Ms. Ryan and Ms. Markova have found what they call three zones of existence: comfort, stretch and stress. Comfort is the realm of existing habit. Stress occurs when a challenge is so far beyond current experience as to be overwhelming. It’s that stretch zone in the middle  activities that feel a bit awkward and unfamiliar  where true change occurs.

“Getting into the stretch zone is good for you,” Ms. Ryan says in “This Year I Will... .” “It helps keep your brain healthy. It turns out that unless we continue to learn new things, which challenges our brains to create new pathways, they literally begin to atrophy, which may result in dementia, Alzheimer’s and other brain diseases. Continuously stretching ourselves will even help us lose weight, according to one study. Researchers who asked folks to do something different every day  listen to a new radio station, for instance  found that they lost and kept off weight. No one is sure why, but scientists speculate that getting out of routines makes us more aware in general.”

She recommends practicing a Japanese technique called kaizen, which calls for tiny, continuous improvements.

“Whenever we initiate change, even a positive one, we activate fear in our emotional brain,” Ms. Ryan notes in her book. “If the fear is big enough, the fight-or-flight response will go off and we’ll run from what we’re trying to do. The small steps in kaizen don’t set off fight or flight, but rather keep us in the thinking brain, where we have access to our creativity and playfulness.”

Simultaneously, take a look at how colleagues approach challenges, Ms. Markova suggests. We tend to believe that those who think the way we do are smarter than those who don’t. That can be fatal in business, particularly for executives who surround themselves with like-thinkers. If seniority and promotion are based on similarity to those at the top, chances are strong that the company lacks intellectual diversity.

“Try lacing your hands together,” Ms. Markova says. “You habitually do it one way. Now try doing it with the other thumb on top. Feels awkward, doesn’t it? That’s the valuable moment we call confusion, when we fuse the old with the new.”

AFTER the churn of confusion, she says, the brain begins organizing the new input, ultimately creating new synaptic connections if the process is repeated enough.