The answer to what to eat before a long run is short: high-carbohydrate, low-fat, low-fibre food eaten 2–3 hours before you start. Oatmeal with banana and honey, a bagel with peanut butter, and white rice with a small portion of scrambled eggs, these cover most runners across most conditions. The goal is to top up liver glycogen (depleted overnight) and provide available blood glucose for the first kilometres, without leaving undigested food in your stomach when you set off. What you eat matters. When you eat, it matters more.

If you’re training toward a goal time, use our Pace Calculator to set your long run target pace. That pace also determines how aggressively your body depletes glycogen, and therefore how important pre-run fuelling is.

Why Pre-Run Nutrition Matters for Long Runs

Your muscles run primarily on glycogen, glucose stored in muscle tissue and the liver. An overnight fast reduces liver glycogen by roughly 50%. A long run at moderate intensity depletes muscle glycogen progressively, and once glycogen runs low, pace drops sharply. This is “hitting the wall,” not a fitness failure, a fuelling one.

For runs under 60 minutes at an easy pace, a modest pre-run snack or even fasted running is manageable for most people. For runs of 90 minutes and above, the territory of marathon and half-marathon training, pre-run nutrition is not optional. It directly affects how your long run goes, and therefore how your training adapts.

“A long training run is a stimulus. But if you go into it depleted, you’re not getting the full stimulus you’re just surviving the distance. The nutrition before is what makes the session productive.”

For a full picture of how training nutrition fits into marathon preparation, see our marathon nutrition plan. For the physiology of hydration specifically, our guide to hydration and running performance goes deeper.

Timing: When to Eat Before a Long Run

When you eat is as important as what you eat. The closer to your run, the smaller and simpler your food needs to be. Your digestive system slows significantly during running, and food that hasn’t fully cleared the stomach becomes a source of cramps, nausea, and GI distress.

Time before the run	Meal size	Best options
3 hours	Full meal	Oatmeal with banana and honey; bagel with peanut butter; white rice with eggs
2 hours	Medium meal	Banana, energy bar; rice cake with peanut butter
1–2 hours	Light snack	Half a banana, a few dates; small sports drink
30–60 minutes	Very light snack	Half a banana; a few dates; small sports drink
Under 30 minutes	Quick carbohydrate only	Energy gel; a few sips of sports drink

The 2–3 hour window is the target for most runners. It gives the stomach enough time to pass the meal through to the small intestine, blood sugar to stabilise, and insulin levels to drop back toward baseline before exertion begins.

A study by Dr. Asker Jeukendrup, published in the Journal of Sports Sciences, confirmed that consuming carbohydrates 1–4 hours before exercise improves endurance performance, with the 2–3 hour window generally producing the best outcomes for gut comfort alongside performance benefit.

Best Foods to Eat Before a Long Run

The guiding principle: carbohydrate-centred, low-fat, low fibre, familiar. All four conditions matter.

Carbohydrates — Your Primary Fuel

Carbohydrates break down into glucose, which either enters the bloodstream directly or is stored as glycogen in muscles and the liver. Pre-run carbohydrates top up these stores and ensure available blood glucose in the opening kilometres. In the long run, this is the most important macronutrient in your pre-run meal by a significant margin.

For a deeper look at which carbohydrate sources work best for training, see our best carbohydrates for runners guide.

Best carbohydrate choices before a long run:

• Oatmeal/porridge (rolled oats with water or milk)
• White or wholegrain toast
• Bagels or English muffins
• White rice
• Bananas, melon, canned peaches (low-fibre fruits)
• Pasta (if running in the afternoon with a 3-hour lead time)

Protein — Small Amounts Are Fine

A small amount of protein alongside carbohydrate adds satiety and helps maintain blood amino acid levels without meaningfully slowing digestion at moderate portions. Think one egg, a tablespoon of nut butter, or a small portion of Greek yogurt, not a full protein meal.

Best protein choices:

• Hard-boiled or scrambled eggs (small portion)
• Greek yogurt
• Peanut or almond butter (1–2 tablespoons)

Fat — Minimal Before Running

Fat slows gastric emptying the rate at which food leaves the stomach. A high-fat meal 2 hours before a run means food is still in the stomach when you start, which causes nausea and cramping. Keep fat to a minimum in pre-run meals. A thin spread of nut butter is fine; a full avocado toast with eggs is not.

Fibre — Avoid Before Running

Fibre slows digestion and stimulates bowel motility, the last thing you want mid-long run. High-fibre foods like bran cereals, raw vegetables, legumes, and whole-grain heavy bread should be saved for post-run meals. Pre-run, lean toward lower-fibre versions: white rice over brown, white bread over seeded, ripe banana over an apple.

What NOT to Eat Before a Long Run

Avoid these categories in the 2–3 hours before any significant run:

High-fat foods: Fried food, full-fat cheese, avocado in large amounts, creamy sauces, bacon, fatty meats. Fat delays gastric emptying and sits heavily during running efforts.

