Key Nutrients for Marathon Training

Mastermind Weekend 1/16

Hey there!

I'm Tina

I’m the owner of Carrots ‘N’ Cake as well as a Certified Nutrition Coach and Functional Diagnostic Nutrition Practitioner (FDN-P). I use macros and functional nutrition to help women find balance within their diets while achieving their body composition goals.


An in-depth, 4-week reverse dieting course for women who feel like their metabolism has slowed down, think they might have hormonal imbalance and can’t lose weight no matter what they do.

Hi, guys! I recently had the opportunity to interview Elisa Zied, a registered dietitian, about optimal nutrition for marathon training, specifically what nutrients are important to fueling one’s body before and after workouts. I also asked her about her thoughts on protein powder and the best way to figure out how many calories I should consume after a long run. Her responses were really helpful, so I thought you guys might enjoy reading them too!


1. What are the key nutrients I should be focusing on during my training?

When you’re training, it’s key to focus on a variety of key nutrients. Since carbohydrate is the key fuel needed for your brain, red blood cells, and entire central nervous system as well as your muscles, it should be the main dietary focus before, during, and after workouts. About half of one’s total calorie intake should come from carbohydrate, and both casual exercisers and athletes alike should emphasize carbohydrate-rich foods like fruits, vegetables, and whole grains made without added sugars or solid fats. Getting adequate protein is also essential for muscle repair and to maintain lean muscle mass. Nutrient-rich options include lean meats, fish, low-fat or nonfat milk and yogurt and legumes (also packed with carbohydrate) to promote muscle repair and maintain lean muscle mass.

In addition to macronutrients like carbohydrate and protein, vitamins and minerals are essential during training. Unfortunately, national survey data reveals that many Americans have inadequate intakes of six essential vitamins and minerals; these include vitamins A, C, D, and E, and the minerals calcium and magnesium. Of course food is the best first source of nutrients. But it’s prudent for people, especially those who are active and exercise, to consider a complete multivitamin like Centrum that provides a combination of vitamins and minerals to help fill dietary gaps and ensure they meet recommended daily amounts for such nutrients.

2. What nutrients should I be sure to include in my diet for optimal post-workout recovery?

It’s important to emphasize carbohydrate to replace muscle glycogen (glucose stored in muscles) and promote rapid post-exercise recovery. Protein is also an important post-exercise nutrient to build and repair muscle tissue. To meet nutrient needs for health and to support physical activity/exercise, it’s important to include a wide variety of foods from all the healthy food groups e.g. fruits and vegetables, whole grains, low fat dairy foods, lean protein foods (fish/beef/poultry). Athletes and others who limit or eliminate one or more food groups or follow a specific diet to lose weight may require supplements; considering a complete multivitamin like Centrum is prudent as is discussing nutrient needs with a registered dietitian nutritionist and/or a doctor or other health professional well versed in nutrition and dietary supplements.

3. What are your macronutrient recommendations for endurance training?

Those who do endurance exercise like marathon training require more carbohydrate and protein than more casual exercisers. To meet needs for marathon training, athletes need about 6 to 10 grams per kilogram per day (2.7 to 4.5 grams per pound per day) of carbohydrate. Protein needs range from 1.2 to 1.7 grams per kilogram per day (0.5 to 0.8 grams per pound per day). Source:

4. What are your thoughts on protein powder/protein shakes for recovery?

While individual needs vary based on age and stage of life, gender, and activity level, most Americans get more than enough protein to meet if not exceed their dietary needs from food alone. Endurance athletes and those who strength train do need extra protein compared to non-athletes or more casual exercisers. . It’s also important that athletes consume enough total calories to meet their energy needs and maintain body weight to support the body’s use of protein and to enhance overall exercise performance.

5. What’s the best way to calculate how many calories I need pre- and post-workout?

Calorie needs vary based on age and stage of life, body frame, gender, and activity level. My best advice is to consume enough calories to maintain body weight if you’re at a healthy body weight. It’s important to eat enough while training to maintain body weight and health and maximize training. According to the most recent joint position paper on nutrition and athletic performance (, if weight loss is a goal it should be done during the off-season or before beginning a competitive season and involve a qualified sports dietitian. You can find a registered dietitian nutritionist in your area by contacting the Academy of Nutrition and Dietetics at

Elisa Zied, registered dietitian nutritionist and author of Younger Next Week and spokesperson for Centrum. Visit for more information and tips.



        1. @Tina: Carbs are without a doubt super important and extremely necessary for marathon training (and exercise or life in general) but I think 50% is high and could potentially take away from the benefits of the other nutrients and vitamins/minerals found in other foods (depending on your carb sources). With endurance training I find the timing of carbohydrates to be of the upmost importance so athletes have a steady source of energy and don’t “hit the wall”. I ran the Honolulu Marathon in December and I was pretty low carb – a banana and some fruit in my post-workout shake, a Larabar in the afternoon and a sweet potato or rice with dinner (+ apple sauce or sweet potato packs for my long runs). Protein and fat tends to be overlooked with athletes but has huge benefits in training your body to use those sources for fuel at appropriate times. Of course, everyone is different and a balanced approach is necessary but relying too heavily on carbs can actually have adverse effects. Just my two cents and how I coach the athletes I work with! Also, I think protein shakes are a great way to get in the extra calories you’re expending. It’s not always easy to replenish but liquid form of this nutrition makes it much more efficient and appetizing.

        2. @Tina: What Little Honey Bee said!! word to the wise Tina, most Dieticians are giving out old-school, out-dated information. They refuse to listen to otherwise as well – despite all the new research out now.

  1. Fantastic post and interview! I try to get my nutrients from real food, but I agree–protein substitutes can be great if you don’t get sufficient nutrition. Figuring out my nutritional plan had an incredible impact on my last marathon and my training–I went from breaking down (it seemed) all the time to having a pretty smooth training cycle.

  2. Agree with her take on protein shakes as I’ve never found much of a need unless I need major recovery calories while marathon training. Also like that she feels the right number of calories is what you’re eating when your weight is healthy and stable. No need to count or measure if we’re healthy and feeling well.

  3. I am running a 15k this weekend.. Any advice on what to eat before? I am always one to eat a really big breakfast but don’t want to right before I run… Thanks 🙂

  4. Well written and informative post, however it is very conservative. I also think that 50% carb, is too high. The sources of good quality fat have not been discuss.

    The best sentence in the article is this one:
    “if weight loss is a goal it should be done during the off-season or before beginning a competitive season and involve a qualified sports dietitian”
    For an endurance sport, one should loose weight BEFORE, then training for an long event like a marathon.

  5. Great post! Found her thoughts really interesting. I especially like how she emphasized nutrient dense carbs instead of the traditional “carb load” (aka pasta & pizza) that most people think is necessary for endurance training.

  6. Pingback: 2015 HALF MARATHON

Leave a Reply

Your email address will not be published. Required fields are marked *


Join the community!

Get recipes, workouts. and discounts straight to your inbox for FREE!
© 2022 Carrots ‘N’ Cake. All Rights Reserved | An Elite CafeMedia Food Publisher | Funnel Build & Design by: Maria Filipina Co.