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Riding a century is like a rite of passage in cycling. So is “bonking” (draining your energy stores from poor fueling). Not surprisingly, the two often go hand-in-hand when riders stretch their mileage into triple digit territory.
Done properly, 100 miles on your bike is a (mostly) enjoyable experience (there will always be those low moments). Done improperly, that last 20 to 30 miles can be one of the longest, most painful stretches of road in your life. But by understanding the concepts of fueling and pacing, you can fend off this beast for your first and/or next hundo.
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How to Fuel a Century Ride
First and foremost, plan to consume carbohydrates during the course of the ride. The faster you go, the more fuel you’ll need because you’ll be burning more. But you’re still dipping into your glycogen stores, burning about 1 gram of glycogen a minute, at low, “fat-burning” intensities, says Iñigo San Millán, Ph.D., head of trainers staff for UAE Team Emirates and researcher at University of Colorado School of Medicine.
You only have 350 to 500 grams (max) when your stores are fully stocked. That’s about 1,700 calories worth, which you’ll run through in about 3 to 4 hours (or less) of moderate riding. Aim to top off your tank with 30 to 60 grams of carbohydrate (the lower end for light riders; the higher end for larger riders) an hour.
As you know, there’s a wide array of pre-packaged fuel sources like bars and carbohydrate gels that are portable, easy to digest, and come in a wide variety of shapes, sizes, and flavors. A typical energy bar can consist of about 200 to 250 calories, 30 to 40 grams of carbohydrate, 10 grams of protein, and 5 to 10 grams of fat. Carbohydrate gels run in the 100- to 125-calorie range and consist of 25 to 30 grams of a more easily digestible and simple carbohydrate source. (Just make sure to follow the directions and always wash down gels with at least 8 ounces of water to dilute them for quick absorption. Also, do not take gels with sports drink; it increases the sugar concentration in your gut, slowing absorption, and causing stomach upset.)
While bars and gels can do the trick, it’s tastier and more nutritious to fuel your century ride with real food like peanut butter & jelly sandwiches, bananas, fig bars, Peanut M&M’s, trail mix and other food you like. Regardless of what foods you choose, take the time to experiment with all your snacks during training to get to know how both your energy level and digestive system will respond to your choices. Mile 73 is not the time to discover you really can’t stomach Sour Patch Kids on a ride.
Fluid consumption is even more important than food intake. Even minor dehydration hurts performance. Aim to consume at least one 20-ounce water bottle per hour while using a combination of sports drink and water.
Sports drinks can serve a dual purpose for the century cyclist: hydration and carbohydrate intake. Just be aware that sports drinks with more than 8 percent carbohydrate (also known as hypertonic because they’re more concentrated than your blood), like GU Roctane are designed to be like “liquid fuel” and provide calories with your hydration. But they’re slower to move out of your gut and into your bloodstream than more dilute drinks, so don’t rely on them for hydration. Have a bottle of just water or an electrolyte drink in your second bottle, as directed on the packaging.
For both foods and fluids, eat and drink early and often. A 100 miles is a long time to be on the bike and can take more than 8 hours depending on the terrain. Most Century rides have planned rest stops where you can fill your bottles and grab some food. Take full advantage of these stops. What you eat and drink during hours two and three of your event will dictate how you perform in hour four, five, six, and beyond. It’s a much easier task to keep the fire going by being attentive to your fuel intake versus trying to recharge an extinguishing flame.
Your Century Ride Fuel Plan
The following is a century ride fuel plan. Please keep in mind that energy intake is extremely variable and depending on your size and the speed you ride, you may need fewer or more calories. This is meant to be a starting point for a 150-pound rider averaging about 15 mph. But you may need to tweak it according to your specific needs.
Two days out:
Stock your stores. To start the ride with as much glycogen in your muscles as possible, shift your diet to have a higher percentage of carbs for 24 to 48 hours before your ride. For instance, if you usually eat chicken and vegetables for dinner, cook up a stir fry that you can put on a bed of rice as the base.
Pro tip: Pull up the event registration/information page and check out where the aid stations will be located and what food/drink to expect. That way you’ll know what to expect and whether or not you need to pack more of your own food/hydration mix to be sure you have what you need and like.
Event morning:
Eat a good breakfast that fills you up without leaving you stuffed. Oatmeal is the perfect pre-century meal because it’s easy to digest, yet it gives even, lasting energy. Add some nuts or nut butter and/or a little yogurt for a bit of protein and fat. Wash it down with coffee (if you like caffeine in the morning), and you’re ready to roll.
Pro tip: The porta potty lines can be long at event venues. If possible, eat about two hours before go time, leaving yourself enough time to digest and take care of morning bathroom business before you line up to ride.
Rest stop #1 (~20 miles):
You shouldn’t be too depleted yet. An energy bar or other baked good will provide the 30 to 60 grams of easily digested carbohydrates that you need to top off your tank.
Pro tip: Even if you don’t really need anything at this point, it’s wise to stop and at least top off your bottles. You never know what’s coming up. Flat tires, going off course, harder than anticipated sections can mean you have to ride longer than planned to the next aid station and you can find yourself thirsty and hungry with empty bottles and pockets.
Rest stop #2/Lunch (~45 miles):
By now your muscle glycogen stores are getting depleted. A rest stop PB&J with some potato chips is a good lunch.
Pro tip: Take your time and grab a bite, but you might want to avoid dawdling too long. The longer you sit around, the harder it is to get rolling again. (And if you do choose to chill for a while, just give yourself a little longer to warm back up.)
Rest stop #3 (~65 miles):
When riders hit the wall it’s often here in no man’s land. You’re not close enough to being done to get juiced up. You’re too far in to be fresh. A little caffeine can help perk you up. Now’s a good time for a mini Coke, a chocolate treat, or caffeinated sports chews.
Pro tip: You might also be kind of sick of sweet snacks at this point. Salty peanut butter crackers, trail mix, Pringles, or pretzels can replenish some of the salt you’re sweating out while also helping you avoid palate fatigue from all the sugar.
Rest stop #4 (85 miles):
Your sweat losses can really catch up to you here. It’s important to have a sports drink right about now.
Pro tip: Tempting as it may be, do not blow off the final aid station. In fact, the closer that aid station is to the end, the more important it is for you to stop and top off your bottles and maybe grab a bite. The event promoters often put those final aid stations in because there are some challenging miles ahead that may take riders longer than they expect.
The finish (100 miles!):
Whoo-hoo! Celebrate with a high-carb, moderate-protein meal within 30 minutes of stopping to restock your glycogen stores while your muscles are at their hungriest.
Pro tip: Focus on a 3:1 carb-to-protein ratio for maximum glycogen stocking. Good examples include a turkey sub, grilled chicken pasta salad, or a hummus and grilled veggie wrap.