High-fibre foods: Beans and legumes, raw brassica vegetables (broccoli, cauliflower, cabbage), high-bran cereals, seeds. All increase GI motility and gas risk.

Spicy food: Causes heartburn and GI irritation at running intensity, particularly for runners prone to acid reflux.

Large amounts of dairy: Lactose can cause bloating and cramping during exertion in runners with any degree of lactose sensitivity, which is more common than most people realise.

Sugary junk: Candy, pastries, and high-GI sugary foods cause a rapid glucose spike followed by a crash that can hit at an inconvenient point mid-run. They also provide no useful micronutrition.

Unfamiliar food: Anything you haven’t eaten before a long run in training. This rule applies on race day absolutely, but it also applies in the week before any goal long run or tune-up race.

If You Run in the Morning (And Can’t Eat 2–3 Hours Before)

This is the most common pre-run nutrition problem for recreational runners. A 6 am run leaves no time for a proper 2–3 hour pre-meal window without waking at 3 am.

There are two practical approaches, and which one works depends on your body and the run duration:

Option 1: Small fast-digesting snack 30–45 minutes before. A ripe banana, 2–3 Medjool dates, or a small portion of oatmeal cooked the night before (reheated). These digest quickly, provide readily available glucose, and don’t sit heavily. This works for the majority of runners for long runs up to 90–120 minutes.

Option 2: Fasted long runs — with limits. Some runners regularly complete long runs of up to 90 minutes in a fasted or near-fasted state without issue, particularly if the pace is easy.

“For anything over 90 minutes, or anything with quality built into it marathon-pace segments, progression runs we always fuel. Fasted long runs are easy aerobic work only.”

If you’re a morning runner following a structured marathon training plan or half-marathon plan, the night-before meal matters more than usual. A carbohydrate-rich dinner the evening before a morning long run partially compensates for the short pre-run fuelling window.

Whichever approach you use, test it in training, not on race day.

Sample Pre-Run Meals at Every Timing Window

3 Hours Before

These are full meals that give your body adequate digestion time and solid glycogen loading:

• Oatmeal bowl: Large bowl of porridge with sliced banana, a drizzle of honey, and a glass of water or low-fat milk
• Bagel meal: One bagel with 2 tablespoons of peanut butter, a banana, and a glass of orange juice
• Rice and eggs: A bowl of white rice with two scrambled eggs and a small glass of fruit juice
• Toast and yogurt: 2–3 slices of white toast with honey, and a small pot of Greek yogurt

1–2 Hours Before

Lighter, faster-digesting options:

• Banana and a small energy bar
• Rice cake with a thin spread of peanut butter
• Small bowl of oatmeal (half portion) with honey
• Small fruit smoothie: banana, oat milk, a teaspoon of honey

30–60 Minutes Before

Small, simple, fast:

• Half a ripe banana
• 2–3 Medjool dates
• A few sips of a sports drink
• A small pot of applesauce

Under 30 Minutes

Emergency carbohydrate only:

• An energy gel with water
• A sports drink (small amount)
• A few jelly sweets (glucose-based)

What to Eat and Drink During a Long Run

Pre-run nutrition gets you to the starting line fuelled. During-run nutrition gets you through the long run, and this is where many beginner runners come unstuck.

For runs under 60 minutes, water is typically sufficient. For runs over 75–90 minutes, plan for:

• Carbohydrates: 30–60g per hour for runs up to 2.5 hours; 60–90g per hour for marathon-length efforts. Energy gels, sports drinks, chews, or real food like dates and banana pieces all work — provided you’ve tested them in training.
• Fluids and electrolytes: Sip water regularly rather than large infrequent amounts. For runs over 90 minutes in the heat, include sodium from a sports drink or electrolyte tablet.

For the full during-run hydration comparison, see our sports drinks vs electrolyte tablets guide. For race-day specific fuelling across all five phases of marathon nutrition, our marathon nutrition plan covers it comprehensively.

How to Avoid Stomach Problems During Long Runs

Poor pre-run food choices are the leading cause of GI distress in training runs. The mechanics: during hard exercise, blood flow redistributes away from the digestive system to working muscles, which dramatically slows gastric emptying and makes the stomach far more sensitive to what’s inside it.

Practical checklist:

• Eat at least 2 hours before any long run or hard session; 3 hours if you have a sensitive stomach
• Stick to familiar foods, introduce nothing new, on the morning of a long run
• Avoid high-fat, high-fibre, and spicy food in the 12 hours before a major long run
• Test your race-day breakfast on long training runs multiple times before race day
• If gels cause stomach problems, try different brands or switch to real-food alternatives. Gut tolerance to carbohydrate sources varies significantly between runners

Our full guide to avoiding stomach issues during runs covers the GI science and solutions in more detail.