• Amy Sotis

Are Carbohydrates Bad For You? Take a Look At Sports Nutrition Based on Science.

The following is a meal plan/fueling strategy I put together for an elite male marathoner. I am guessing you are not an elite male marathoner, however, read on for valuable information on one way to properly fuel for any athletic endurance events. This is an extremely detailed, specific diet regimen and rationale for anyone who wants to know the "why" behind sports nutrition recommendations to carb-load. This is not the only "good" way to fuel for an event - others have successfully competed with lower-carbohydrate diet plans, but for this example, science has shown that to maximize glycogen storage in muscle, sufficient carbohydrate intake is the fastest way to accomplish this and to replenish depleted glycogen levels.

Additionally, this blog post will cover the macro and micronutrients, as well as fluid intake for training and race day. The calorie recommendations are higher than the average person's needs, so if you want to adopt this plan, choose smaller portions and adjust accordingly.


Half-Marathon Runners, source: JJS Photography, Luminaries Retreat

For most people, even regular moderately active people, I would not recommend a high-carbohydrate diet. But, for someone who runs 15-20 miles a day in training, and who will likely complete a marathon in just over 2 hours, or anyone who will exercise for greater than 2 hours in one event, it is imperative! This plan will show you an idea of how a moderately high carbohydrate diet is acceptable and healthy for people who exercise regularly and need to have their muscle and liver glycogen stores replenished day after day. For someone looking to lose weight, I would modify this type of diet plan by reducing some of the simple carbohydrates and increasing protein and fat ratios. However, take note of the meal plan and the comments in the chart about what specific nutrients are in each food. Just because you eat a higher-carbohydrate diet, should not mean that its rich in chips, cookies, soda, and white bread! The following is actually a healthy high-carbohydrate diet, not one part of the SAD (Standard American Diet), laden with processed foods, refined sugar, and no-nutrient flour. Carbohydrates are not bad in and of themselves, but the type or source of your carbohydrate can make all the difference in the world to your performance, health, and weight.

The macronutrients in all foods are made up of either a Carbohydrate (4 calories per gram), a Protein (just under 4 calories per gram), or a Fat (Lipid) (9 calories per gram).

Chickpea, Grape, Red Onion Salad: Part of a healthy carbohydrate diet. Source: wix.com

The following diet analysis was prepared by Amy Sotis and may not be replicated, copied, or shared without express declaration that this is the property of Luminaries Retreat, LLC. Please feel free to share this blog post but do not copy and paste the contents of the plan without our permission first. Thank you!


The average size for an elite male marathon runner in 2011 was 5’6” tall and125 pounds (56.5 kg)1 and that will be the height/weight combination I will base particular calculations off of for my athlete example.

One research study of elite distance male runners showed the average energy expenditure in a normal training day was 3079 kcal and the carbohydrate (CHO) expenditure reached an average value of 10.0g k.g. b.w. per day.2 This is slightly lower but still in line with the basic sports medicine recommendations I will follow for my athlete for both training and race day which will plan for 3850 calories based on height, weight, and exercise output. The macronutrient breakdown for the training menu and the race-day menu will be 70% Carbohydrates, 15% protein, and 15% fat. This equals approximately 2700 calories from carbohydrates (678g), 577 calories from fat (64g), and 577 calories (144g) from protein.

Meb Keflezighi, American Marathon Champion, source: www.outsideonline.com

Macronutrients & Calories:

A high-carbohydrate diet, classified as approximately 70% of all calories ingested, enhances endurance capacity compared to a normal carbohydrate diet (50%) or a low-carbohydrate diet (10%). A baseline recommendation for an elite runner would be 10-12g. kg. b.w. per day (678 g or 2,700 calories from CHO per day) and 70% of total kcal coming from CHO in order to reduce symptoms of overreaching, prevent fatigue, and restore muscle and liver glycogen.3 70% of a 3850 calorie day would be 2,700 calories coming from carbohydrate or about 700 g (4 kcal per g). For a 125 pound man (56.5 kg), this would be within the 590 - 708 g range of CHO per day and on a 3850 calorie diet, that would be about 70% of calories from CHO (on the higher end of the range). In the training period, the athlete should regularly eat food items like potatoes, pancakes, vegetables, oatmeal, and rice, which are high in glucose particularly, avoiding a large portion of carbohydrates from fructose or sucrose or galactose (dairy). A combination of simple and complex carbohydrates is recommended normally, but on race day, consume foods/drinks high in glucose and low in fiber (to not upset the digestive track). Vegetables and fruits (during training particularly) are the best sources of carbohydrates for any athlete as they have a prevalence of almost all essential vitamins, minerals, fiber, antioxidants, phytonutrients and even a little protein.


Approximately 15% of total calories should come from protein. Consequently, the recommendation for my athlete will be 144g of protein or 577 calories from protein (15% of total calories, 144g x 4 kcal=577). Researchers have shown that ingesting protein with CHO immediately after endurance exercise can promote glycogen storage. This storage could contribute to a faster recovery and better adaptation, especially in athletes who participate in several training sessions each day and throughout the week and subsequently have short recovery periods. Ingesting 0.4g. kg. b.w. of protein immediately after training and 2 hours later is a common schedule that has been shown to be beneficial.2 This amounts to 22 g of protein each mini-meal. Good sources of protein are from lean meats, eggs, dairy products (which also contain valuable vitamins and minerals for the athlete), and beans.

Healthy High Protein Foods

source: Bigstock Images