While you might not think of your brain in the same vein as, say, your heart or biceps, it's very much the same as a muscle in the sense of "use it or lose it". To make your brain function stronger and avoid cognitive decline, you've got to do some mental heavy lifting. And that means puzzles like crosswords and Sudoku, right?

Not quite, according to psychiatric epidemiologist Jessica Langbaum. In an interview airing on NPR, Langbaum, who serves as the associate director of the Alzheimer's Prevention Initiative at the Banner Alzheimer's Institute, that she doesn't play those types of standard games to stay mentally fit. Instead, she just goes to work.

Yeah. You didn't misread that. She just goes to work.

The rationale is simple. Games like Sudoku do benefit your brain, but they're too narrowly focused on one task most of the time. To really get your brain to break a sweat and improve its overall fitness, you have to get it using information from and processing in lots of different areas.

"While you're still in the workforce, you are getting that daily challenge of multitasking, of remembering things, of processing information," Langbaum asserts.

Langbaum still points out that research on cognitive decline has come a long way and that the brain training programs in use now are much more demanding than they used to be. And she says that it's still fine to do everyday puzzles and games, so long as you're switching up the activities and they're ones you actually like to do.

But her biggest recommendation is even easier.

Just spend time with people.

"People who have a lot of social interactions, particularly in mid-life, have a lower risk of Alzheimer's dementia in later life," she claims. "There's something about being around people that's helpful for our brains."

As a bonus, social interaction has been shown to benefit general physical health, too. So as you keep your mind pumped, you might see improvements in areas like blood pressure, immunity and energy.

So one big takeaway here is, as an entrepreneur or leader, don't fall into the trap of isolating yourself at your desk. Make sure there's time on your calendar for friends or family or even team building events, especially if you do a lot of remote work. Master the art of delegation as the demands of business get bigger, rather than turning down the chance to interact.

Secondly, don't make the mistake of thinking this is an area where more is always better. The brain needs challenges like complex projects at work, but it also isn't designed to run at full steam 24/7. You need to give it a chance to downshift through the day. Researchers now think that mentally resting every 90 minutes or so is ideal, so schedule your work tasks and meetings accordingly. Give yourself 20 minutes to close your eyes, take a catnap, stretch, chill out with some relaxing music or just grab a munchie. If you can't take those small breaks, that's a huge warning sign you're overscheduled or that operational policies need tweaking. Be more realistic about the work load you take, find someone who can assist you or create new protocols.

Now, all this said, some jobs do require more mental effort than others. If you're in a position where your job is truly, embarrassingly mundane or you've been at it so long you could do it sleepwalking, it might be time to ask for more or different responsibilities or even change careers altogether. At the very least, get out and volunteer, which will give your brain new jobs and the chance to be with others, all while increasing your visible presence in the community.