Dear Fuel School, I’m getting ready to run a half-marathon this weekend. If I need to carb-load, what should I consume before the start of the race, and how do I fuel to avoid hitting the wall mid-race?
Great questions! I too am gearing up for a half-marathon
this weekend and the Runner’s World Half-Marathon Festival
next month, so I’ve been busy planning my carb-load and pre-race breakfast. (When you’re a nutrition nerd, you tend to sleep, eat, and breathe race fueling.)
So first things first—the carb-load. You might be wondering if it’s as necessary for 13.1 as it is for 26.2. Honestly, I think it can’t hurt. A carb-load prior to a half-marathon needn’t last as long or be as intense, but it is still important and will have a positive impact on your race performance. Technically speaking, carb-loading really comes into play any time you are out on the road for more than 90 minutes. Carb-loading tends to lead to a bit of stiffness (because your muscles are fully stocked with glycogen) and weight gain (water retention), so for shorter events it’s really not recommended.
Since most of us take longer than 90 minutes to complete a half-marathon, my recommendation is that you carb-load in the days prior to the race. You can carb-load in as little as one day, but to prevent carb fatigue and the worry of “Am I taking in enough?” aim to start two to three days before the half-marathon. You don’t necessarily need to increase your calories—just make sure the majority of those calories come from carbs, especially at lunch and dinner the day before race day. Given time, your body can digest, absorb, and store the nutrients, and you’ll be able to rely on those fuel stores on the next day’s run. The day before race day, have your main meal at midday and a smaller meal for dinner so you have plenty of time to digest.
The pre-race meal is also very important, as you want to toe the starting line with a tank that’s primed but neither empty nor overflowing. For more ideas on what to consume pre-race, check out this past lesson on how to fuel for an early morning run
(since most races are held in the early a.m. hours).
Now that we’ve covered carb-loading and what to eat before the race, it’s time to tackle your final question: “How do I avoid running on empty in those last few miles of the race?” As you may have noticed during your training, when you’re on the road for fewer than 75 minutes, you can usually rely on water, sports drinks, and your body’s own glycogen stores to carry you along. Any longer, and you begin to deplete those stores. Your muscles run out of fuel, and your body — not to mention your attitude — starts to drag. Consuming carbs mid-run can keep your blood sugar steady, so you don’t crash and burn.
Instead of recommending something new on race day, here are some common techniques for fueling which should help you blow by that late-race wall. Since every runner is different, you may want to try one or more of the following tips during training. Maybe all of them will work, and you’ll have plenty of options to thwart the feelings of weakness in those last few miles!
Tip #1: Make sure to take in adequate fuel the day before your long run. While you are at rest, your body will have adequate time and energy to absorb and store those nutrients you ate, and then you’ll be able to rely on this fuel for the following day. And don’t forget to eat a carb-rich, low-fiber, easy-to-digest, familiar breakfast the morning of the race!
Tip #2: Fuel at regular intervals and before you need to. Wait until you’re out of gas, and you won’t be able to recover from feeling hungry or weak. Your muscles will be forced to play catch-up, and you won’t be able to bounce back and finish the run feeling strong. If you’ve ever had a long run that started strong and then got slower and slower, it may be time to consider what you did during the first few miles of the long runs that you didn’t do during the last few miles. Many runners head out the door with a full tank but, feeling great, they neglect to re-fuel over the next few miles. If you don’t start fueling within that first hour, it’s likely that your empty-tank will catch up with you, and you’ll bonk. Not only will you hit the wall, but once your muscle glycogen stores are depleted, it can be very difficult to adequately recover during your run (and you may have to walk or crawl the last few miles). My advice to avoid this whole mess? Aim for 30-60 grams of carb per hour (and start using your chews, gels, or sports drinks early and often).
#3: Don’t be afraid of fuel
. Maybe you’ve tried a product in the past and didn’t care for it or it didn’t sit well with you. If that’s the case, know that there are always new products coming out. Try a variety of products and brands. For ideas on the many different fuel options available, check out this post on energy gels
and this post on alternatives to energy gels
. Don’t be afraid to experiment with a few different products and see what works for you. Whatever concentrated form of fuel you are taking in, remember to dilute it with adequate water (or else it won’t be absorbed, and you will get nauseous). Lastly, find out what gel/product your race will be handing out. If you can tolerate or like the brand that the race is handing out, you’ll know that you won’t need to pack your own on race day. But if their chosen brand doesn’t work for you, you’ll need to plan ahead. In addition, you might try to find out at what miles the race will be handing out product and mimic that in your training to practice for race day.
Best of luck this weekend! I’ll be thinking of you and other readers as I tackle my own 13.1-mile challenge!”