How to fuel for endurance training

What nutrients are important for endurance training?

Your body requires calories, nutrients, and water to function on a daily basis. When you exercise, especially when it comes to longer and more intense workouts, your needs will increase. That’s because it takes a lot of energy to get blood flowing, oxygen circulating, and muscles working for extended periods of time. 

Macronutrient timing for endurance athletes

Calories and energy comes from macronutrients. These are required in large amounts in our diets. When it comes to endurance training, eating the recommended amounts of macronutrients at specific times can help increase your stamina and success. 

Carbohydrates 

Carbohydrates are one of the most important nutrients to focus on for endurance training. Your body breaks down consumed carbohydrates into sugar, or quick energy which can be used for exercise and brain function. It’s so important that if you have extra, it goes into your bloodstream then gets transferred by your liver to be stored in your muscle as glycogen, the storage form of sugar.

The day prior to your endurance training or event, aim for a carbohydrate rich diet of at least 6 grams per kilogram of body weight and up to 7–12 grams per kilogram in the 24 hour period before the event (1). If you’re used to calculating your weight in pounds, simply divide your weight by 2.2 then you’ve got kilograms. Example: 140 pounds divided by 2.2 = 63.6 kg. 

During the endurance activity, aim for 30-60 grams per hour (if your activity is less than 2.5 hours) and 60-70 grams per hour (if over 2.5 hours). After the training, it's still important to keep fueled with carbohydrate foods or drinks every few hours. 

Download Lifesum to find out if you’re hitting the right macro goals for endurance training.

Protein

Protein is also a really important nutrient for training. That’s because it’s needed to help your muscles recover. It also helps repair and strengthen muscle tissue, both improving performance and preventing injuries or soreness (2). 

In general as an athlete it's recommended to have about 1.2-2.0 grams of protein per kilogram of body weight, per day. Before the endurance activity, go for 0.3 gram per kilogram a couple hours before. If exercise is intense, aim for about 0.25 gram per kilogram body weight per hour. After the endurance training, try for 0.3 gram per kilogram of body weight within 2 hours (3).

Fat

Fat is also essential for overall health and endurance training. Dietary fat plays a crucial role in joint structure, hormone production, cell health, and absorption of fat soluble vitamins (A, D, E, K) (4). It’s recommended not to go below 20% of your total calories. It can be helpful to limit fat before and during training though since it can cause stomach issues, as it takes longer to digest. 

Hydration

We all sweat at different rates which means our needs are different. On average, set a goal of about 400-800 mL/hour of activity (3). The weigh-in and weigh-out approach is also helpful for understanding how much fluids you may be losing. 

Endurance workouts also increase the loss of electrolytes (minerals such as sodium, calcium, and potassium) which are keys to many of our body functions including our heart. Learn which ones you may need here: Everything You Need To Know About Sports Drinks And Gels.

What to watch for

If you’re participating in an event, it's best to figure out what your body can handle during the training. Stomach upset is common for athletes since the blood flows to working muscles (5). If you’re experiencing stomach distress during a long training, and can slow down, do it. This helps redirect your blood flow back to your stomach. It can also help to cool your body, such as with a cold towel since this helps bring the blood flow back to your digestive system and away from your hot skin.

Remember that no nutrition or training plan works for everyone. That’s because we’re all unique and have different bodies, metabolisms, and nutrient and fluid requirements. To get more specific recommendations, download the Lifesum app.