afford to take a "time out," they have a quiver of tricks and habits from they pull to reactivate their positive drive.

Take a shower.

When digital entrepreneur Kevin Rose asked him where his ideas come from, Tesla and SpaceX founder Elon Musk said he read every comic book in the store growing up. Iron Man, Batman, Green Lantern - all of them - helped foster a supernatural imagination in the young inventor.

Today, Musk attributes the conception of his best ideas to the morning shower. "What's really happening is stuff has percolated in the subconscious and it's not really occurring in the shower but you're getting the results of last night's computations."

Immerse yourself in a sensational experience.

Musk remembers a particular lightbulb moment in which he got the idea for a "supersonic vertical takeoff landing electric plane" at Burning Man, an annual gathering that takes place in a temporary city erected in the Black Rock Desert in Nevada. In short, Burning Man is a sacred Petri dish of raw human creativity and Babylonian experimentation. It's where Silicon Valley sheds all traces of professionalism and wraps itself in unencumbered self-expression. Musk has touted the festival as a "very creative place."

Similar to Musk, American actor and singer Neil Patrick Harris was asked how he gets unstuck from a creative rut. He responded, "I go see something viscerally inspiring. Something immersive where you have to go to a place and really feel the air and the smells."

Drink a glass of water.

For others, you don't have to take such dramatic action. One of my favorites and perhaps the simplest habit is from Vox.com founder and editor-in-chief Ezra Klein who told Thrive Global his secret life hack.

"Irritated and not sure why? Drink water."

A study published in the Journal of Nutrition conducted by the University of Connecticut confirms Klein's tip: even mild dehydration can alter your mood.

Schedule blocks of free time during the day.

LinkedIn CEO Jeff Weiner prevents burnout and self-recharges by scheduling 30-90 minute chunks of free time in his daily schedule. He purposely and systematically adds these buffers of nothing. "The buffer is the best investment you can make in yourself and the single most important productivity tool I use," he said in a LinkedIn post.

Meditate.

Meditation is not as unusual and as unattainable of an action as we may think. Twitter and Square dual CEO Jack Dorsey and celebrity TV host Ellen Degeneres turn to meditation techniques to re-up on their inspiration when it bottoms out.

The mental modes practiced by these ultra-achievers fall into two categories: wabi-sabi and Transcendental Meditation.

For Jack Dorsey, who meditates for 30 minutes every morning, subscribing to Wabi-Sabi is not just a world view but a design philosophy that shows up in his products. An ancient Japanese concept, Wabi-Sabi states that there is beauty in imperfection and impermanence.

With a belief that things don't have to be perfect to be right, it's no wonder Dorsey can keep his cool despite the chaos of leading two publicly traded tech firms.

For Ellen Degeneres, and other big names like Oprah Winfrey and entrepreneur Russell Simmons, Transcendental Meditation (or TM) provides the grounding needed for reaching one's full potential.

This technique requires the meditator to sit for at least 20 minutes each day, focusing entirely on a secret personal mantra. TM mantras tend to be a single word received from a qualified TM teacher. Examples of mantras include "Aim" or "Ayinga" or "Shirim."

Neither a religion nor philosophy, TM is practiced by many of Hollywood's elite, including Jerry Seinfeld, Paul McCartney and Hugh Jackman who all credit the practice for giving them peace and calmness. For Ellen, TM has become essential. She said at the opening of the David Lynch Foundation 3rd annual Change Begins Within Gala that other meditations didn't work for her and TM is the only time where she can feel still and peaceful.

Get around people.

Virgin billionaire Richard Branson said he feels more inspired by people's potential than by business proposals with great ideas.

He wrote on LinkedIn, "I get a lot of business proposals and they are usually fascinating to hear, as you never know where the next game-changing idea will come from. Yet it is the personal tales of people I meet that are most inspiring. ... Often I am more struck by the potential of an individual than their idea."

On the other hand, inspiration can be replenished by the written ideas of a specific author.

Pick up a book.

Craigslist CEO Craig Newmark reads the work of Canadian singer and poet Leonard Cohen.

"... there's this guy, Leonard Cohen, who's been a real influential poet and singer for maybe fifty years. He's my rabbi, in the sense that a rabbi's a teacher and spiritual leader," said Newmark.

"His music is pretty much my liturgy, prayer really," wrote Newmark. "And it inspires me in a way to get through the day,"

On a less pious note than Newmark, Facebook founder and CEO Mark Zuckerberg relies on an intellectual curiosity to fill the empty coffers of his inspiration. An outspoken and voracious reader, much like other billionaires Bill Gates and Warren Buffett, Zuckerberg told The New Yorker his favorite book is not Ender's Game and added that he enjoyed reading the Aenid more.

Zuckerberg is known for his "Year of Books" resolution in which he sought to establish a habit of reading one book every other week. One Quora reader hypothesizes that to do this, Zuckerberg reads for 30 minutes every day.

Sweat.

Finally, exercise is the needed mental reset button for other power players.

Irene Rosenfield, CEO of Mondelez International, the mother company of household brands like Kraft, Oreos, and many others, and a Top 10 Most Powerful Woman according to Fortune, is known for being fiercely competitive on the tennis court and passionate about rollerblading.

"Endorphins are a very powerful thing," Rosenfield told Forbes in an interview. "Sports have always been a really important part of how I energize myself, as well as how I relax. I spend a lot of my spare time with my family playing tennis, biking, and Rollerblading."

Do something about it.

Next time you're staring blankly at the ceiling, treading in the murky waters of frustrating unimagination, remember what these productivity titans do to regain their drive.

Whether it's exercise, meditation, people, or even a simple swig of water, there's no reason to stay stuck. The worst thing you can do is nothing. Unless you're Jeff Weiner and it's intentional.

The point is that we can learn from some of the world's most successful people to adopt a habit (it doesn't have to be one from this list) to lift our creativity when we feel uninspired.

Published on: Mar 23, 2017