Fueling for Endurance Athletes by Taylor LaRosee

Fueling for Endurance Athletes by Taylor LaRosee

Written by Memories Over Macros Coach Taylor LaRosee (Learn more about her here)

When it starts to warm up outside and the sun starts to rise earlier and set later, you might be more inclined to get outside for your workout and partake in aerobic, endurance sports. Endurance itself is the ability to sustain a specific activity for a prolonged period. Typically, aerobic endurance activities last 30-60 minutes or greater and are performed at 70-75% max heart rate. Exercises such as running, swimming, cycling, and cross-country skiing are classified as endurance sports.

New and old endurance athletes alike can benefit from proper nutrition specific to endurance training. Although nutrition is often individualized and working one-on-one with a dietitian is most optimal for a specific fueling plan, there are basic nutrition guidelines that most endurance athletes can benefit from.

Macronutrient Intake

There are three main macronutrients: carbohydrates, protein, and fat. Carbohydrates are an endurance athlete’s best friend! The International Society of Sports Nutrition recommends daily intake of 5-8g/kg body weight per day for those who perform moderate to high intensity volume activities. Moderate to high intensity volume is classified as 2-3 hours per day, 5-6 days per week. You might be wondering, why are carbohydrates so important?

Well, when you eat a carbohydrate source like oatmeal for example, it’s broken down into glucose, and then stored as glycogen in the muscle and liver. When you participate in endurance activities your bodies preferred source of energy is glycogen, plus a little bit of fat storage. Since glycogen is the preferred source of fuel, when you complete an endurance activity you need to replenish those glycogen stores to be ready for your next workout!

Fueling for endurance activities is also dependent on a few factors:

  • The volume of the training cycle: Individual’s continually training in large volumes (think marathon training) will require more fuel and carbohydrates than an individual in a tapered state as they have a harder time maximizing glycogen stores.
  • Training intensity: The higher your heart rate the quicker you burn glycogen, i.e., hills or a tempo run will burn more glycogen than a shake-out run.
  • Timing of the workout: If you choose to workout right when you wake up, you might need additional fuel since you’ve been fasting for 7-9 hours, versus an individual working out in the evening who has a full day of eating under their belt.

Sample Meal Plans

For pre-workout nutrition, optimal ratios of macronutrients is dependent on how soon you will participating in the exercise.

  • 2-4 hours prior (balanced meal, carbohydrate + protein-focused, minimal fat)
    • Turkey sandwich on whole grain bread with mustard, hummus, veggies, or fruit
    • Oatmeal with milk, berries, banana, and a handful of nuts or seeds
    • Whole grain toast with peanut butter and banana
  • 30-60 minutes (simply carbohydrate + minimal protein, if tolerated)
    • Half a bagel with jam or jelly
    • Fig bar
    • Dried, unsweetened fruit
    • Toaster waffle with 2 tsp. pure maple syrup


Fueling For Endurance - by Taylor LaRosee

Intra-workout Nutrition

If endurance training activities exceed 75 minutes, aim for 30-69g of carbohydrates each hour after the first 75 minutes. Examples of easily digestible carbohydrate sources for intra-workout are gels, chews, fruit snacks, sports drinks, and dried fruit. Test out what works best for you and your GI system prior to a competition or race day! Having fuel during your workout avoids “bonking.”

As mentioned above, your body prefers glycogen as a source of fuel, once your glycogen is depleted your body will start utilizing fat and protein, which it is not nearly as efficient at, this switch from primarily using glycogen to using fat is when endurance athletes may feel fatigued, hungry, depleted, or sore.

For post-workout, the optimal ratio is 3-4:1 carbohydrate to protein ratio. The goal with post-workout fueling is to replenish glycogen stores and assist in recovery and repair of muscle. If you find that you are not hungry right after exercise, that is normal! During endurance training blood flow is diverted away from the GI system to the active muscles. Attempt to get something minimal in post-workout (chocolate milk contains the optimal carb to protein ratio!) and then eat a meal within at least 2 hours to maximize glycogen stores and muscle recovery.

Blog written by Memories Over Macros Coach Taylor LaRosee (learn about our team here)

Supplements to help

Here are 2 supplements we wanted to highlight that can help you with endurance and recovery! VersaCARB [link] from PEScience as well as their Amino IV [link]!

Don’t forget… use discount code: Aubrie to get 15% OFF your orders! 

From PEScience:

  • VersaCARB:
  • Ultra-Clean Carbohydrate†, Low Glycemic Index†, Fast Gastric Emptying†, Slow Digesting†, Mixes Easily | Neutral Taste, The Versatile Carbohydrate!†
  • Amino IV:  Amino IV delivers BCAAs, EAAs, electrolytes, and taurine. Since 2013 we have understood the importance of consuming EAAs alongside BCAAs, and through our careful processes have designed the flavors to be extremely refreshing and thirst quenching. Amino IV is most often used during training sessions, whether it be as a source of electrolytes, or a way to stay hydrated in place of a typical carbohydrate-loaded sports drink.