Twenty years ago, performance nutrition meant water and a banana. Today, it more closely resembles a science experiment, with neon-colored gels, powders, gummies, and an endless stream of protein and energy bars. That leaves many people (including us) overwhelmed and confused, so we set out to determine what to eat and when to eat it.
“The two most important factors to think about with these foods are the glycemic load and absorbability,” says Megan Forbes, a registered dietitian and founder of Forbes Nutritional Consulting. That means you need to consider a food’s nutritional profile—what’s in it and how long the energy it contains will last—and how quickly your body can digest and then use that energy.
There’s a guiding principle to sports nutrition: Easily digestible carbs are best for short, fast efforts, while more complex foods higher in protein and fat are good for slow, all-day excursions. To help you sort out where today’s most popular performance foods fall, we created a matrix that ranks 19 of those items.
We looked at absorbability (ten means the food is easy to digest and quick to absorb; one indicates the food is tough to digest and slow to absorb) and nutritional quality (ten means it’s high in nutrients like simple carbs that make for excellent performance fuel during high-intensity efforts; one means it has higher fat, protein, or fiber content that makes it less ideal for high-intensity efforts). A disclaimer: Since this is a ranking based on performance foods, we’re not saying lower-ranked foods are generally worse for your health; they’re just not helpful for all-out training efforts.
Best for Immediate Energy
In the not too distant past, your only hydration options were water or the sugar gut-bomb that is Gatorade. But the market has exploded in recent years, with manufacturers like Tailwind, Skratch Labs, and Gu Roctane tailoring their powders for ideal endurance hydration. Many of these mixes are packed with carbohydrates, sugar, and some salts, giving athletes the essential electrolytes and calories they need rather than just an overdose of sugar. And with a really high absorbability, they’re in and out of your system in the blink of an eye, perfect during intense efforts. “I think many people have the misconception that they want complex foods during activity. That’s backwards,” says Steph Violett, a champion ultrarunner with a PhD in nutrition. “That is the time you actually want the most simple sugar you can get. It will go directly to the working muscles to be used for energy.”
Gels have everything the body needs when your heart rate is skyrocketing and your body is blowing through energy—simple sugars, sodium, and electrolytes. They’re endurance-athlete rocket fuel, providing an almost instant boost. By that same token, they’re used up almost just as quickly. So, during prolonged intense efforts, it’s key to eat gels early and often to prevent emptying your energy reserves.
With a few more calories per package and a slightly slower absorption rate, think of performance chews—like Clif Shot Bloks or Honey Stinger Chews—as an incrementally longer-lasting gel. They too are typically packed with sugar, potassium, and sodium, but they require just a little more time for the body to digest than a near-liquid gel.
Homemade performance foods are having a moment. Specifically, rice-based, bite-sized homemade energy balls filled with ingredients ranging from eggs and ginger to dates and chocolate chips. With its moderately high glycemic index, rice helps athletes refuel similarly to straight sugar—quickly and easily—says Forbes. Although energy balls can vary widely in terms of their specific makeup—a quick Google search reveals thousands of recipes—it’s still hard to hit all the same nutritional markers with something you whip up in your kitchen as you can with a perfectly calibrated lab-designed chew or gel. That means these are ideal during long, moderate efforts, like an ultramarathon or a big bike ride, when you’re craving real food but are working too hard to stomach anything especially high in fiber, fat, or protein.
With heaps of sugar and usually caffeine, soda has become a surprising and counterintuitive performance food for ultramarathoners. Coke and Sprite are among the most popular items at any aid station, and many people swear by them as the miles start to add up. But be warned: Relying on the carbonated goodness for too long will leave you short on key electrolytes and sodium.
Best for Somewhere in Between
Sour and gummy candies are easily absorbed and loaded with sugar energy. But without much else in terms of vital nutrition—like the sodium or electrolytes often included in gels or drink mixes—you run the risk of bonking pretty quickly if this is your sole source of fuel. If nothing else, Violett says the best thing about candy is that it breaks up the performance-food monotony. “Sometimes it sounds way more appealing to eat Swedish Fish than a sleeve of blocks.”
While real fruit has a lower glycemic index than dried fruit, meaning it will provide less immediate energy in the form of carbohydrates, it is often a lot more complex and rich in terms of nutrients. Plus, more water content means a bonus of hydration. But Violett warns that fruit is high in fructose and fiber, which can sit in the gut and cause distress. So while fruit is relatively easily absorbed and will give you immediate energy, it’s best to save it for moderate to slow efforts.
During a cold, long mountain race, there is almost nothing more satisfying than a cup of broth. There’s a reason it’s spooned out at nearly every ultramarathon aid station: Broth provides hydration and replenishes lost salts. But Forbes warns that broth has little in the way of calories and, if not taken with other foods, may mess up an athlete’s salt balance.
Best for the Long Haul
Potatoes are a deceptively great performance food. They’re high in potassium, which can help balance your electrolyte needs, as well as tons of minerals, vitamins, and more than 30 grams of carbs, says Forbes. Ultrarunner Nickademus Hollon, who finished the notorious Barkley Marathons at age 22, told Outside in June that he runs with salty mashed potatoes in a plastic bag, squeezing globs out as needed.
