I just finished reading a remarkable new book entitled When – The Scientific Secrets of Perfect Timing. It’s written by Daniel Pink, a brilliant, incisive, and delightfully readable author of three other must-read books focusing on career success: Drive, which draws on 50 years of behavioral science to overturn the conventional wisdom about human motivation; A Whole New Mind: Why Right-Brainers Will Rule the Future, which charts the rise of right-brain thinking in modern economies and describes the six abilities individuals and organizations must master in an outsourced, automated age; and To Sell is Human: The Surprising Truth About Moving Others, which uses social science to offer a fresh look at the art and science of sales. These books are among the most valuable of the hundreds I’ve read, each providing research-based insights that will improve performance not just at work but in other key areas of life (e.g. family, health, relationships).

When focuses on the effect that time of day has on mental performance across a broad range of categories. He reaches three key conclusions:

“First, our cognitive abilities do not remain static over the course of a day. During the sixteen or so hours we’re awake, they change – often in a regular, foreseeable manner.

Second, these daily fluctuations are more extreme than we realize. The performance change between the daily high point and the daily low point can be equivalent to the effects on performance of drinking the legal limit of alcohol…..research has shown that time-of-day effects can explain 20 percent of the variance in human performance on cognitive undertakings.

Third, how we do depends on what we’re doing. Perhaps the main conclusion to be drawn from studies on the effects of time of day on performance is that the best time of day to perform a particular task depends on the nature of that task.”

Analytical tasks, requiring linear thinking, are most successfully undertaken in the morning, while creative thinking, more amorphous and non-linear, is generally better in the afternoon. Why is this? Two primary reasons.“ First, when we wake up our body temperature slowly rises. That rising temperature gradually boosts energy level and alertness. Second, the stress hormone cortisol kicks in as we awaken to heighten vigilance, but declines as the day goes on. The result? A corresponding fall in the ability to remain focused and constrain inhibitions. Focus and inhibition can limit the free-ranging kind of thinking necessary to solve creative problems.

In support, Pink cites research that amazes: student test scores are higher in the morning, traffic accidents spike in the afternoon, surgical errors are significantly more likely in the p.m., etc.

Pink makes numerous recommendations on how to enhance productivity in the face of these biological realities. He’s a big fan of hydration. We lose a lot of water over the course of the night, so drinking a glass of water immeditaely upon arising helps wake us up faster. He’s also a big breakfast fan, for similar “restorative” reasons (“it fortifies our bodies and fuels our brains”).

Naps are something that he places great stock in (“the overall benefits of napping to our brainpower are massive, especially as we get older”), and offers some ideas on the best way to nap: short (10 – 20 minutes), and, oddly enough, preceded by a cup of coffee because caffeine, which takes about 20 – 25 minutes to kick in, helps arouse us from the lethargy that generally follows napping.

Taking frequent, short breaks has also been shown to enhance productivity. The ideal pattern appears to be an hour of concentrated work focus followed by a 15 minute break. The best kinds of breaks? Those that involve moving around (walking), that are social rather than solitary, that are taken outdoors rather than inside, and that are ones in which we as fully as possible detach from whatever it was we were previously doing. One particularly interesting study that he cites revealed that judges were far, far more lenient in granting a parole request after a break than before one.

What accounts for this phenomenon? When tired, we resort to a “default” mode of thinking that requires less mental energy. In that mode we are much more likely to follow a pre-existing way of looking at a problem, rather than analyzing the problem from a fresh perspective.

I will be sharing more insights from this fascinating book in my next post.