Marathon & Ultra Fueling 101: Carbs, Gels, and Gut Training Explained with Sports Dietitian Amy Goblirsch

Greenletes Podcast

Greenletes Podcast
Marathon & Ultra Fueling 101: Carbs, Gels, and Gut Training Explained with Sports Dietitian Amy Goblirsch
May 12, 2026
Natalie Rizzo, MS, RD

If you’ve ever hit the wall during a long run, this episode is your wake-up call.

I’m joined by registered dietitian and ultramarathoner Amy Goblirsch (aka The Running Dietitian) to break down exactly how runners should fuel for endurance—from marathons to ultras. We cover why so many runners underfuel, how many carbs you actually need per hour (hint: it’s probably more than you think), and how to train your gut so race-day nutrition doesn’t backfire.

Amy shares her real-world experience running everything from marathons to a 100-mile race (yes, really), plus practical strategies you can start using on your next long run—like how to space your fuel, what to eat when gels don’t work for you, and how to avoid common GI issues.

Apply to work with Natalie for 1-on-1 nutrition coaching! 

Have questions or want to request a show topic? DM us @greenletes

Check out Natalie's book 📕: Planted Performance



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