Marathon Blog

Fuel Up for Long Runs


By Laurie Lasseter, Edward-Elmhurst Health & Fitness Centers


In my June blog post, we discussed proper nutrition for shorter runs. But now your training runs are getting longer and your body likely needs more nutritional and electrolyte support than it did before. It’s time to incorporate my top tips for fine-tuning your long run fueling to help tackle long runs like a pro:

Staying Hydrated

  1. Every day: Approximately ½ ounce of water for every pound of body weight per day (includes the liquid in food).
  2. During runs over 60 minutes: 7 to 10 ounces of a sports (glycogen + electrolyte) drink (such as Gatorade) or electrolyte-only drink (such as Powerade Zero or Nuun Active) every 10 to 20 minutes.
  3. During runs over 90 minutes: 7 to 10 ounces of a sports (glycogen + electrolyte) drink every 10 to 20 minutes.
  4. Post long-run: Replace 120-150% of fluid loss in water or 100-125% of fluid loss with a sports (glycogen + electrolyte) drink – use the fluid loss rate that you learned to measure in my June blog post.

Fueling for Top Performance

  1. Two hours before runs over 60 minutes: Eat a simple carbohydrate, low fiber, low protein snack – such as a bagel with a small amount of peanut butter. You’ll need to experiment a bit with the pre-run snack to see what works best for you and your digestive system.
  2. During runs over 60 minutes: Ingest 30-60g carbohydrates per hour via a sports drink (glycogen + electrolyte). See detailed hydration recommendations above.
  3. Within 30 minutes of a long run: Refuel with a protein and carbohydrate rich snack, such as such as a fruit and yogurt smoothie or a bagel with peanut or almond butter.
  4. Daily macronutrient balance: Strive to maintain a diet consisting of 55 percent carbohydrates (mostly vegetables, fruits and whole grains), 25 percent lean, high-quality protein and 20 percent healthy fats.
  5. Avoid digestive upset during long runs: It is best to avoid sugar, high-fiber, lactose-containing dairy and fat prior to your runs, at least until you understand how your digestive system responds to these foods. During your run, keep your tummy happy by avoiding caffeine and excess sugar (beyond sports drink recommendations).
  6. Smart caloric increase: You do need more calories per day to fuel your marathon training, but not as many as you might think. Depending on your size, your 40-mile per week marathon training program will probably allow you to eat 600 to 800 additional calories per day above what you would eat if you were not running at all. If you ran regularly before embarking on your training, the additional calories needed are even less. Make sure those added calories are in the form of lean protein and nutritious carbohydrates (including vegetables, fruits and whole grain foods). And, monitor your weight – the suggested calorie range is a guideline. Added body weight will hinder you from achieving your marathon training goals!


Laurie Lasseter


ACE Certified Personal Trainer

RRCA Certified Running Coach

Edward-Elmhurst Health & Fitness Centers