The Dutch have been eating the stroopwafel—two thin layers of baked dough sandwiched around a sweet, syrupy interior—for more than 200 years. The concept has recently been co-opted by sports nutrition companies like Gu, Honey Stinger, and UnTapped, which have created their own performance-oriented waffles. They tend to have the same sugar and carbohydrate content, with added sodium and amino acids to help repair damaged muscles. The catch, though, is that many of these stroopwafels contain fat, making them hard to digest at high intensities. These waffles are best to eat before activity or early on during longer efforts.
Among European athletes, cheese is almost more popular than gels. This makes sense: A lot of European races are in or near the Alps, with inclines and grades far steeper than pretty much anything you’d find in the United States. As such, racers are often hiking and moving slowly. For this type of movement, cheese, which is usually quite hard to digest, is the perfect fuel. “It’s got a little bit of fat, a bit of protein, a tiny bit of carbohydrate. And it’s got salt,” says Forbes.
Violett agrees. “I think it works at UTMB and other European races because there is so much less intense running involved,” she says. “But in the U.S., I can’t think of a race where I’d use cheese.”
For years, the good ol’ peanut butter and jelly sandwich has been the secret weapon for just about everyone. The combination of fat from the nut butter, sugar from the jelly, and carbohydrates from the bread make this centuries-old sandwich a virtual do-everything performance food. The only downside, according to both Forbes and Violett, is that the sandwich is fairly hard to digest given the fat content of the peanut butter and the bit of protein that comes in baked bread. It’s perfect for the long, sustained hike, or as prerace fuel before an intense effort.
The energy bar is perhaps the most old-school performance food, albeit not necessarily the most effective one. Whether that’s Clif, PowerBar, Bobos, or ProBar, these grain-, oat-, or fruit-based bars have a good amount of carbohydrates and sugar for immediate energy, some fat and protein for longer-lasting fuel, and a bit of sodium and electrolytes to help replenish what the body loses in sweat. It’s for this same reason, though, that these types of bars are not ideal for the super high-intensity racer—there’s too much going on. Energy bars are optimal for the slow burn out on the trails or all-day ski.
“I think bars are wonderful for a pre-run snack or post-run,” says Violett. “But [during intense exercise] you don’t really want something that takes time to digest.” As this bar toes the line between slow-burning and quick-acting performance food more than almost any other item on this list, it’s important to know your body well before you make them a part of your race-day nutrition plan.
It’s hard for the body to break down and utilize protein when the heart rate is high, which is why Forbes reserves protein bars—options like Clif’s Builders and Quest Bars, both of which have more than 20 grams of protein—for easier activities where the intensity is generally lower than it would be during a serious training effort or race. “[Protein bars] would be great while hiking or even skiing,” she says. “Even like in between weight-training sessions, or prior to weight training, your protein bars would be ideal.” Generally, though, it’s best to save these dense bars for recovery or as a light meal replacement.
Best for Pre- and Post-Race
Sure, there is something supremely satisfying about the salty crunch of a chip, especially while on the trail. But in terms of its viability a performance food, not so much. High fat content from the frying process makes chips difficult to absorb. And you’re not really getting a significant amount of any macronutrient from a normal serving of chips. Think of chips as a taste treat—fun to munch on and potentially helpful in settling an upset stomach, but far from ideal for sustained performance nutrition.
Meat Bars and Jerky
Jerky has been a staple trail food among hikers for years. Recently, with the rise in popularity of high-fat, low-carb diets, the meat snack market has exploded, with companies like Epic and Krave creating bars and jerkies from bison, turkey, chicken, and pork, to name a few. It’s generally best to save these for recovery, meal replacement, or very long, easy hikes, when your slow-moving body has the ability to break down and use the dense protein. Violett sums it up: “This is not a performance food.”
The baked good—like a bagel, biscuit, scone, or tart—has been the go-to pre-run or ride fuel for centuries. And for good reason: Most pastries are tasty and packed with carbohydrates and sugar. You’ll probably want to reserve these treats for pre-training fuel, though, as the higher fat content in things like a scone and croissant makes it harder for your stomach to break down and put to work during exercise. Plus, without any significant amounts of sodium, electrolytes, or amino acids, baked goods won’t do much for the exercising body beside give it a quick rush of energy.
Chocolate has for some time been touted as a superfood—a deceptively healthy treat for the heart and brain, supplemented by studies showing that its high antioxidant count—epicatechin, in particular—helps blood flow and thus endurance performance. For the most part, this is true, but both Forbes and Violett warn against eating too much chocolate while you’re actually exercising. The high fat content and variability between different types of chocolate—not to mention the contents of different chocolate candy bars—make the treat a gamble to eat while the heart rate is high.
Sprinkled in nearly every type of trail mix and a staple among hikers, dried fruits like raisins, mango, apricots, and dates are loaded with natural sugars and will give anyone on the move a pick-me-up. However, since dried fruit so condensed, “it is tougher to absorb than real fruit and requires much more water to process,” says Violett. “Not super ideal during activity for that reason. Save the dried fruit for less active times, like backpacking or at rest.”