What are some examples of good food choices for a meal eaten about three hours before a marathon?

One of the most frequent questions our coaches get is, “What should I eat before my race/workout?” In reality, the answer they’re seeking has additional components. It’s not just what to eat, but how much to eat and when to eat it. All of these parameters are important. When you get it right, your pre-race meal tops up energy stores and enables a strong start without gastric distress. So, here’s how to get it right.

What to Eat: Lead with Carbohydrates

The big thing to remember is that carbohydrate is the fuel for high-intensity efforts, so if you’re racing or getting ready for an interval workout, you want to start with high carbohydrate availability. You are already carrying more than enough fat to provide energy for exercise, and protein is a fuel for recovery and adaptation but does not significantly contribute energy during exercise. Your carbohydrate tank is pretty limited, though. You can store about 400-500 grams of carbohydrate in your muscles and liver, enough for 1-3 hours of exercise, depending on intensity. Topping up these stores and ensuring adequate blood glucose levels (especially in the morning after sleep) are the main goals of your pre-workout/race meal.

“Lead with carbohydrate” doesn’t mean “eat only carbohydrate”. As I’ll explain below, the composition of your pre-race meal will depend on timing and how your body normally responds to ingesting food.

How much to eat before racing or working out

How much you eat will depend on the amount of time between your pre-race or pre-workout meal and the start of your effort. The earlier you eat, the bigger the meal. The 2016 “Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance” recommends 1-4 grams of carbohydrate per kilogram bodyweight before exercise, which we break down to 4 g/kg four hours out, reducing to 1 g/kg an hour or less before the start. (see figure).

Example: Using the stereotypical 70-kilogram(154-lb) athlete, these recommendations come out to 280 grams of CHO four hours before racing. That’s a big meal, with 1120 calories coming from CHO alone, which is why the recommendations should only serve as a starting point. In practice, athletes tend to prefer eating their last substantial meal 2-3 hours before competition, in part because the calorie intake and volume of food are less extreme.

You are trying to find a Goldilocks solution to having enough time to digest the meal yet eating enough to avoid getting hungry again too soon. If you eat too much too late, you risk GI distress from starting with a full stomach. On the other hand, if you eat too little too early, you’ll be hungry right before the start. If you have a choice, err on the side of eating too little and have a carbohydrate-rich sports drink available if you want some additional energy in the last 45 minutes before the start.

Pre-Exercise Meal Composition

The macronutrient diversity of your pre-race or pre-workout meal should be greatest when you have the most time available for digestion. If you are eating four hours before the start, you want a mixed meal containing fat, protein, and carbohydrate (including fiber and both complex and simple carbohydrates). Fat, protein, and fiber slow gastric emptying and slow digestion, which helps you feel satisfied longer. They also lessen the spike in blood glucose by slowing carbohydrate transport into the bloodstream.

As you get closer to your event, you want to start encouraging more rapid digestion, so you should start removing the impediments. First, reduce fat but keep protein in order to stave off hunger and support your body’s around the clock utilization of protein. Then reduce both fat and protein but keep a mixture of simple and complex carbohydrates. And finally, in the final hour before the start, stick with low fiber, mostly simple carbohydrates so they are out of the gut and into the bloodstream quickly.

Examples of Good Pre-Race Meals

3-4 Hours Before

• Breakfast Burrito: tortilla, potatoes, eggs, black beans (add rice to go big)
• Scramble: Potatoes, eggs, fresh vegetables, plus toast or bagel.

2-3 Hours Before

• Eggs and Rice: Similar to examples above, but simple and easy to digest.
• Whole grain waffles with nut butter, side of fruit.
• Yogurt mixed with granola or cereal, berries, and nuts. Add banana or toast with peanut butter to bump up the calories if necessary.

1-2 Hours Before

• Bagel with peanut butter or similar nut butter and a banana.
• Oatmeal with nuts and berries. Add brown sugar if you tolerate simple sugars well before hard efforts. Have 1-2 hard-boiled eggs on the side if you need some protein and fat to slow the rush of blood sugar. Here’s a good selection of ways some athletes adjust the nutrition and taste of oatmeal.
• Sports drink or smoothie and a sports bar or granola bar. If you perform better with less solid food before exercise, look for liquid carbohydrate sources and a few bites of something solid. 

Foods to Avoid

• Greasy, fatty, fried foods: A bacon cheeseburger is a lot of calories, but it’s more likely to put you to sleep than help you feel energized.
• This one is a little counterintuitive because it’s hard to ever discourage people from eating vegetables. The problem with high-volume, low caloric density foods like lettuce is that before a race or hard workout you want concentrated energy sources so you don’t have to eat as much volume. However, you can construct a salad to be more energy dense by adding seeds, avocado, hard boiled eggs, etc. It’s the giant bowl of lettuce that may be more problematic, because it makes you feel full when you have not actually consumed much energy.
• Sugar-free or diet foods. This should seem obvious because the point of pre-race and pre-workout meals is to provide energy. However, we find many athletes make choices from habit and convenience. The other problem is that many sugar-free foods use sugar alcohols (i.e. Xylitol, Sorbitol) as sweeteners. These can contribute to gastric distress, particularly when you add in the physical and psychological stress of competition.

