Half Marathon Fueling Strategy: Why and How You Need to Fuel

The half marathon is a tricky distance when it comes to fueling. You absolutely need fuel, but how much, what type and how often depends on a number of factors; like the amount of time you’ve been running long distances or how fast you can complete the race.Having a good half marathon fueling strategy could be the final piece to hitting your next PR. I’ve seen this in so many athletes that we’ve coached over the last 10+ years. It’s the thing that helps to put your training to work.

So let’s break down some half marathon fueling questions and strategies to make it easier for us all, shall we?

Do I Need to Fuel During a Half Marathon?

Yes.

Almost universally this is the answer. As always there might be exceptions, so let’s go through some:

• If you’ll finish under 90 minutes: short carb load and pre run fuel might be enough 
• BUT many of these top finishers report they still feel stronger by fueling before mid-way for that finish kicking
• First half marathon absolutely you need to fuel
• Over 90 minutes absolutely going to benefit from topping up glycogen

Your body relies on two primary sources of fuel to feed the muscles during long runs fat and carbohydrates.

We can typically store about 90 minutes worth of glycogen stores (aka carbohydrates) in our muscles before it begins to deplete. Since most of us will take longer, there’s going to be a pay off for a smart race day fueling strategy.

During the half marathon taper, your body is going to build back up it’s glycogen stores from recovery and carbo loading. And this is crucial for your best race day performance! You need carbs.

Specifically when running at faster paces (or harder efforts), your body will switch to mostly carbs to fuel your muscles. And in a race, you want the absolute easiest and quickest form of energy available, which means taking in carbs.

When To Eat During a Half Marathon?

Step one is to ensure you’ve eaten enough prior to the race, which is covered in depth in what to eat before a race!

The most important part of half marathon nutrition is getting those calories before you actually need them. If you’re feeling low energy or have already bonked, then it’s too late and your performance will suffer.

What’s interesting is it’s less about the calories and more about telling your brain that fuel is coming! Some studies have shown even that bit of sweetness on your tongue from a sports drink can give you a boost. Photo from @sandinypaver getting ready for an ultra.

• Eat your breakfast
• Take in a little bit of carbs at the start line (Honeystinger waffle, some chews, whatever sits well)
• Take your first gel around 30 minutes – remember that it takes time for that sugar to get into the bloodstream
• Continue every 30-40 minutes after that. (See below for gram recommendations which influences timing)
• Try and time your intake with the aid station so you can wash a gel down with water (not sports drink, that’ll be sugar overload).
• It’s crucial that you hydrate!!! This is part of what helps your stomach handle gels.

Knowing when to fuel during a half marathon takes practice and requires remembering that you can’t wait until you’re feeling fatigue to fuel. You need to stay ahead of it.

Sample Half Marathon Fueling Plan

This is something we should all be practicing on long runs, that will help train your gut to be ready on race dayl.

• Start line pre-workout and or a gel
• Sipping hydration every mile or at most water stops (without hydration gels can make you feel sick and hydration is part of your fueling plan)
• 30 minutes first energy gel  (trying to hit 45-60 grams each hour)
• 60 minutes second energy gel or energy chews (I like something with a little caffeine, reminder caffeine will peak 45 minutes after you take it)
• Remember you can get carbs from your hydration too, making that 45-60 grams easier! Know what sports drink is on the course or carry your own liquid nutrition (ideas below)
• 90 minutes little bit more fuel
• Mile 11 final fuel if it’s after 90 minutes

If that feels like a lot to you, it’s because most of us have not been fueling enough. But once you start hitting these numbers, you’ll be shocked how much better the race feels. 

Of course this is highly dependent on a lot of factors. But remember that we want to be taking in 45-60 grams of carbohydrates per hour.

If you take 1 gel that’s 25 grams at 30 minutes, you need to take in another gel that same hour to hit your goal.

**Hilly races can be an exception because the higher your HR is shooting up, the more carbohydrates your body is burning. In those cases, I’ll actually organize my fueling around taking something a little before any of the major hills.

Remember if you eat breakfast two hours before even starting, you  WILL benefit from quick carbs on the start line. You want your body to feel primed to go.As always it’s key to find what works for you. Though you may not think you need a ton of fuel on your training runs, try out just one or two things to see what your stomach does. Additionally fueling those long runs is going to improve your recovery, which means better training all around.

Maybe you feel good with gels or maybe they give you an immediate stomach ache. Maybe you have a huge boost from caffeine or maybe it just makes you need to pee (and thus need caffeine free energy)!

And of course remember to practice during hard workouts too! While chews might be great on your nice easy long run, at goal pace suddenly chewing feels like a monumental effort.

