Professional athletes fuel their bodies for peak performance. They carefully calibrate every calorie they consume. In much the same way,  successful entrepreneurs and leaders are intentional about the fuel they feed their minds.  

It's not easy to control what you think about because internal and external forces are at work to steal your attention. We're learning a lot more about the extent that social media algorithms are designed to keep you hooked. Unfortunately, they do so by stoking anger and negativity--not exactly the mindset that'll keep you in a positive, optimistic frame of mind.  

The algorithms are simply taking advantage of our brain's internal wiring. A seminal paper in behavioral economics titled "Bad Is Stronger Than Good" revealed that the "negativity bias" is a near-universal tendency to respond more strongly to bad news than good. Focusing on the bad, in turn, affects our emotional well-being and saps us of the energy we need to turn our ideas into reality.

Over two decades of working with the world's most successful CEOs and entrepreneurs, I've learned that they, too, are susceptible to being dragged down by a steady stream of bad news. What makes them different is they've learned to optimize their brain for success by paying attention to what they put in it. Here's a few ways you can do this.

1. Keep biographies on your nightstand.

Leaders are readers. Specifically, they read more biographies than average. I recently met with a CEO of a giant pharmaceutical company who told me he devours every book on his hero, Abraham Lincoln. He asks himself, "What would good Abe have done in this situation?"

Since books that are out of sight are out of mind, I buy biographies in hardcover and keep them on my nightstand as reminders to spend more time diving into a remarkable person's life.

This week I'm reading two biographies of remarkable leaders: James Dyson and Indra Nooyi. From Dyson, I'm learning how to turn perceived failures into progress. From Nooyi, I'm learning the skills required to stand out in a competitive global environment.

Spend time in the presence of remarkable people.  

2. Read progress books.

Over the last few years I've been reading "progress books." These are books written by thinkers, scholars, and scientists who use data to show that the world is getting better every day. Billionaires like Warren Buffett and Bill Gates are fans of the category. They read and recommend books such as Steven Pinker's Enlightenment Now, Matt Ridley's The Rational Optimist, and Hans Rosling's Factfulness.

Reading these books will change the way you look at the world. Instead of roadblocks, you'll start seeing opportunities at every turn.

3. Keep a gratitude journal.

I'll admit that when I first heard of gratitude journals, I thought they were a little silly. Then I became friends with a CEO who started with nothing and now runs one of America's largest real estate companies.

After one lunch together, he told me that he'd write about our meeting later in his journal.

"Your journal?" I asked.

"Oh, yes. I never end the day without writing down three things that happened that I'm grateful for," he said. "When I wake up, I look at the entries again, and meditate before I turn on the television or read the news."

This CEO is intentional about what he feeds his mind at the end of the day and first thing in the morning. It's no coincidence that he's a bundle of energy throughout the day and nearly always has a smile on his face.

Energy is a precious resource, and your brain hogs a lot of it. Keep your mind sharp and focused by feeding it the right fuel.