From 2007 to 2011, Novak Djokovic ranked a distant third to Roger Federer and Rafael Nadal. Despite his elite skills, he was prone to cramping and low stamina, making him vulnerable during long, five-set matches.

In 2011, a nutritionist completely revamped Djokovic’s diet – adding some things, removing others, and focusing on eating strategically to optimize his performance. Soon he began to win the five-set matches (which he had previously lost) while looking fresher at the finish. On July 6, 2014 Djokovic won his second Wimbledon title and is currently world champion.

But why is Djokovic’s story important to someone whose sport is working 10- to 12-hour days in an intensive job? While elite athletes rely on strategic eating to fuel their bodies, we desk jockeys should consider doing the same by intelligently fueling our brains.

We all strive to be sharp during the workday—to stay energized, maintain focus, and make good decisions. However, in the early afternoon it’s natural for blood sugar levels to drop and for energy and mental performance to suffer. Our response is to snack, but when we don’t do so thoughtfully, we crash and our performance suffers even further.  A study in the journal Nature Reviews Neuroscience highlighted how specific nutrients affect brain performance. For example, omega-3 fatty acids (found in fatty fish, walnuts and chia seeds) improve cognition, while trans fats (found in certain baked items and processed snack foods) impair it. Antioxidants, particularly those found in berries and cherries, provide protection from free radical damage. And flavanols, like those in cacao (think cocoa powder, cacao nibs and dark chocolate), can improve memory. Whether our workplace is the tennis court or an office building, it is clear that nutrition impacts performance.

With that in mind, strategic snacking is key to winning the five-set match we play each and every day. These between-meal munchies should contain combinations of high-quality carbs, protein, fats and micronutrients to help level out blood sugar, sustain energy and keep us feeling sharp and focused. By choosing nutrient-rich snacks like Greek yogurt, nuts and fruit instead of sugar-filled candy bars and donuts, we can actually improve the way our brains work. Planning snack times and having strong options readily available make the difference between sustaining mental performance and crashing during long and intense sessions at the office, or on the court.

Below is a list of brain-enhancing ingredients. Of course, making sure these vital picks are easily accessible during the day is entirely up to you!

• High-quality carbs: quickest source of energy for the body; brain’s preferred fuel. Your best bets are fruits, vegetables, legumes, whole grains (oats, quinoa, etc.)
• Healthy fats: decrease inflammation; improve circulation to brain; maintain cell membrane integrity and function. Your best bets are olive oil, avocado, nuts, seeds (sunflower, pumpkin, flax, chia), coconut, fish
• Protein: regulates blood sugar levels; revs metabolism; keeps you feeling full and satisfied. Your best bets are beans, nuts, seeds, poultry, fish, low-fat dairy
• Fiber: regulates blood sugar levels; promotes regularity; keeps you feeling full and satisfied. Your best bets are fruits, vegetables, nuts, seeds, beans, whole grains
• Antioxidants: decrease inflammation; improve circulation to the brain. Your best bets are fruits, vegetables, herbs, spices, dark chocolate, cocoa powder.
• Caffeine: improves focus, concentration and alertness. Your best bets are coffee, tea, dark chocolate, cocoa powder