What to Eat During a Half Marathon

As the understanding of sports nutrition has evolved and improved, there are now infinite options available for fueling your body during long runs.

How do you even go about sorting through all the choices? For most, it’s trial and error. The right nutrition plan is the one that works for you and doesn’t give you an upset stomach.

While some prefer gels, others go with chews or whole foods. Just remember that using whole foods means a high volume of food to hit your carb targets and that’s harder than we think. I’m a HUGE fan of using liquid nutrition options like Tailwind to hit your numbers.

Natural Energy Gels for a Half Marathon

Your half marathon fueling strategy needs to start during training!! Go to a running store and buy individual packets to test out things, then you can buy a larger pack when you know what feels good.

You might also find that having a few different types works best. This could be due to palate fatigue or because it’s slightly different carb sources.

A few energy gel favorites (of mine and those I polled) include:

• Honey Stinger
• Huma Chia Gel – the texture is a no go for me, but many of you love it
• UnTapped Maple Syrup Athletic Fuel
• Skratch Chews and hydration (Get 20% off with this link, these are a staple for me)

Easier on the Stomach Energy Options

Chews are a great alternative for those who can’t stomach energy gels. Just keep in mind that you’ll need to practice chewing something gummy while running.

It’s not as easy as you think and 1 blok or a couple beans are not the same volume of energy as a gel (which is ideal for some, but not all!).

Practice what it feels like to chew a lot while you are doing a speed workout to know if this is a good option for you.

A few of my go to picks are:

• Honey Stinger Energy Chews + Waffles
• CLIF BLOKS
• Jelly Belly Sport Beans
• Skratch Energy Drink Mix (using hydration to get in your carbs)
• Tailwind Endurance Fuel
• Gnarly Fuel2o
• UCAN – the flavor was off for  me, but it’s one that works well for many

Whole Food Running Fuels

If all the sugars in gels and chews makes your stomach revolt, whole foods might be a better option.

BUT remember that with whole foods you often need a larger quantity to hit your carb goal!

So you may need to eat more frequently to hit 45-60 grams per hour.  Cyclists can get away with more whole foods because their stomachs aren’t being jostled around and ultra runners because of the lower pace and periods hiking.

• Squeeze packet of fruit puree
• Dried apricots
• Raisins (takes an entire small box to get your carbs, per hour…not that easy while racing)
• Energy bites (here are 21 easy and delicious recipes to make your own)

I’ve got an entire post on what you need to know about using whole foods for fuel, so go read that for all the details and lot more ideas!!

Are Sports Drinks Enough for Half Marathon Nutrition?

Maybe. Like gels, chews, and whole foods, sports drinks replace some of the lost glycogen stores.

In addition, the electrolytes contained in the sodium and potassium help with fluid retention lost from sweating.

If you plan to rely solely on sports drinks as your half marathon fueling strategy, then pick one with more carbs and calories. This is NOT The time to skimp on carbs or go sugar free. (I.e. the Skratch High Carb or Tailwind noted above).

One  regular Nuun tablet contains just 10 calories and 1 gram of carbohydrates. While it’s great for some flavor, it’s not the best choice for fuel.

You also need sodium to help the gut handle all of the sugars.

Without replacing sodium during your race, you could end up:

• Muscle cramps
• Fatigue
• Hitting the Wall
• Unable to take in enough fuel
• Lightheaded

Regardless, hydration is part of fueling and should be incorporated into your training and racing nutrition plans.

What about Caffeine on Race Day?

Half marathon fueling is often not just about the carbs, but that extra energy boost.

Many energy gels and chews include caffeine for an extra boost during a long run. If you’re not a regular consumer, then don’t just go all out on race day. That could be a recipe for disaster.

Instead, experiment with one gel or chew per hour and see how your body takes it.

Or try consuming a cup of coffee in the morning 30 minutes or so before heading out on a long run, as caffeine can take 45 minutes to peak in your system.

Be sure to pay attention to how coffee affects your GI system. Does it make you need to run to the bathroom immediately, or does it take a little while to work its way through? Make sure you know the answer before leaving for that long run.

If you’re a regular coffee drinker, you can get a bigger caffeine boost by giving it up completely for 3 weeks prior to the race. It will feel like rocket fuel that day. In fact, that’s why I like to use it on race day. I rarely have caffeine, so it’s a great energy tool for me.

Need more half marathon tips?

• Half marathon pace chart
• What to wear for a half marathon
• 16 Week Half Marathon Training Plan
• How to Transition from the 10K to Half
• What To Do The Day Before a Half Marathon

Photo from the lovely @jbirdruns