How I’m Supporting My Gut & Hormones During Marathon Training
I just kicked off training for the NYC Marathon and over the next 14 weeks I’ll be running with intention for optimized health and performance. As a functional dietitian, my lens is different. I’m not just focused on pace and mileage, but also on how my gut, hormones, and metabolism are responding to the increasing demands of endurance training.
Whether you're a runner or just navigating a season of higher stress or physical output, the same core principles apply: when your body is under more pressure, your foundational systems need more support. Here’s how I’m setting up a strong foundation for the weeks ahead.
1. Prioritizing Gut Health from the Start
Marathon training and racing place significant strain on the gut, triggering both acute and longer-term changes in gastrointestinal (GI) function and microbiome composition. This includes reduced blood flow to the GI tract, elevated stress hormones like cortisol, and mechanical stress that can irritate the gut lining. These physiological shifts can lead to increased gut permeability ("leaky gut"), temporary dysbiosis, and symptoms such as bloating, cramping, diarrhea, or nausea…especially when fueling, hydration, or recovery strategies are not aligned. The extent of these effects depends on many factors, including exercise intensity and duration, nutrition, electrolyte balance, and individual gut sensitivity.
To help protect my gut and minimize discomfort, I’m taking a proactive approach:
Timing meals strategically to minimize GI distress.…typically eating a meal ~2 hours before runs to allow digestion to complete.
Choosing gentle pre-run snacks like ripe bananas, applesauce, or rice cakes all paired with nuts/ nut butter.
Building microbiome diversity daily with fermented foods like kimchi and coconut yogurt, and prebiotic-rich options like cooked onions, chia seeds, and flaxseeds.
Staying intentional with hydration and electrolytes by focusing on blends with magnesium and potassium to support hydration, muscle function, and gut barrier health without excess sugar or additives.
Taking targeted supplements:
L-glutamine to help maintain gut barrier integrity and promote recovery, especially on long-run or high-intensity days.
Curcumin for its anti-inflammatory properties and muscle recovery. I’m using a form that’s 100x more bioavailable than standard curcumin to ensure better absorption.
And more based on my individual goals and test results.
I’m also keeping an eye on symptoms like stool changes, bloating, or energy dips since they’re often early signs of gut stress. As part of my proactive approach, I’m running a GI-MAP to get insight into my microbiome and digestive health, so I can better tailor my nutrition and support any imbalances.
2. Supporting Resilience Through Blood Sugar, Hormone & Adrenal Balance
Endurance training places added demand on the entire stress response system…not just our muscles. Long runs increase energy expenditure, elevate cortisol, and shift how our bodies regulate blood sugar and electrolyte balance. To support hormonal resilience, stable energy, and recovery capacity, I’m:
Eating within 30–60 minutes of my runs to replenish glycogen, support cortisol recovery, and include at least 30g of protein to jumpstart muscle repair and blood sugar balance.
Pairing carbs with protein and/ or fat to maintain steady energy throughout the day.
Fueling during long runs with ~25g of easily digestible carbs every 40 minutes to keep energy and cortisol stable. I like using Huma Plus gels.
Incorporating mineral-rich whole foods like roasted sweet potatoes, bananas, pumpkin seeds, and leafy greens to support adrenal health, electrolyte balance, and steady energy.
Tweaking pre-run fuel based on CGM data: I used to eat just a banana before early runs, thinking it was a quick, energizing option. But when I wore a CGM, I noticed it caused a sharp 60-point spike in my blood sugar… well above what’s typically considered optimal. For reference, a gentle post-meal rise is generally around 20–30 mg/dL, especially for maintaining metabolic flexibility and minimizing inflammation.
To explore better options, I first paired the banana with peanut butter. This didn’t reduce the peak spike, but it did make the rise more gradual. The biggest shift came when I flipped the order- eating a small handful of nuts before the banana. That combo kept my glucose rise under 20 mg/dL. While I didn’t feel a noticeable difference in the moment, the data (see graph below) helped me fine-tune my fueling strategy to better support blood sugar balance, hormone health, and sustainable performance.
My goal: fuel to perform without over-stressing my adrenals or hormones.
3. Emphasizing Anti-Inflammatory Nutrition
Training = micro-inflammation. That’s part of the adaptation process. But I don’t want to add more fuel to the fire with ultra-processed foods or under-recovery. I’m:
Cooking mostly at home with high quality anti-inflammatory, nutrient-dense whole foods.
Prioritizing deeply pigmented fruits, vegetables, herbs, and spices which are rich in antioxidants and polyphenols to combat oxidative stress, protect the gut lining, and support immune resilience.
Including omega-3-rich choices like chia seeds, walnuts, and high-quality omega-3 supplements to reduce exercise-induced inflammation and aid in recovery.
Incorporating mineral-rich foods like pumpkin seeds, leafy greens, and legumes to supply zinc and magnesium- key for tissue repair, immune modulation, and muscle recovery during times of physical stress.
My broader inflammation support includes sleep, breath work, daily mobility, and intentional nervous system care like epsom salt baths, sauna sessions, and intentional downtime to reduce emotional stress, promote parasympathetic balance, and lower systemic inflammation.
4. Prioritizing Hydration & Electrolytes
Hydration isn’t just about water, it’s about water plus electrolytes. Electrolytes help drive water into your cells where it’s actually needed, making them essential for true cellular hydration. I’m using a clean electrolyte blend daily to support:
Sodium and mineral loss through sweat which is especially important during long runs and warmer weather.
Adrenal resilience- the adrenals depend on adequate sodium, potassium, and magnesium to modulate the stress response and hormone output
Gut lining support- minerals like zinc and magnesium are key for maintaining the mucosal barrier and preventing "leaky gut" during physical stress.
Faster recovery, sustained energy, and reduced inflammation…all essential for consistent training.
Mineral repletion through hydration is a daily non-negotiable for me as it supports gut integrity, adrenal function, and sustainable energy output throughout training. I rotate between LMNT, Redmond Re-Lyte, and Jigsaw Pickleball Cocktail, and often mix LMNT with unsweetened coconut water for an extra potassium boost.
5. Staying In Tune With My Body
Training is a stressor but also an invitation to listen more closely. Some days I feel strong and energized. Other days, I take the cue to swap a workout for a walk or focus on recovery. I'm using both subjective cues and objective tools to track how my body is responding.
I’m keeping track of:
Sleep quality and consistency
Energy levels and motivation
Menstrual cycle shifts
Digestive patterns and regularity
HRV, sleep staging, and recovery data from my Oura Ring
This blend of intuition and data helps me course-correct early and fine-tune training and nutrition before small imbalances turn into bigger setbacks.
Final Thoughts
As I move through this marathon training cycle, I’ll be diving deeper into how I fuel, recover, and optimize performance from a functional nutrition perspective and sharing real-time insights, data, and gut-focused strategies that go beyond the typical training playbook. If you’re training too or just trying to heal your gut, balance hormones, and feel more like yourself again- join me in the journey!
Stay tuned for August’s post on blood sugar, endurance, and performance fueling where I’ll break down how to fuel smarter, train stronger, and feel better from the inside out!