Running on GLP-1s

Running jostles the stomach. GLP-1s slow gastric emptying. The combination means that anything you eat sits longer, and solid food can feel like a brick. That does not mean you should not fuel. It means you need to choose forms that leave the stomach fast.

For runs under 60 minutes, a small carb snack is enough — half a banana, a gel, or a few crackers. For long runs or hard workouts, aim for 30–60g carbs 90–120 minutes before. Liquid or semi-liquid carbs tolerate better than dense solids on the medication.

Start fueling early. For runs over 60 minutes, take 20–30g carbs every 20–25 minutes. Gels, chews, or liquid carbs work better than bars. Wash each down with water, not just a sip. If you wait until you feel low, you are already behind.

Runners lose fluid fast. In heat, aim for 500–750ml per hour with sodium. If you are cramping or your heart rate drifts upward for the same pace, sodium is likely too low. Use the electrolyte calculator to dial it in.

Within 30–60 minutes: 20–30g protein plus 40–60g carbs. Chocolate milk, a protein shake with fruit, or a real meal if you can tolerate it. This window is where the next week's training is won or lost.

Do not experiment. Race with the same fuel you used in training. Practice taking gels at the pace you will hold. GLP-1 stomachs do not forgive last-minute changes.