What to Eat Before a Long Run: Trail Running Nutrition Guide

TL;DR

Eat carb-focused, low-fat, low-fibre food before a long run. Give yourself 2–3 hours for a proper meal, 60–90 minutes for something smaller. On race morning, eat anyway even if you're not hungry, stick to what you know, and never try anything new. The bush situation is avoidable.

A lot of us have been there. The trusty 'ol GI issue mid-run. You eat something slightly ambitious before a long run, spend the first 40 minutes quietly negotiating with your stomach, and spend the next 20 looking for a bush with enough cover.

Pre-run nutrition doesn't have to be complicated, but it does require a bit of thought. Here's what actually works.

The goal: fuel without the chaos

Before a long run, you want enough carbohydrates on board to top up your glycogen stores without eating something that's going to rebel once you start moving. Fat, fibre, and large amounts of protein all slow down digestion. At rest, that's fine. With your legs churning and your blood redirected away from your gut, it's a recipe for discomfort (or worse).

Keep it simple, carb-focused, and give it time to settle.

Timing matters more than you think

2 to 3 hours before: a proper meal works well here. Oats, toast with eggs, rice, a bagel. Something substantial but not a Sunday roast.
60 to 90 minutes before: smaller and simpler. Banana, white toast with honey, a small bowl of oats. Easy to digest, quick to absorb.
30 minutes before: if you've left it late (we've all done it), stick to something tiny. Half a banana, a few crackers. Enough to settle the 'I probably should have eaten earlier' panic.
Right before: a sip of water and the acceptance that you'll just have to fuel during the run instead.

The worst pre-run meal isn't the one that's nutritionally wrong. It's the one that sends you sprinting for the nearest tree at kilometre 3.

What to avoid

Anything high in fat or fibre right before a run is asking for trouble. Creamy sauces, big salads, full dairy, fried anything. Totally fine the night before or after. Actively unhelpful 45 minutes before a 30km effort.

Also worth mentioning: caffeine on an empty stomach hits differently when you're running. If you're a coffee-before-runs (the sport, that is) person, eat something with it. Your gut will thank you.

What about race morning?

Race morning has a special kind of stress that can kill your appetite entirely. Eat anyway. Even if it's small and bland and you have no interest in it, get something in. Aim for at least 2 hours before the start gun, stick to foods you know work for you, and resist the temptation to try that new energy or protein ,bar someone handed you at registration.

Race day is not the time to experiment. Ever. We cannot stress this enough.

Get the pre-run nutrition right and the run starts better. It really is that simple.

Frequently Asked Questions

What should I eat 2–3 hours before a long run? ▼

Something carb-focused and easy to digest — oats, toast with eggs, a bagel, rice. Substantial enough to top up your glycogen stores, but not so heavy that your stomach is still working through it when you start. Avoid anything high in fat, fibre, or protein right before a run.

What if I only have 30–60 minutes before my run? ▼

Keep it small and simple. A banana, a few crackers, or white toast with honey. Enough to take the edge off without loading your gut. If you've left it very late — under 30 minutes — have a sip of water and plan to fuel during the run instead. Don't try to make up for it with a big meal right before you head out.

What should I avoid eating before a run? ▼

Anything high in fat, fibre, or dairy right before a run is asking for trouble. Creamy sauces, big salads, fried food, full-fat dairy. All fine the night before or after — actively unhelpful 45 minutes before a 30km effort. Coffee on an empty stomach is also worth approaching carefully; eat something with it if caffeine is part of your pre-run routine.

What should I eat on race morning? ▼

Something familiar, carb-based, and eaten at least 2 hours before the start gun. Even if nerves have killed your appetite, eat anyway — something small and bland beats nothing. And absolutely do not try a new food on race morning. The energy bar someone handed you at registration stays in your pocket until after the finish line.

Does pre-run nutrition matter if I'm fuelling during the run? ▼

Yes — you start a run with whatever glycogen you've got stored from the meal before. A good pre-run meal means fuller stores at the start line and a longer buffer before you need to fuel during the run. Gels during the run top you up, but they can't fully replace a poor start. Both matter.