Nutrition for Half Marathon Training

Set Daily Carbohydrate and Protein Targets First

Half marathon training usually runs 10 to 14 weeks, so the plate you eat on an ordinary Tuesday matters more than any single pre-run meal. Position stands from the American College of Sports Medicine and Dietitians of Canada put daily carbohydrate needs at roughly 5 to 7 g per kg of body weight for about one hour of training per day, rising to 6 to 10 g/kg when sessions stretch to one to three hours.

For a 68 kg (150 lb) runner that works out to about 340 to 480 g of carbohydrate on easy days and up to 680 g on the biggest days. Protein supports repair at 1.4 to 2.0 g/kg per day, or roughly 95 to 136 g for that same runner, spread across four or five eating occasions of 20 to 40 g each. Fat covers the rest of your energy needs, generally 20 to 35 percent of calories, favoring olive oil, nuts, seeds, avocado, and fatty fish.

Key takeaway: Daily carbohydrate and protein targets do the heavy lifting in a half marathon block; race-week fueling only tops off a tank you have already filled.

Build meals from whole foods so the numbers arrive with fiber, vitamins, and fluid attached:

• Rolled oats: 40 g dry (1/2 cup) as the base of a pre-run breakfast
• Banana: 118 g (1 medium) as a portable snack before or after runs
• White rice: 150 g cooked (1 cup) as a low-fiber dinner base
• Sweet potato: 150 g (1 medium, about 5 oz) for carbohydrate and potassium
• Whole-wheat bread: 56 g (2 slices) for toast before early starts
• Plain Greek yogurt: 170 g (3/4 cup) for protein with fluid
• Chicken breast: 100 g (3.5 oz) in recovery bowls
• Salmon: 100 g (3.5 oz) for protein and omega-3 fats
• Lentils: 100 g cooked (1/2 cup) for plant protein on easy days
• Orange: 140 g (1 medium) for vitamin C and water
• Low-fat milk: 240 mL (1 cup) after long runs

Your Training Fueling Timeline

Timing matters most on long-run days and barely at all on rest days. The table below is a repeatable template you can shift earlier or later to fit your schedule and your stomach.

Two habits matter as much as the rows themselves. First, keep pre-run meals low in fiber, fat, and concentrated protein, because all three slow gastric emptying when blood is being routed to working legs. Second, rehearse the exact foods you plan to use on race morning during training, not on race morning itself.

What to Eat Before a Run

A long run is easier when the meal before it matches the time you have. Aim for a full meal three to four hours out, a snack at one to two hours, and a small carbohydrate top-up in the final 15 to 30 minutes if needed.

• Three to four hours out: oats with milk and banana, or rice with eggs and fruit
• One to two hours out: toast with jam, a small bowl of cereal, or a banana with yogurt
• Fifteen to thirty minutes out: half a banana, a few dates, or a sports drink
• Within fifteen minutes of starting: nothing, if your stomach prefers running light

Morning runners often skip breakfast because of early alarms, then fade late in the run. A glass of milk or a banana eaten before you leave the driveway is usually enough to protect the final miles. Caffeine can help performance, but test it on training days first so you know how your gut responds.

Fueling During Long Runs

Runs longer than about 75 to 90 minutes need carbohydrate coming in, typically 30 to 60 g per hour. Start eating at the 45-minute mark rather than waiting for fatigue, because once you feel empty it is hard to catch up.

Gels, chews, and sports drinks are convenient and easy to portion. Real food works just as well for many runners: half a banana, 30 g of raisins (2 tbsp), a few dates, or a fig bar. Take gels with water rather than a sports drink to avoid a concentrated sugar load in the stomach, and avoid high-fiber or high-fat foods mid-run.

Gut training is a real adaptation. Practice the same fueling pattern on at least four or five long runs so your digestive system learns to handle carbohydrate while you are moving.

Recovery Nutrition After Long Runs

In the first 60 minutes after a long run, aim for roughly 20 to 40 g of protein and about 1.0 to 1.2 g of carbohydrate per kg of body weight. For a 68 kg runner that is about 70 to 80 g of carbohydrate, paired with a palm-sized protein portion.

Practical options include chocolate milk, Greek yogurt with fruit and granola, a rice bowl with chicken, or pasta with lentil sauce. Then eat a normal meal within two to three hours. Total daily intake still decides your adaptation, so recovery snacks support the day rather than replace it.

If you finish nauseated, start with fluids and a light carbohydrate source and add protein once your stomach settles. Sleep and the next day's easy session are also part of recovery.

Hydration and Electrolytes

Estimate your sweat rate with a simple test: weigh yourself nude before and after an hour run in similar weather. Each 0.5 kg (1 lb) lost represents roughly 500 mL (16 oz) of fluid, which tells you how much to drink per hour.

Most runners land between 400 and 800 mL (about 14 to 27 oz) per hour, adjusted for heat and sweat rate. Sodium losses vary widely, and 300 to 600 mg of sodium per hour covers many runners, delivered through an electrolyte drink, a salted snack, or a gel with added sodium.

Drinking far beyond your sweat losses is not safer; it dilutes blood sodium and can cause hyponatremia, so drink to thirst with a plan rather than forcing fluids. Pale-straw urine before a run is a reasonable, if imperfect, hydration check.