Making Personal Adjustments

The next step is to take the starting point recommendations and adjust them to suit your personal needs. If you have a history of GI distress when you eat close to the start of events or workouts, then focus on more substantial meals 3-4 hours out and plan for smaller snacks closer to the start.

Reactive Hyperglycemia

Some athletes experience hypoglycemia (low blood sugar) soon after the start of exercise when they eat carbohydrates 30-45 minutes beforehand. The spike in blood sugar triggers the release of insulin, which lowers blood sugar by moving carbohydrate into tissues, like muscles. High insulin response can overlap with muscles using carbohydrate for fuel at the start of intense exercise. As a result, blood sugar levels can drop to the point of hypoglycemia, characterized by feeling dizzy, lightheaded, and nauseated. Researcher Asker Jeukendrup has a good article explaining reactive hypoglycemia. The takeaway is that if you are prone to reactive hypoglycemia, you can:

• adjust carbohydrate composition to include more low glycemic index foods (complex carbs)
• eat carbohydrates very close to the start (leaves no time for the overlap to develop)
• or eat carbohydrate further ahead of time (like 90 minutes).

Stress and pre-race foods

Anxiety and excitement can affect how you respond to eating. Stress can alter gastric emptying and gut motility, and GI distress can result from either speeding them up or slowing them down. Caffeine may exacerbate GI distress in these scenarios. If you struggle with pre-race jitters, the eating habits that work before training (a lower stress environment) may not work as well on race day. This is part of the reason you should schedule lower-priority competitions. They are a great opportunity to test out race-day nutrition in a higher stress environment.

Above all, getting your pre-race and pre-workout meals right takes practice. Start with the basics and then experiment with a variety of foods and combinations to see what works best for you.

By Chris Carmichael,
Founder and Head Coach of CTS

A good diet filled with the right nutrients is an essential part of any exercise routine, but it's especially important for endurance events like marathons or triathlons. Follow our tips to make sure you bound over that finish line...

The C factor - carbohydrate

'Hitting the wall' or 'bonking' is every distance runner's fear. It might sound like an old wives' tale, but it's a phenomenon that can happen to anyone, no matter how much training you've done. It occurs when the body's carbohydrate fuel tank - the body's preferred energy source during high intensity activity that is stored in the muscles and liver as glycogen - gets low and the brain and muscles show signs of fatigue. If you hit the wall during a marathon you'll know about it, every step feels like wading through treacle. You can avoid the dreaded wall by 'carb loading' before and during a run to maximise your energy stores, which means stocking up on lots of carbohydrate-rich pasta, potatoes, and certain fruits and vegetables.

The power of protein

Protein helps to rebuild muscle, so is particularly important after a long run to repair damaged tissue and stimulate the development of new tissue. Good protein foods to eat after a run include milk, cheese and yoghurt, white meats and eggs.

Be prepared

You need a different balance of nutrients at each stage of your training plan. With a few weeks to go, now's the time to try out foods and recipes to make sure they work for you.

A few weeks before

Your nutrition plan needs to kick in at least a few weeks before the big day. Experimenting with foods before and after a run and finding recipes you like is important - the last thing you need during the race is an unhappy stomach. Low GI carbohydrates such as wholegrain rice and pasta are good to introduce into your general diet at this stage as they release energy slowly and will build up your carbohydrate tank. The final week is the time for real carb-loading, so make pasta and porridge your friend. Be wary of gas-inducing carbs, however, such as broccoli, cabbage, beans or too much fruit, or it could make for an uncomfortable run!

Before long runs

A few hours before any long run, eat a meal high in low GI carbohydrates, moderate in protein and low in fat to give your body all the nutrients it needs for the next few hours. Porridge with fruits, a chicken sandwich and fruit or a bagel and peanut butter are good options.

During long runs

It's important to replenish your carbohydrate stores during runs of 90 minutes or more. The body can only store around 2,000 kcals of glycogen and after a few hours of running, your fuel tank warning light will flicker on unless you frequently top up your carb stores. High GI carbohydrate foods are best during a run as they release energy quickly. Choose specially designed sport gels and isotonic drinks, or try bananas, oranges, honey, dried fruit or gummy sweets such as jelly beans. Fuel every 45-60 minutes during a long run, with around 30-60 grams of carbohydrate (120-140 calories) per hour (e.g. a large banana, white bread honey sandwich or energy gels), and don't forget to stay hydrated with plenty of fluids and electrolytes.

After long runs

You have a window of around 30 mins when the body is primed to replenish its carbohydrate stores and soak upmuscle-repairing protein after a run. Chocolate milk is a good mix of protein and carbs, or whizz up a smoothie with lots of fruit. Drink plenty of fluids too to replace water and electrolytes lost through sweat.

Looking for some inspiration? Get recipes and training tips from our marathon meal plans.

Will you be racing in a marathon this year? Tell us your top tips for training and how you're getting on below.

Katie Hiscock is a fitness writer with diplomas in personal training and sports massage therapy. With an interest in sports nutrition, antenatal exercise and injury prevention, she works as a therapist for Brighton & Hove Albion.

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