7 things successful people do during an afternoon lull

"If you don't take an intentional break, your body will take an unintentional one for you," Vanderkam says. "Go for a walk. Get some fresh air."

Kerr says numerous health experts are "warning of the dangers of people sitting too long, some even calling it 'the new smoking' in terms of its potential health threat."

Taking a walk will get your muscles moving and the oxygen flowing, and it also allows you to clear your head. "Plus, getting some fresh air will not only help wake you up, but if you've been working on a computer, focusing your eyes on longer distance objects can help minimize eyestrain — and getting some sunlight can help reset your clock," Kerr adds.

When the energy boost you get from lunch starts wearing off, you tend to experience a wave of sleepiness, Vanderkam explains.

To avoid that, successful people eat something healthy to perk them up a bit. "Snack on something that isn't too high in sugar, like cheese or fruit," she says. "You don't want to crash again 20 minutes later."

Sleep experts agree that an afternoon cup of coffee does help maintain alertness, as long as you don't overdo it, Kerr explains. If you're not a coffee drinker, then try green tea or water.

"Keeping hydrated helps maintain energy levels throughout the day," he says. "Regardless of what you drink, use a beverage break as an excuse to get away from your desk, walk around, stretch, and interact with some people — all things that will help you maintain your energy levels."

The most successful people turn the lull into a creative advantage by taking a power nap, Kerr explains. "Some of the greatest creative minds, most notably Thomas Edison, were or are huge fans of naps, believing that naps not only allow them to be more productive, but that they also helped them to be more creative."

It may be difficult to nap at work — especially if you work in a cube or an open space — but if you can find a quiet place to rest for 15 minutes, you could be doing yourself (and your employer) a huge favor.

A few upbeat songs can easily lift you up, get you moving, and provide a much-needed distraction to help you clear your head, says Kerr.

If you've got a flexible job or you work from home, the mid-afternoon slump is a great time to work out. "Exercise is energizing, and when you return, you'll likely be able to focus for another few hours," Vanderkam says.

Kerr says if you're not able to do a "full-on workout," taking 10 minutes to stretch, do some yoga, or walk around the office can help, too.

"Successful people are masterful at managing their time and priorities, and to do that effectively you need to plan effectively ahead of time for the afternoon slump: getting a good night's sleep, maintaining a fitness regime, and eating healthy will all help," Kerr says. "But you also need to become aware of your own energy cycle so that you adapt your schedule to your own body's rhythms as needed."