How to fuel for a half marathon - exactly what to eat the days before you race

what to eat before, during and after a half marathon

Training for a half marathon isn't just about planning out your runs over the course of several weeks. It's also about planning your nutrition and fueling plan. And that plan doesn't start on race day. You want to practice all of your nutrition and hydration strategies during your training to ensure you have a solid plan for the half marathon. Below are our best tips for the three most important aspects of fueling for your half marathon.

1. A few days before: carb-load

You might be wondering if it's as necessary for 13.1 as it is for 26.2, but in reality, 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 events shorter than 90 minutes, it's not recommended.

Related: 6 carb-loading recipes that don't include pasta 

Since most of us take longer than 90 minutes to complete a half-marathon, it's worth carb-loading 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.

2. The morning of your race: breakfast

The meal before the race is also very important, as you want to toe the starting line with a tank that's primed but neither empty nor overflowing. 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. The same goes for the day before your planned long runs. And don't forget to eat a carb-rich, low-fiber, easy-to-digest, familiar breakfast the morning of the race!

Related: Race-day breakfasts to rely on 

3. During the race: avoid running on empty 

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.

Related: How to pace yourself on race day 

Of course, don't try anything new on race day. Since every runner is different, you may want to try multiple strategies during your 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.

If you 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). Our advice: aim for 30-60 grams of carb per hour (and start using your chews, gels, or sports drinks early and often).

You also don't want to be afraid of fueling. 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. 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 the 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.

A version of this article appeared on Runner's World US