Endurance Training Nutrition: Fueling Your Body for Performance and Recovery

by Cara Morrison

Endurance training, whether it's a marathon, open-water swim, or a long-distance cycle, requires more than just logging miles on a training plan. It is essential to be in tune with your body and support it from the inside out.

As someone currently training for a marathon, I have learned that progress comes from more than just running, but from how I care for my body before, after, and between runs. Optimizing energy, balancing hormones, and prioritizing recovery are just as crucial. Investing in your short-term performance goals will set you up for long-term health and longevity.

Fueling Your Body: Nutrition Tips for Endurance Athletes

Nutrition is key in maintaining a healthy lifestyle and pursuing an effective training plan. Not only does it fuel your workouts, but when utilized properly, it supports hormone balance, reduces inflammation, and speeds up recovery.

Building Balanced Plates for Energy and Recovery

Personally, I have found that I feel my best when building my meals around high-quality protein and healthy fats. It keeps my energy stable and helps me recover faster from intense training. However, I also like to include carbohydrates to replenish my glycogen stores for intense training days.

Protein: Choosing high-quality, whole food protein sources is necessary for optimal muscle growth and repair. Go for options like grass-fed beef, eggs, pasture-raised chicken, or Greek yogurt.

Healthy fats: Omega-3 fats are important for reducing inflammation and supporting hormone health. Sources include wild salmon, walnuts, and flaxseed.

Complex carbohydrates: I tend to focus on slower-digesting carbs and resistant starches for sustained energy such as sweet potatoes, berries, and quinoa.

Hydration: Essential for Endurance and Performance

Hydration is just as important as the food you eat; fluid balance is essential for energy and muscle function. I aim to hydrate consistently throughout the day to avoid bloating and GI distress that can come from chugging water right before exercising.

Formula for Daily Hydration:
(Body weight in lbs ÷ 2) + (32 oz per hour of exercise) = daily water goal in oz

For example, a 150 lb person training for 1 hour would aim for:
75 oz + 32 oz = 107 oz/day

Often on hot days or long runs, relying on water alone isn’t enough to stay hydrated. Adding electrolytes to your water replenishes minerals such as sodium, potassium, and chloride that are lost through sweat. This supports cellular hydration and prevents cramping.

Gut Health and Hormone Balance in Endurance Athletes

Several factors during training are heavily influenced by gut health. Dysbiosis in the gut microbiome can lead to an increased chance of infection and systemic inflammation.

To support gut health:

• Include probiotic-rich foods (e.g. kefir, kimchi, Greek yogurt)

• Add prebiotic-rich foods (e.g. garlic, asparagus, onions) to nourish beneficial gut bacteria

• Avoid gut irritants like processed foods and excessive alcohol

Your body is already under immense stress due to high-volume training—don’t add to it unnecessarily.

For Women:
Hormone balance is closely correlated with gut health. Intense training plans can cause fluctuations in estrogen and progesterone, which may affect energy and mood. Maintaining a diverse gut microbiome supports healthy and consistent hormone production.

Supplements for Endurance Training: My Essentials

I like to think of supplementation as the cherry on top—it adds the final touch to what you’ve already built through training, nutrition, and recovery. Utilizing the right supplements can aid in energy production, decrease inflammation, and increase connective tissue healing.

Here are some of the most effective options I recommend for endurance training:

Branched-Chain Amino Acids (BCAAs)
BCAAs are essential amino acids that help support muscle repair and reduce soreness after a workout.

BPC-157
This regenerative peptide helps accelerate healing of muscles, tendons, joints, and ligaments due to its anti-inflammatory effects. It’s effective for injury prevention and recovery. (Note: legality and availability of BPC-157 vary. Consult a professional.)

SpectraMin Electrolytes
Extended periods of long exercise involve heavy sweating, especially on hot days during summer. Keeping electrolytes in balance prevents muscle cramps and enhances hydration. I like to combine SpectraMin with BCAAs as my go-to pre-workout drink.

ATP 360
This supplement optimizes mitochondrial function by supporting the energy-producing capacity of cells. It helps improve endurance and reduce fatigue.

Collagen Powder
Collagen is essential for supporting connective tissues like ligaments, tendons, and skin. It promotes tissue repair and reduces inflammation from impact.

Quick Recap for Endurance Athletes

• Build meals around high-quality protein, fats, and slow carbs

• Stay hydrated consistently—don’t wait until you're thirsty

• Add electrolytes for better recovery and muscle function

• Prioritize gut health to reduce inflammation and support hormones

• Choose targeted supplements to support performance and healing

Endurance training is more than what meets the eye—running is just the tip of the iceberg. By utilizing intentional nutrition and smart supplementation, you will become more in tune with your body, feel good, and perform your best.

Take care of your body from the inside out and embrace the process, because training is the real marathon, and the race is just the reward.

Want to Go Deeper?

• Take our Symptom Survey to personalize your supplement plan

• Browse our Endurance Support Collection

• Book a 1-on-1 Functional Health Consult

About the Author
Cara Morrison is a rising junior at Penn State University’s Schreyer Honors College, pursuing a B.S. in Nutritional Sciences with a minor in Biology. She conducts undergraduate research on GLP-1 medications and supports student-athletes through her internship with Penn State Performance Nutrition. Cara recently completed a summer internship at The Morrison Center and is currently training for the Columbus Marathon, combining her passion for fitness, nutrition, and long-distance running. @carascleaneatz