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Ultra Fueling Planner

More ultras end in the stomach than in the legs. Build an hourly plan for calories, fluids, and sodium, then go train it until it is boring.

I learned this one the expensive way. My first ride at Big’s Backyard ended at 27 yards when nausea took over and the cutoff did not care. The lesson stuck: past a certain distance, races come down to stomachs and sleep as much as legs. This planner handles the arithmetic so you can put your attention into moving.

Important note: this is field craft from my own racing and coaching, not medical or dietetic advice. Needs vary enormously between athletes. Test everything in training, and involve a professional for medical conditions, heat illness history, or anything that feels beyond a plan on a page.

Set your targets

Start from the defaults, then adjust for your gut, your event, and your weather. Every number here gets tested in training first.

Most land between 200 and 300.

Heat and altitude push this up fast.

Salty sweaters run higher.

Plan caffeine cues

Save it for the back half or the dark.

2,500

Calories planned

3,000

Carry with 20% reserve

5 L

Fluids · 5 g sodium

1

Flasks per hour · 10 fills total

Saved on this device only. Field craft, not medical advice: test everything in training.

HourCaloriesFluidsSodiumCues
1250 cal(250 total)500 ml(0.5 L)500 mg(0.5 g)Gels + drink mix
2250 cal(500 total)500 ml(1 L)500 mg(1 g)Gels + drink mix
3250 cal(750 total)500 ml(1.5 L)500 mg(1.5 g)Gels + drink mix
4250 cal(1,000 total)500 ml(2 L)500 mg(2 g)Real food in the mix
5250 cal(1,250 total)500 ml(2.5 L)500 mg(2.5 g)Real food in the mix
6250 cal(1,500 total)500 ml(3 L)500 mg(3 g)Real food in the mixCaffeine window
7250 cal(1,750 total)500 ml(3.5 L)500 mg(3.5 g)Real food in the mixCaffeine window
8250 cal(2,000 total)500 ml(4 L)500 mg(4 g)Real food in the mixCaffeine window
9250 cal(2,250 total)500 ml(4.5 L)500 mg(4.5 g)Real food in the mixCaffeine window
10250 cal(2,500 total)500 ml(5 L)500 mg(5 g)Real food in the mixCaffeine window

Field Guide

Feeding the machine

The judgments behind the numbers, from six-day races, backyard worlds, and one very educational failure in Tennessee.

Why guts end more races than legs

Studies of hundred-mile fields keep finding the same two facts: nearly everyone reports gut trouble somewhere in the race, and nausea leads the list of reasons people quit, well ahead of fitness. Your stomach is an endurance organ doing its own ultra with less blood than it wants. Respect that, pace the first quarter like the digestion depends on it, because it does, and treat fueling practice as training, not logistics.

Train the gut

The gut adapts to load exactly like tendons do: progressively. Pick one long run a week and practice race fueling at race effort, starting at the low end and adding 25 to 50 calories an hour every few weeks. Practice eating while climbing, descending, and bored. Practice your exact race products until the wrappers open themselves. Keep at it until nothing about race fueling feels new.

Fluids and sodium set the ceiling

Calories do not absorb through a dehydrated gut. Fluids run the machine, sodium keeps the fluids where they belong, and heat multiplies both requirements faster than it feels like it should. My checklist rule of half a litre to a litre of carry capacity per hour between sources exists for exactly this reason. On long efforts, drink to a schedule in the heat and to thirst in the cool, and let the flask math in the summary tell your crew the refill rhythm.

When nausea hits anyway

It probably will, late and at night. The ladder that has brought me back: ease the pace two notches for twenty minutes, get cold fluids in small sips, add salt before sugar, and let the stomach restart before asking it to work again. Ginger and cola have saved better runners than me. What does not work is pushing the same pace on an empty tank and calling it grit. Slow is the move that keeps you in the race.

Put the plan where hands can hold it

Print the card, tape it where your crew will see it, and write the per-station translation into the Crew Plan Builder. Racing a backyard? A yard is an hour, so these targets drop straight into the Backyard Planner fueling column unchanged.

Common Questions

Fueling basics

The numbers are the easy half. Matching them to your gut, your race, and your history takes judgment, and that is what a Summit Session is for: ninety minutes on your plan, everything on the table, and a written debrief after.

Coaching

Fueling still feels like a gamble?

Nausea ended my first Big's. It has not ended a race of mine since. Let's build a plan your stomach can live with.