In my last column, I wrote about how I lead groups of volunteers to work with the Kenyan Children Foundation in Africa, and how we all return home exhausted but with our brains refreshed and renewed. We take a break from our usual ways of thinking and open our minds to new ideas and experiences. But you don't have to travel thousands of miles from home to recharge your brain.

As an entrepreneur, you probably work upward of 60 hours a week. Forbes interviewed 20 entrepreneurs about their work habits and found they worked an average of 60 to more than 100 hours per week. Most noted that weekdays were not much different from weekends, and that personal time off did not exist at all. One responded, "the concept of 'work' disappears--it is just what we do."

As anyone who has crammed for an exam can tell you, usually the number of hours we work without interruption is inversely proportionate to how much we accomplish. So how do these entrepreneurs manage to work so many hours without suffering from brain fatigue?

Well, first of all, it is because they truly love being an entrepreneur and are passionate about their enterprise. But, I believe, part of the answer is that they wear so many hats. They never get stuck doing the same kind of work for too long.

Here are some more brain-based tips that can work wonders and could be what helps propel entrepreneurs forward:

1. Buy a good office chair, or get a standing desk. 

Focal Upright Furniture has a brand-new chair-and-desk combination on the market. Invented by Martin Keen, of Keen shoes fame, it uses a position between sitting and standing, and allows lots of movement as you work. It also helps those who use it remain attentive.

2. Do not multitask.

John Medina, author of Brain Rules, tells us the brain cannot multitask, period. What it does do is switch back and forth between tasks very quickly. Someone whose attention is interrupted not only takes 50% longer to accomplish a task but also makes up to 50% more errors. A study in The New England Journal of Medicine found that people who talk on the cell phone while driving are four times more likely to have an accident, because it isn't possible to devote your full attention to both driving and talking at the same time. Hands-free calling offered no advantage. What's the lesson to take away? Focus on one task at a time, and you'll accomplish each better and faster--without killing anybody.

3. Use all your senses.

Work is more entertaining for your brain--and therefore makes you more alert--when you engage as many of your senses as possible. Use colored paper and pens. Experiment with peppermint, lemon, or cinnamon aromatherapy. Try playing background music.

4. Don't make too many decisions in one day.

It sounds farfetched, but if you go shopping in the morning, then negotiate yourself out of eating a cookie at lunch, and finally try to decide between two job offers that afternoon, you might choose the wrong job because you didn't eat the cookie, according to Scientific American. Making choices depletes your reserves of executive function, or "the mental system involved in abstract thinking, planning, and focusing on one thing instead of another." This can adversely affect decisions you make later.

5. Take a quick break every 20 minutes.

A study in the journal Cognition reveals that people can maintain their focus or "vigilance" much longer when their brains are given something else to think about every 20 minutes. That's the time when thinking becomes less efficient. This trick is called momentary deactivation. If your mind isn't as sharp after a long period of work, it may not be completely fatigued. It just needs to focus on something else to refresh the specific neural network you've been using.

6. Work with your own circadian rhythms. 

Are you an early bird or a night owl? Do you fade every afternoon, or is that when you are strongest? Don't schedule an important meeting at a time when you will be operating on one cylinder. And don't waste your peak work time at a doctor's appointment.

7. Relax for 10 minutes every 90 minutes.

When you're awake, your brain cycles from higher alertness (busy beta waves) to lower alertness (alpha waves) every 90 minutes. At that point, you become less able to focus, think clearly, or see the big picture. You know the signals: You feel restless, hungry, and sleepy, and reach for a coffee. Herbert Benson of Harvard, author of The Relaxation Response, recommends working to the point where you stop feeling productive and start feeling stressed. At that moment, disengage. Meditate, do a relaxation exercise, pet a furry animal, go for a quick jog, take a hot shower, pick up your knitting, practice the piano, or look at paintings. Allowing your brain to go into a state of relaxation, daydreaming, and meditating will reset your alertness.

8. Take power naps.

Researchers have found the human ability to learn declines as the day wears on. But an afternoon power nap increases scores on memory tests by 20%.

9. Experience nature--preferably real, but fake will do.

A walk in the park, a glance out the window at the trees, or even a view of nature photographs engages a different kind of attention than your normal work routine. According to a study titled "The Cognitive Benefits of Interacting With Nature," nature engages our involuntary attention. We hear a bird's song, feel a breeze, or notice the clouds moving across the sky in a manner known as effortless attention. We can concentrate much better after we have spent some time in a natural environment or paid "effortless attention." Walking around a city block doesn't count, given that that requires vigilance and directed attention, and does not give your brain a break.

10. Take a vacation.

One CEO recommends mountain biking, because it forces you to stop thinking about the office and to instead concentrate on staying alive. You probably feel that you can't possibly get away, but ultimately it will make you a better leader for your company.

Going to Africa--literally or figuratively--refreshes your brain, which allows you to be productive longer and to tackle more issues. Whether you need to review your budget, approve a marketing initiative, or hire people, you'll have the new perspective and alert brain you need to be your best.