Updated: July 24th, 2013

If you run to win and are hungry for a new PR when marathon season rolls-around, then this article is for you. The competitive runner training at significant volumes and intensities requires a special approach to nutrition.

You can neither under-eat nor become too carefree with your diet if your goal is to optimize long-distance running performance.

This article is intended for those runners who are looking to maintain their weight, increase lean muscle-to-fat ratio, and perform at their best on race day.

Competitive marathoners burn through a good deal of fuel on a daily basis, but often don’t replenish their bodies adequately enough to maximize performance.

A ten mile run, no matter the pace, burns between 800-1000kcals for most runners; this is a significant expenditure of energy. If you under-fuel before and after longer runs often enough, the deficit created could sabotage your running performance and lead to injury.

For this reason, it is essential that you fuel and hydrate well prior to and immediately after running, eat a balanced diet geared towards the demands of marathon training, and support your energy needs with certain dietary supplements when needed.


If you run early in the morning, planning your nutrition can be tricky. Personally, I find it helpful to wake-up an hour prior to a morning run so I can have a light snack and cup of coffee before heading out the door. Stretching, checking emails, walking the dog, and/or doing some light strength work can also be accomplished during this time as your body gets warm after a night’s rest.

Eating something easy to digest with some decent carbohydrates at this time will help improve your performance, and having some caffeine if needed will increase mental acuity and focus. An energy bar, toaster pastry, some sports drink, or an energy gel would all do the trick; 200-400kcals is all you need to have a successful morning run after 8hrs of fasting.

If you run later in the day, or run AGAIN later in the day, be sure to prime your body for exercise with good carbohydrate intake throughout the day. Having a good breakfast and lunch containing your preferred grains, fruits, vegetables that you can digest well, and some lean protein/healthy fat will fuel you properly for an afternoon run.

Avoid eating a full meal 3-4hrs before running, but have some light snacks on hand in case you get hungry prior to running. Pretzels, crackers, energy bars, and fruit are always good choices to eat in the final hour before running if needed.

HYDRATE well all day long with water and sports drink

An often overlooked aspect of performance and injury prevention is keeping your muscles loose and supple with adequate fluids. Choose a sports drink that you like and trust to sit well before and during exercise. It should contain (at the least) moderate doses of sodium, potassium, and carbohydrates for energy.


After completing a strenuous workout, the sooner you start to replenish lost fluids and calories the better. Try to have some sports drink or water, a protein containing drink (either a commercial recovery shake or chocolate milk will do), and fruit like a banana or apple within 30min of completing your run. You can have this snack while stretch or do strength training to kill two birds with one stone.

Aside from your post-run snack, aim to have a full meal within two hours of completing your workout. This just needs to be a balanced meal containing a plenty of carbohydrates to ensure a quick recovery between training sessions.

General Nutrition

With the above fueling windows in mind, let us now look at what a day of eating/training for a competitive marathoner may look like.

Let’s assume that our hypothetical runner is training to run a marathon PR, win their age group at a large regional race, and works full time. They weigh 135lbs, and could be male or female.

How does your nutrition plan add-up?

5am- Wake-up: coffee, water, energy bar

6am- Run #1: Warm-Up, 8ml Tempo Run @ Marathon Pace, Warm-Down (11mls Total); sports drink during

8am- Breakfast: large bagel w/ cream cheese, Greek yogurt, banana; commute to work

10am- Snack: trail mix

12pm- Lunch: deli sandwich, orange juice, corn tortilla chips w/ guacamole

3pm- Snack: energy bar, sports drink

5pm (leave work) Run #2: Easy 4mls w/ Local Running Club, Core Work, Stretching; protein recovery shake and water after

7pm- Dinner: large beef stir fry with steamed rice and vegetables, salad, glass of wine

9pm- Dessert: bowl of frozen yogurt w/ berries

10pm- Bedtime

Total Calories Expended (including basal and lifestyle needs)- app. 3500kcals

Total Calorie Intake- app. 3400-3600kcals

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