This drowsy feeling is temporary but frustrating. Experts have ways to cope.
Here’s how the story may go: You wake up in the morning ready to tackle the day. You’re in a groove. You’re getting things done. But then the clock strikes 2 p.m., and you’re hit with a wave of fatigue. Suddenly, a nap feels tempting.
In these moments, you may be experiencing what some people call an afternoon energy slump.
“It’s really important for people to understand that this is normal physiology,” said Stephen Justin Thomas, president of the Society of Behavioral Sleep Medicine. Some places around the world embrace our natural inclination to rest in the afternoon by temporarily closing businesses or setting aside time to relax, Dr. Thomas said.
But it’s not always possible to sneak in extra shut eye in the middle of the day. Here’s the science behind this energy dip and ways to manage it.
What causes the afternoon slump?
Sleepiness is widely believed to be influenced by both circadian rhythms and sleep pressure, said Dr. Ian Katznelson, a neurologist at Northwestern Medicine Lake Forest Hospital.
Circadian rhythms dictate how bodily functions ebb and flow over a roughly daylong cycle, experts said, and these rhythms are largely set by a biological “clock” in the brain. Sleep pressure, meanwhile, is the idea that our need to sleep gradually builds the longer we’re awake.
Our circadian rhythms are influenced by the environment, which means we generally feel awake and alert during daylight, and sleepier when it’s dark. But some fluctuations are normal: For instance, people tend to feel quite awake in the late morning, said Dr. Alon Avidan, a professor of neurology at the University of California, Los Angeles, but experience a dip in alertness in the afternoon — when certain neurotransmitters linked to feeling awake may become less active.