It's that special time of day: You're back from lunch, full of greasy pizza from the joint next door to work, even though you promised yourself you'd start meal-prepping and packing lunches this week. Someone just put on a pot of your office's famously mediocre coffee, but it's nowhere near done brewing. You're at your desk, staring at your computer screen, and oh, no – your eyelids are drooping.

There's still a few hours left in the workday, but you've hit an afternoon slump and feel completely out of gas. Fortunately, productivity doesn't have to end mid-afternoon – you can make the most of the rest of your shift. Learn to recharge and push forward through that post-lunch lethargy.

Know Why it Happens

American Dietetic Association spokesperson Lona Sandon told WebMD the afternoon slump takes place due to our circadian rhythms, which dictate sleep patterns. This natural rhythm causes most people to start feeling sleepy around 2 or 3 p.m. Some cultures, such as in Spain, combat the afternoon lull with a siesta, while those of us in siesta-less cultures have to find alternative options.

Sandon suggested taking a break and resting in the mid-afternoon, if possible, to push past the slump.

Make Like a Leaf

Just as your office plants are wilting from lack of sunlight, so are you. Head outside for a few minutes and sit in the daylight, as suggested by Reader's Digest. Better yet, take a walk around the block, and even make a quick phone call to a friend or family member to help reinvigorate your mind. The sunlight-induced boost of Vitamin D works to suppress production of melatonin, the sleep hormone, and resets your body's internal clock so it knows it's time to stay alert, not droop to sleep.

Moreover, walking increases your heart rate, which in turn gives a boost of energy.

Freshen Up

Wash your face, brush your teeth or even change your shirt to emulate your morning routine and help wake up your mind.

If refreshing your body doesn't work, tackle your work environment instead. Clean out and organize your desk. Clear your email inbox. Though mindless, these chores might help you feel like you've accomplished a tangible task. Plus, reducing physical and mental clutter might leave you feeling energized and more ready to take on your afternoon workload.

Skip the Pizza

It's unfortunate, but true: What you eat at lunch affects your energy levels through the rest of the day. Fast carbs, like those found in pizza, French fries and white bread, might spike your blood sugar temporarily, but your levels will plummet shortly thereafter, according to an article in Inc. Instead, opt for a lunch chock-full of fiber-rich vegetables, beans and pasta to help sustain your energy levels. (In other words: That greasy pizza next door might ruin your afternoon, but a burrito bowl from Chipotle is probably OK.)

Take things a step further and push through your sugar cravings, which once again might briefly spike your blood sugar levels but will ultimately cause you to crash. Stay hydrated, as well.

Take Mini-Breaks Through the Day

If you push yourself without breaks for the first four hours of your workday before stopping for lunch, that afternoon lull might hit you even harder. Conserve energy by making time for mini-breaks regularly through the workday. Take a lap around the block. Find an excuse to walk up and down the stairs. Even just stand up and stretch. A few moments away from screens and to-do lists can work wonders for your energy levels over the course of a day.