How to Eat for Your Next Marathon Training Block

Published September 24, 2025 02:19PM

It’s an all too familiar scene: You start a new training plan for your next marathon and things seem to be progressing well with your workouts. But as the mileage builds, you start to feel tired—and have trouble recovering from key workouts and long runs.

There’s a good chance you aren’t meeting your nutrition needs to support your training, and maybe you’re unsure how to make nutrition adjustments for different days of training. If you’re unsure what to eat when training for a marathon, this is where planning and a little work can come in handy.

Evaluating Your Marathon Training Nutrition

Keep these things in mind as you think about evaluating and changing up your own nutrition:

There is No One-Size-Fits-All Meal Plan

The ideas below are not meant to be prescriptive, but rather offer perspective on nutrition balance and timing.

Ideally, nutrition should change on the training day to help you recover quicker and reduce injury risk, but if you find this difficult to master due to reduced appetite, then adjustments to your eating in the days following should be made and increased to dig you out of your nutrition hole. As training increases, all macronutrient requirements (carbohydrates, fats, and protein) increase. The amount increased at meals and snacks depends on your body weight, training, and goals.

Focus on Being Intuitive—But Practical

For the most part, hunger and fullness cues should guide your own eating, but keep in mind that higher intensity or long training sessions can impact your hunger and suppress appetite. On those days you may need to be more practical when fueling.

Balance Your Macros

When building your meals, think about balance. It sounds simplistic, but it can ensure you at least have your bases covered before you adjust overall amounts of macronutrients. Ask yourself: “Do I have all of the following in my meals: carbohydrates, fats, protein, and fruits and vegetables?”

When building your snacks, balance can help, but also think about the macronutrients that you might struggle to get enough of at meals. Snacks can act as a vehicle for added nutrition and to help fill in nutrition gaps in your diet. Ask yourself: “Do I have a carb+fat, fat+protein, or protein+carb at this snack?” to help ensure you’re eating snacks that will promote optimal blood sugar balance and hormonal stability to aid in recovery.

Pre-Run Nutrition Needs

Focus on mostly low fiber carbohydrate sources and a little bit of protein (~8–10G) to keep blood sugar balanced pre-exercise. Fat should be limited to less than 10g as it is digested more slowly in the body and can lead to increased risk of gastrointestinal distress. A goal of 1–2g/kg body weight (~50–75G) of carbohydrates should be taken in before running. For more on what to eat, read advice from a sports dietitian on what to eat before a long run and what to eat before a morning run.

Post-Run Nutrition Needs

Focus on a combination of protein and simple carbohydrates to promote maximum rates of muscle protein synthesis and glycogen replenishment. Aim for 45–60g of carbohydrates and 15–20g of protein. Higher quality protein sources that are higher in branched-chain amino acids (dairy, eggs, soy) can be most helpful in aiding in recovery.

Timing is Important

Pre- and post-run nutrition should be dialed. Pre-run nutrition serves to give you enough energy to fuel your workouts, and post-run nutrition can help replace glycogen stores, stop muscle protein breakdown, and build and repair the body. Meals should be had regularly to help you get in all of your nutritional needs and to optimally spread out your macronutrients to help utilization.

Examples Days of Eating When Marathon Training

Keeping in mind all of the above, here are some examples of what to eat when marathon training based on your training load.

Easy Training Day (rest day, or up to 60 minutes of low-intensity training):

Pre-run snack: Two graham cracker sheets
Post-run meal (or Meal #1): Three-egg and spinach wrap with a banana
Meal #2: Turkey and hummus sandwich with baby carrots and an apple
Mid-day snack: One serving of trail mix that includes mixed nuts and dried fruit
Meal #3: Maple-glazed salmon filet with strawberry arugula side salad and quinoa

Moderate Training Day (61 minutes to 2 hours of low-intensity training, or less than 60 minutes of high-intensity intervals):

Pre-run snack: Granola bar and squeezable applesauce
Post-run meal: Peanut butter and jam overnight oats with fresh strawberries, banana, and two hard-boiled eggs on the side
Snack #2: Crackers and hummus
Meal #2: Curried chicken wrap (can sub in chickpeas or tofu to make it vegan) with two clementines and a serving of whole grain crackers
Meal #3: Pesto shrimp and asparagus pasta with a side salad
Pre-bedtime recovery snack: ½ size berry banana smoothie