Welcome to the Mount Sinai Health Beat, a feature with the official medical provider of USTA Eastern, USTA, and the US Open. This month, Kelly Hogan, MS, RD, CDN, clinical nutrition coordinator, Dubin Breast Center at The Mount Sinai Hospital, talks about hydration and refueling before, during, and after playing tennis.

 

Many tennis fans were shocked when Serena Williams ordered an espresso after a lackluster first set at the Hopman Cup two years ago. After losing the first set at love, Serena gulped down the caffeinated beverage from a paper cup and went on to win the next two sets, the final at 6-0. This highlights both the use of caffeine as an ergogenic aid, or performance-enhancing substance, and an often overlooked ingredient of tennis play—hydration and fueling.

 

During intense, endurance activities like tennis, it’s important to be on top of your nutrition for optimal performance. ADVERTISEMENT What you should eat before practicing or a match depends on how much time you have before play. If there is a quick turnaround, 60 to 90 minutes, it’s best to eat simple, easily digestible carbohydrates that are relatively low in fat and protein. This gives the body a quick energy source without stressing the digestive system. A banana, English muffin, or oatmeal with a bit of peanut butter work well. If you have more time—three to four hours— quick digestion is not as much a concern. And you may be sustained for a longer time by a more substantial meal with some protein and fat, such as eggs with whole wheat toast and a side of fresh berries, or Greek yogurt with granola and sliced fruit.

 

Adequate hydration is also important. Even mild dehydration can hurt performance. What you drink and how much depends on your time on court and the temperature. If it’s cooler out and you’re hitting or practicing for a short time, then plain water works well. During a more intense practice session or a marathon match in warmer temperatures, a sports drink can help replenish the electrolytes—sodium, potassium, and magnesium—that we lose in sweat. Electrolytes help regulate muscle contractions. Any imbalance can increase the risk for heat-related muscle cramps and cause sluggishness during play. Dissolvable electrolyte tablets or sports drinks work well in these conditions. I recommend them over the more trendy coconut water in most cases. While rich in potassium, coconut water contains little sodium, the most important electrolyte to replenish.

 

Sports drinks also contain carbohydrates that our bodies can readily use as energy. This becomes more important the longer you play, as your glycogen—a reserve of glucose, our energy source—continues to burn. Like hydration, refueling during a match depends on how long you are playing. For light hitting or casual play, there is no need for a mid-play carbohydrate break. For matches longer than 60 to 90 minutes, however, you’ll want to take in some fuel to keep energy levels up. Aside from sports drinks, other easily digestible carbohydrates like energy gels/chews, bananas, pretzels, and dried fruit can work well.

 

A great fueling plan doesn’t end after you’re finished playing. What you eat and drink in the hours following play is essential to help the body recover and prepare for the next round. Within 30 minutes of a match or hard practice, the body is very efficient at replenishing glycogen stores and rebuilding broken down muscle fibers. This is an important time to refuel with both carbohydrates and protein. It can be something simple, like chocolate milk, a smoothie, or peanut butter on toast, until you can sit down for a more complete meal.

 

If you’re wondering whether caffeine might help, try a small dose before or during a longer practice. A Serena-inspired mid-match shot of espresso may not be available for all of us, but an energy gel or caffeine pill can have the same effect. For a 150 pound person, a moderate dose would equate to around 230 milligrams of caffeine. This is equivalent to about two cups of coffee. Most caffeinated energy gels have around 35 to 50 milligrams per packet, so spacing out your intake over a match is a good strategy. Keep in mind that caffeine has been studied to be most beneficial at boosting performance in longer endurance activities. Also, the more sensitive you are to caffeine, the bigger the effect it is likely to have. So if the Starbucks barista knows your name and daily order, adding more caffeine to your fueling plan may not make much of a difference.

 

While I’d never recommend this outside of endurance sports, soda can be useful during long matches or practices as well. Like sports drinks, sodas provide carbohydrates for quick energy and, if caffeinated, can provide an additional energy boost. Gael Monfils has requested a Coca-Cola in several matches throughout his career, and he may very well be onto something.