If late nights at work leave you groggy and ill-equipped to deal with a morning brainstorming session, here's why: The best ideas come from a healthy, rested brain.

Despite the lore that bad habits go hand in hand with inspiration—think of Ernest Hemingway, Vincent Van Gogh and other creative legends—research points in the opposite direction, says Daniel Amen, CEO of the Amen Clinics, which specialize in brain research. Amen believes that these hard-living artists were creative despite their lifestyles, not because of them.

Although scientists are only beginning to study the specific links between health and creativity, current research (not to mention common sense) suggests that for most of us, stress, sleep and fitness are key factors that influence our creativity. IT leaders who work long hours (such as the 24 percent of respondents to a survey by recruitment firm Harvey Nash in March who said they clock more than 56 hours a week) may not be at their best and most creative at a time when innovation is increasingly important.

Stress Kills Brain Cells
Continuous or intense stress can harm brain cells, brain structure and brain function, causing such side effects as memory problems or depression, according to neuroscientists.

Animal research offers clues about stress's effect on the brain. In one study reported by the Society for Neuroscience, when researchers stressed rats by restraining them, cells in the hippocampus—a brain area important for memory—withered. Other studies indicate that stress inhibits brain cell replacement in the hippocampus, which is one of the few areas of the brain that can create new cells throughout one's life. Both phenomena could affect brain cell communication and memory.

Sentara HealthCare CIO Bert Reese says stress is an "unnecessary distraction" from his work. He takes care to manage it with preventive measures such as exercise and by focusing deeply on the task at hand. To stay creative, he places a premium on family and downtime. "It is important for me to have quiet time to just let ideas flow," he says.

Exercise Gives New Ideas a Boost
Best-selling novelist and marathoner Haruki Murakami says running fuels his creativity. And if you've ever had that feeling of giddy invincibility after a great run or bike ride, you know exercise can make you feel sharper.

In the short term this is because exercise lowers stress, boosts blood flow to your brain and releases endorphins—neurotransmitters that suppress pain and give your body the feeling of a natural high.