Editorial: Conquering Fatigue

This is an expanded version of the Editorial that appeared in the print version of Chemical Engineering Progress, April 2017.

I scan a daily digest of press releases that I receive to get ideas for my editorials. One recent headline caught my attention: “Conquering Mental Fatigue.” I printed the release along with a few others I wanted to read. Only after I retrieved it from the printer did I notice that the title was “Conquering Metal Fatigue.” Metallurgists discovered that incorporating a laminated nanostructure into steel makes it more resistant to fracturing under repeated stress. Although interesting (see news story, pp. 7–8), it was not what I was expecting based on my initial reading of the headline.

Most of us have experienced mental fatigue — the feeling that “my brain is tired” — after activities that require an extended period of concentration, such as listening to a long technical presentation or reading complicated material. (We hope CEP doesn’t contribute to your mental fatigue.) Mental fatigue can manifest as lethargy, sleepiness or sleeplessness, anxiety, irritability, or difficulty concentrating and solving problems, even simple math.

On Amir, an associate professor of marketing at the Univ. of California, San Diego, wrote in Scientific American that the brain is like a muscle: When you focus on a specific task for an extended period of time, you are flexing your executive function muscles, which draws upon a single resource of limited capacity in the brain. “When this resource is exhausted by one activity, our mental capacity may be severely hindered in another, seemingly unrelated, activity,” he said. “Unrelated activities that tax the executive function have important lingering effects, and may disrupt your ability to make an important decision.”

It’s not only strenuous cognitive tasks that can tire your brain. Kathleen Vohs, a professor of marketing at the Univ. of Minnesota, demonstrated that decisions as simple as making a choice may deplete executive resources. Making decisions — whether [even] simple, noncontroversial decisions with relatively minor impacts like what to wear to work or eat for breakfast, or more consequential ones like where to build a new plant or how to restructure your company — causes a type of mental fatigue known as decision fatigue.

Some of the research on decision fatigue has looked at decisions related to self-control, or willpower: Should I write my editorial or watch TV? Should I buy that expensive dress or keep walking to the sock department and get what I came for?

Through a series of experiments, Vohs and her colleagues found that “making choices depletes a valuable internal resource that is needed for self-regulation, and thus self-regulation is impaired in the aftermath of decision-making.”

Social psychologist Roy Baumeister of Florida State Univ. has studied the link between willpower and glucose. Blood glucose provides the energy the brain needs for self-control, and acts of willpower deplete relatively large amounts of glucose. Take heart, though. Research also suggests that restoring glucose to a sufficient level typically improves self-control and decision-making ability. I wonder if the advertising agency that developed the “Have a Snickers … You’re not you when you’re hungry” campaign knew about this work?

I wouldn’t recommend eating a candy bar every time you face a decision (although I might allow myself a Hershey’s Kiss, a couple of M&Ms, or a Munchkin on occasion). But there are several other strategies that can help prevent mental fatigue:

• Know your limits. Writer Brian Bailey advises: “Build different types of work into your schedule so you can avoid making decisions for hours in a row. If you’re facing a big decision, try to process it early in the day and after a meal so that you’re at your peak mentally. On days when you feel the effects of decision fatigue, avoid situations where a poor decision could have significant repercussions.” Avoid back-to-back-to-back meetings.
• Make fewer decisions. Former President Barack Obama said in an interview in Vanity Fair, “You’ll see I wear only gray or blue suits. I’m trying to pare down decisions. I don’t want to make decisions about what I’m eating or wearing. because I have too many other decisions to make.” By keeping basic, routine decisions simple (or eliminating them altogether), and by delegating decisions to others whenever possible, we have more mental energy to deal with the rest of the day.
• Develop and use checklists. When airplane pilots run through a preflight checklist, they can focus on checking the items on the list rather than worrying about forgetting something important.
• Plan your day. Before leaving work today, plan what you will do tomorrow.
• Use the timebox technique, in which you allocate a fixed time period, called a timebox, to each planned activity. Leadership coach Bruna Martinuzzi notes that timeboxing forces you to limit the time you allot to certain tasks that run the risk of taking far more time than they’re worth, and it forces you to do the best job you can within a set time frame.
• Don’t make major decisions after you’ve spent a long time focusing on a particular task, exercising self-control, or even making many seemingly minor choices. If you are facing an important decision, like whether to accept a new position or shut down an operating facility, make it first thing in the day, when you’re well-rested and the glucose levels in your brain are highest.
• Get moving. Exercise is known to restore mental focus and improve concentration. If you can do it outside, in fresh air, among nature, that’s even better.
• Get a good night’s sleep. The National Sleep Foundation recommends 7–9 hours per day.
• Relax. After a workout, athletes let their muscles recover. It’s important to also let our brains recover from the mental exertion involved in a chemical engineering career. Take time off, maybe a Friday or Monday for a long weekend.

To read more on this topic, I recommend John Tierney’s New York Times article “Do You Suffer from Decision Fatigue?”