The Runner's Guide to Fueling

You might have heard the old adage, "You can't outrun a bad diet." While this is commonly associated with weight loss, the same goes for athletes trying to compete and train at their peak performance - no matter how well you train, if you are under or improperly fueled, your training will suffer. 

I won't go into a long Bill Nye-esque scientific explanation of how the body uses fuel because, let's be honest, most of you would scroll past this part anyway. But it is important to take a moment to understand where your body sources energy from before we discuss how to increase those sources. 

When we eat, the body breaks down carbohydrates into happy little glucose balls, which are then released into the blood stream.  As blood sugars rise, the pancreas releases insulin, which allows for the uptake of these glucose balls into the cells. In the presence of insulin, the cells act like a game of Hungry Hungry Hippo, grabbing up as much glucose as possible for future use (as glycogen).  

These cells (or Hippos, if you're following along) belong in the liver and the muscle tissue and are responsible for most of the glycogen that is used during most aerobic activity.  

Depending on the individual, the liver can store as much as 400 calories (100g) of carbohydrates and the muscle tissue upwards of 1200 calories (350g). 

Now this all sounds great - the body stores more than enough energy for you to burn during your standard workout (that is, less than 90 minutes).  But, this is assuming that your body is always topped off. Think of it this way - how often do you get into your car and you have a full tank of gas? Almost never? The same goes for your body.  If we are improperly fueling before and after workouts, it's the same as never having a full tank of gas. High intensity, long duration or multiple daily workouts can drain glycogen stores, even if you are eating to your daily requirements.

So how can you break this cycle and get the most out of your workouts? Simple.  Pay attention to when you eat. 

The night before

Here is your chance to go wild. And by wild, I simply mean to eat a large, carbohydrate filled meal of your choosing. However, making sure that you stay away from the high-fat pasta sauces (such as alfredo) or high-fiber foods will help prevent gastric distress in the morning. Many runners prefer to eat a dinner of pasta or pizza pre-morning workout, but you can derive the same effect from a healthy dinner of chicken, steamed broccoli and rice.  Going to bed properly hydrated is important as well, so having an additional 12-24 oz of water with dinner is helpful.

Four hours before exercise

This is for my athletes that workout after work.  If this is you, four hours could be anywhere between 12-2pm in the afternoon, which allows this carbohydrate loading time to be in perfect sync with a lunchtime meal or a post-lunch snack.  This is the ideal window to restore liver glycogen and store additional carbohydrates in the muscle for the later workout. Since you have a sizable amount of time between eating and working out, you can be a little bit more flexible with any foods that work well with your body.  Eating as a runner is highly individual, since some foods may digest better than others for some.  However, I like to make sure that there is a small amount of protein and fat in the meal as well, to protect against a large insulin spike and increase satiety. 

Depending on your body weight and size, some suitable options for carbohydrates would be a bowl of yogurt, topped with fruit (such as strawberries and bananas) and a small dab of peanut/almond/nut butter.

You could also choose to make a peanut butter sandwich topped with bananas and honey (a personal favorite!). Fruit juices or sports drinks are also a good choice if you are looking to add more carbohydrates to your system without feeling overloaded.  

Two hours before exercise 

The closer that we get to the workout, the more important it is to ingest easily absorbed carbohydrates, most likely from liquid sources. Another key factor is your stomach's own tolerance for taking in fuel so close to a workout. For some, eating too much (or the wrong kinds) of foods before a run will cause indigestion, bloating, and upset stomach.  For that reason, I suggest scaling the meal accordingly.  If you workout in the mid-morning (such as rising at 7am for a 9am workout) or in the late afternoon, post-work, an easy grab-and-go option is a fruit smoothie.  You can include a small amount of protein or fat in your smoothie, but I would caution against anything high in fiber this close to a workout.  The fiber will cause digestion to slow, potentially limiting the amount of carbohydrates that will be absorbed.

