---
title: "How to Avoid Hitting the Wall in a Marathon (Fuel Plan) | TrainPace"
description: "Avoid hitting the wall with a simple marathon fuel plan. Estimate carbs/hour, gels needed, and a timing schedule you can execute on race day."
url: https://trainpace.com/fuel/avoid-hitting-the-wall
---

# Avoid Hitting the Wall (Marathon Fuel Plan)

Avoid hitting the wall with a simple marathon fuel plan. Estimate carbs/hour, gels needed, and a timing schedule you can execute on race day.

The "wall" is usually a mix of going out too fast and running out of carbs. A steady pacing plan plus consistent carbs is your best defense.

- Carb targets and gel plan
- Simple schedule you can follow
- Works with your goal finish time

## How to reduce your risk of bonking

Create a pacing + fueling plan that keeps effort controlled and carbs consistent.

1. Choose a realistic goal: Pick a goal pace you can sustain without early surges.
2. Fuel consistently: Set a carbs/hour target and stick to a schedule.
3. Practice: Rehearse gels and pacing in long runs before race day.

## Frequently asked questions

### Is the wall only about fueling?

No. Pacing and conditioning matter a lot. But fueling is the most controllable lever on race day.

- [Make a Fuel Plan](https://trainpace.com/fuel)

## Fueling reference

**Race-day carb targets and gel counts by finish time (baseline, no body weight entered)**

| Race | Finish time | Carbs/hour | Total carbs | Calories | Gels |
| --- | --- | --- | --- | --- | --- |
| Half marathon | 1:20 | 45 g/hr | 60 g | 240 kcal | 2 |
| Half marathon | 1:35 | 45 g/hr | 71 g | 284 kcal | 3 |
| Half marathon | 1:50 | 45 g/hr | 83 g | 332 kcal | 3 |
| Half marathon | 2:05 | 45 g/hr | 94 g | 376 kcal | 4 |
| Half marathon | 2:20 | 45 g/hr | 105 g | 420 kcal | 4 |
| Marathon | 2:50 | 75 g/hr | 213 g | 852 kcal | 5 |
| Marathon | 3:15 | 75 g/hr | 244 g | 976 kcal | 5 |
| Marathon | 3:45 | 75 g/hr | 281 g | 1124 kcal | 6 |
| Marathon | 4:15 | 75 g/hr | 319 g | 1276 kcal | 7 |
| Marathon | 4:45 | 75 g/hr | 356 g | 1424 kcal | 7 |
| Marathon | 5:15 | 75 g/hr | 394 g | 1576 kcal | 7 |

## Other TrainPace tools

- [Pace Calculator](https://trainpace.com/calculator) — training paces from a recent race result
- [VDOT Calculator](https://trainpace.com/vdot) — fitness score and equivalent race times
- [Training Plan Builder](https://trainpace.com/plan) — week-by-week 5K to marathon plans
- [Race Fuel Planner](https://trainpace.com/fuel) — carbs per hour and gel counts
- [Elevation Finder](https://trainpace.com/elevation-finder) — GPX route and climb analysis

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- [llms.txt](https://trainpace.com/llms.txt) — site index for agents
- [llms-full.txt](https://trainpace.com/llms-full.txt) — every page's Markdown in one file
- [MCP server docs](https://trainpace.com/mcp) — endpoint, tools, and client setup