5 Ways to Get a Natural Energy Boost at Work Coffee is not the answer to the 3 o'clock slump.

We're all familiar with the energy slumps that can turn a productive workday into a tedious slog. Energy zappers can take many forms, from lack of sleep to family stressors or professional overwhelm. Whatever the cause of workplace lethargy, one thing's for certain: When you're trying to get work done, you need to get your energy back fast.

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While many of us reach for caffeine when we're feeling tired at work, this is a band-aid solution at best -- and it leads to even bigger energy crashes when the caffeine wears off. Whenever possible, you're better off turning to more sustainable strategies like these five natural energy boosters.

1. Guzzle water.

Even mild dehydration can contribute to a range of energy-draining symptoms including mental fuzziness, headaches, dizziness, lethargy and sleepiness. Downing plenty of water throughout the day is a simple and effective way to maintain energy and focus. If you feel your energy dip at any point in the day, try reaching for a glass of water before hitting up the vending machine for a candy bar.

2. Straighten up.

When we're tired at work, many of us have a tendency to slump in front of the computer. Our neck, shoulders and upper back round, and we sink further and further into our chair as the day goes on. Assuming this defeated posture can actually make us feel even more lethargic than we were before we sat down to work because it limits blood flow to the brain.

Whenever you catch yourself slumping, commit to sitting up straight. Not only is using better posture easier on your spine, but it will also keep energy flowing through your body. Better yet, stand up, and take a short stretch break every time you find yourself in a (literal) slump. Return to your desk with newly invigorated posture.

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3. Down a dose of nutrients.

One of the quickest ways to brighten up your mind is with a shot of good-for-you nutrients. While a healthy breakfast and lunch are good starts, you can achieve an even more immediate boost by drinking your greens -- in the form of green juices -- or consuming other "brain boosting" supplements such as nootropics. Nootropics have been used by everyone from young entrepreneurs all the way up to Silicon Valley hotshots to gain a mental edge.

4. Take a walk.

Getting up from your desk and taking a stroll -- whether that entails winding through cubicles or heading outside -- will provide a lasting energy boost. That's because physical movement gets your blood circulating and can trigger the release of energizing chemicals in the body. Not only does taking a short walk increase your energy, but it's also been shown to stimulate creative thinking and problem solving and contribute to a more positive mood.

While you'll experience these benefits no matter where you walk, heading outside will provide you with an additional energy lift thanks to the sun, which can have an uplifting effect both physically and mentally.

5. Remove one thing from your to-do list.

One of the biggest contributors to feeling exhausted at work is a pervasive sense of stress or overwhelm. An oppressive work schedule can zap us of our energy and leave us on the downward slope to burnout. Thus, one of the quickest ways to feel lighter and more energized is to free yourself of one or several of your obligations at work.

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Start small by delegating tasks whenever possible, asking a coworker to pitch in on a particularly overwhelming project, or meeting with your manager to discuss how to develop a more manageable workload. Simply freeing yourself from one to-do list item or knowing that you and your manager are working on a solution to the problem of over-work will instantly infuse your day with more energy.

Whenever you're feeling groggy or exhausted at work, turn to these five strategies for an instant and lasting dose of natural energy.