If you are in a work situation and making a smoothie is not an option, another quick option are real food bars, such as Thunderbird or RX Bars (but again, individual tolerance for food versus fluid should be acknowledged). Mostly importantly, this is a crucial time to "top off" the fuel reserves and in most cases, eating something is absolutely preferable to eating nothing.

One hour before exercise

This is for my morning runners.  I can't stress enough how important it is to get something - anything - into your body before a morning run. A full night's sleep is, simply put, an eight hour fast. Since most of us are not sleepwalking to the fridge to eat, it has been eight hours since we ate or drank anything.  Making sure to get up in the morning and eat something is crucial to being properly fueled for a long run.

Depending on the length or intensity of the workout, I like to use UCAN, which is a super starch that I have found to be gentle on the stomach while still providing a large dose of carbohydrates. You can also consider using a sports gel, such as GU or Clif, or fruit juice, immediately prior to a workout.

If you want real food, and your stomach will tolerate eating, choose fruits low in fiber (such as bananas)! 

Another pre-race nutrition add-on that I have started using is Beet Elite. There has been some recent scientific evidence lately to show that nitrate-packed beet juice enhances blood vessel dilation. This increases the blood flow capacity throughout your body and lowers the amount of oxygen that your muscles need. Simply, it could potentially extend your endurance.

During Workout

The fuel that you use during your workout/marathon/event, to me, is all personal preference. I think that there are countless options for runner nutrition, but ultimately, they are all the same. Whether you like chews, jelly beans, waffles, or gels, these bite-size nutrition blocks offer up, on average, 100-200 calories of easily digestible carbohydrate. I would highly encourage you to buy a variety of fuel and test them over the course of your training. My personal favorite is Salted Caramel Gu. On average, after the first 60 minutes, I try to take one gel (100-150 calories) every 45 minutes. This, again, is subjective to the size, stature, and efficiency of the runner in question, but is a good ballpark for those starting out.

Another option, for those inclined to carry handhelds, is Tailwind or Skratch. Both of these are liquid calories that can be carried in a water bottle and sipped on slowly during a race. I find that these are great options for training runs or trail races, but could potentially become inconvenient during a marathon. However, these options (Skratch, specifically) are gentle on the stomach if other options cause intestinal distress.

Immediately post workout

If there were to be two crucial hours in your life, I would name the two post-workout as hands-down, without a doubt, the most important. In fact, eating within 30 minutes of a workout is going to insure that you are doing your best to immediately replenish the glycogen stores that were lost during the activity. This is that key window when the muscle is the most responsive to the calories that you have lost.  

An ideal recovery ratio would look like this : 2:1 or 3:1 carbohydrate to protein. Ingesting carbohydrate insures that the glycogen stores are replenished and protein provides nutrients to muscle and stimulates growth.  A great option would be a glass of chocolate milk or a protein and fruit smoothie.  If the idea of a thick beverage turns your stomach after a run, consider the real food energy bars (Thunderbird or RX) or a turkey sandwich on a whole-grain bagel.  

Don't neglect your hydration!

As important as nutrition is in your performance, hydration plays a crucial role. You never want to start a workout dehydrated.  In order to maintain an effective level of hydration, I suggest drinking 1/2 body weight in ounces each day. This will help keep you on top of your hydration, but it's imperative that you continue to take in fluids while you exercise as well.  Consider using a handheld water bottle (I love easy-to-hold options like this one from Nathan), to insure that you are drinking while running or exercising.  Depending on your rate of sweat loss, drinking 4 to 8 ounces of water every 15 minutes (or approximately half the above listed water bottle), is suggested to maintain against too much fluid loss.  Keeping an eye on your electrolyte levels by using salt tabs, such as Salt Stick, or electrolyte replenishment solutions, such as Tailwind, are another good way to make sure that you are performing at your peak. Hydration post-workout is equally important.  I like to suggest drinking 1 ounce for every minute of exercise in the heat, making sure to add in electrolytes into your recovery plan. 

Nutrition is a crucial piece in sports performance and one that is highly individualized to the athlete. Don't neglect it! 

Interested in your own customized nutrition plan? 

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