“The average full-time worker doesn’t even start doing real work until 11:00 a.m.,” he writes, “and begins to wind down around 3:30 p.m.”

The Microsoft survey pointed to worthless meetings.

What appears to be wasted time is really jell time.

“The longer you work, the less efficient you are,” said Bob Kustka, the founder of Fusion Factor, a productivity and time-management consulting firm in Norwell, Mass. He says workers are like athletes in that they are most efficient in concentrated bursts. Elite athletes “play a set of tennis, a down of football or an inning of baseball and have a pause in between,” he says. Working energy, like physical energy, “is best used in spurts where we work hard on a few focused activities and then take a brief respite,” he says.

And those respites look an awful lot like wasting time.