What does it take to have the best memory in the United States? Only four and a half years of training, for five hours each day, according to three-time national memory champ Nelson Dellis.

Dellis just won the 2014 USA Memory Championship on March 29 in New York City, where he bested his own national record by recalling 310 digits in five minutes. He also set a new record in the process by memorizing 193 names and faces in 15 minutes.

And yet Dellis doesn't claim to have a photographic memory, or any other unusual brain powers besides extreme perseverance. In fact, he says anyone can do what he does.

"The [training] techniques are very simple, very learnable," he tells Mashable. "The only thing I'm doing differently is that I'm training more."

He details his not-so-secret training regime on his blog: seven decks of cards memorized each day, as well as a sequence of 360 random words, 600 names, 1,500 digits and 100 lines of poetry. That's more than one million bits of data memorized each year, by his own calculations.

Dellis' techniques, which were chronicled in the documentary Ben Franklin Blowing Bubbles at a Sword: The Journey of a Mental Athlete, also include associating numbers and cards with an action, person or object. He cobbles those images together as needed, which creates a distinct mental picture that facilitates memory.

Image: Wikimedia Commons

A former software developer, Dellis was inspired to train his mind when doctors diagnosed his grandmother, Josephine, with Alzheimer's disease.

"I have this memory of sitting at a table having dinner with her, my grandfather and me. And she said, 'When is Nelson coming here?'" Dellis told CNN in 2012. "I was sitting right in front of her... It never hit me like that."

Dellis began researching mnemonic techniques online soon after, and eventually competed in the 2009 USA Memory Championships. He failed to place in the contest, however, so he refocused his energies on another passion — mountain climbing. When his grandmother passed away later that year, Dellis decided to renew his efforts in memory training, and intertwine the two interests.

Never one to do things halfway — "I get very obsessive with things that I'm working on," he says — mountain climbing would become a major part of his mission to honor his grandmother's memory.

He won his first Memory Championship in 2011, and repeated the victory the next year, when he also ranked seventh in the World Memory Championships. In the process, he broke two national records by memorizing a full deck of shuffled cards in 63 seconds and 303 digits in just five minutes. His training regimen reportedly included memorizing a randomly shuffled deck of cards while climbing Mount Everest in 2011. (He was forced to turn back before reaching the summit due to problems with an oxygen mask.)

In 2012, Dellis founded Climb for Memory, a non-profit that raises funds for Alzheimer's awareness and research through mountain climbs, hoping the platform could garner attention for the cause. In 2013, memory software developer Fusion-io sponsored Dellis' second try at climbing Everest, which ultimately failed due to aggressively inclement weather.

Image: USA Memory Championship

In 2015, Dellis will give Everest one final attempt. He'll also climb Nepal's Manaslu, the world's eighth-highest peak, later this year. In the meantime, he's trying his hand at starting a memory tournament of his own, dubbed the Extreme Memory Tournament, with a goal of making memory sport "a lot more engaging for the audience," he says.

Taking place at the end of this month in San Diego, the tournament will feature a series of rapid-fire memorization events designed to "break down every event into short, exciting, head-to-head memory battles." Dellis has enlisted 16 of the world's best memory champions to compete, including the world's current top three mnemonists: Germany's Johannes Mallow and Simon Reinhard, and Sweden's Jonas von Essen.

Mental activities such as Dellis' techniques can help fight off the effects of Alzheimer's, so even a little of his secret sauce goes a long way.

"My thinking is, when I'm older and starting to get a little weaker in my mind, knowing I have these memory techniques will help sharpen my mind and stave that off a little bit," he says.

But he isn't too worried about someone using his mnemonic roadmap to swoop in and claim his throne. "I'm pretty confident that most people won't train that hard," he says. "[But] I guess there will be someone eventually."

If you're planning to give Dellis a run for his money, the graphic below will show you exactly how to do it.

Have something to add to this story? Share it in the comments.