Quick Start: Race-Week Fueling at a Glance

• Taper week (5–7 days out): carbs 4–6 g/kg/day; protein 1.6–2.2 g/kg/day; hydrate to pale-yellow urine.
• Day before race: carbs 6–8 g/kg; go low fiber, moderate protein, low fat; salt your food.
• Race morning (3–4 h pre): 2–4 g/kg carbs; if only 1–2 h, ~1 g/kg; add 200–300 ml water 20–30 min pre.
• During race: 30–60 g carbs/hour; 400–800 ml fluid/hour as conditions require; 300–700 mg sodium/hour.
• Caffeine (optional): 1–3 mg/kg 45–60 min pre; optional 0.5–1 mg/kg mid‑race.
• Recovery (0–60 min post): 1.0–1.2 g/kg carbs + 0.3 g/kg protein; replace 125–150% of fluid lost with electrolytes.

Taper Week (5–7 Days Out)

Training volume drops—nutrition supports glycogen stores, immunity, and muscle repair.

Daily Targets

• Carbohydrates: 4–6 g/kg/day (1.8–2.7 g/lb). Choose mostly familiar, easy-to-digest sources.
• Protein: 1.6–2.2 g/kg/day (0.7–1.0 g/lb), spaced across 3–5 meals.
• Fat: moderate; emphasize unsaturated fats but avoid heavy/fried meals if you’re gut‑sensitive.
• Hydration: roughly 30–35 ml/kg/day (0.5–0.6 oz/lb) plus what you drink during any short runs; urine pale yellow.
• Electrolytes: include salty foods (broth, pickles, soy sauce, salted rice/potatoes) if you’re a salty sweater.

Sample Day (taper, mid‑week)

• Breakfast: oatmeal with banana, honey, and Greek yogurt; orange juice.
• Snack: bagel with jam; small latte or dairy‑free alternative.
• Lunch: rice bowl with chicken/tofu, roasted carrots/zucchini, olive oil, soy sauce.
• Snack: pretzels and applesauce.
• Dinner: baked potato, salmon/tempeh, green beans; bread roll with butter; chocolate milk.

48–24 Hours Before the Race

Top off glycogen and calm the gut.

• Carbs: 6–8 g/kg/day (2.7–3.6 g/lb) for the final 24–36 hours. Example for 70 kg: ~420–560 g carbs/day.
• Fiber: reduce (white rice/pasta/bread, ripe fruit, tortillas, low‑fiber cereals). Skip large salads and heavy legumes.
• Protein: moderate (0.8–1.2 g/kg/day); choose lean and familiar.
• Fat: low‑to‑moderate to speed gastric emptying.
• Hydration: regular sipping; include electrolytes if humid/hot or you’re cramp‑prone.
• Avoid: new foods, heavy spice, alcohol, excessive caffeine, and sugar alcohols (xylitol, sorbitol).

Race‑Eve Dinner Template

• Plate: ~2/3 carbs + ~1/3 lean protein + small fat + salt.
• Ideas: white rice with teriyaki chicken/tofu and soy sauce; pasta with marinara and a small portion of grilled chicken; sushi rolls with extra rice (go easy on seaweed and fried rolls).
• Drink: ~500–700 ml (17–24 oz) with dinner; stop large volumes 60–90 minutes before bed.

Race Morning Fuel

Keep it simple, practiced, and low in fiber/fat.

If you have 3–4 hours before the start

• Carbs: 2–4 g/kg (0.9–1.8 g/lb). Example (70 kg): 140–280 g carbs.
• Examples: large bagel with jam + banana + sports drink; rice and eggs/tofu + applesauce + juice; pancakes with syrup + low‑fat yogurt.

If you have 1–2 hours

• Carbs: ~1 g/kg (0.45 g/lb), mostly simple carbs.
• Examples: instant oatmeal with honey; two toaster waffles with syrup; rice cake with jam + banana.

Final 20–30 minutes

• 15–25 g quick carbs (e.g., half a gel, chews, small applesauce pouch) + 200–300 ml (7–10 oz) water.
• Caffeine (optional): 1–3 mg/kg 45–60 minutes pre‑start. If sensitive, keep to the low end. Account for gels with caffeine.

Gluten‑free ideas: rice, corn tortillas, GF bagels/cereal, potatoes, applesauce. Vegan ideas: nut butter + jam bagel, oatmeal + maple syrup + soy yogurt, rice + tofu scramble.

During the Half Marathon

Most runners finish in 1.3–2.5 hours. Your targets depend on duration, intensity, and gut tolerance.

Carbohydrates

• 30–60 g/hour. Faster finishers (≤1:35): 30–45 g/hour. 1:35–2:30: 45–60 g/hour. Over 2:30: closer to 60 g/hour.
• Common options and typical carbs: gel 20–30 g; 3–4 chews 20–25 g; 500 ml sports drink 30–36 g (check label).
• Always take gels/chews with water for better absorption and fewer GI issues.

Fluids

• Approx. 400–800 ml/hour (13–27 oz/h), adjusting for heat, humidity, pace, and your sweat rate.
• Drink to thirst within your plan; use aid stations strategically. Don’t force excess fluid.

Sodium/Electrolytes

• Typical: 300–700 mg sodium/hour. Heavy/salty sweaters may need more.
• Count what’s in drinks/gels toward your total. Example: 500 ml sports drink might provide 300–500 mg sodium; many gels have 50–200 mg.

Optional mid‑race caffeine

• 0.5–1 mg/kg around 45–60 minutes (e.g., one caffeinated gel), especially for races >90 minutes.

Example timeline (goal 1:50 finish)

• 0:00: start well fueled; sip water as needed.
• 0:30–0:35: gel 1 (20–25 g carbs) + a few sips water.
• 1:00–1:05: gel 2 (20–25 g; caffeinated if desired) + water.
• Fluids: ~150–200 ml (5–7 oz) at each aid station depending on spacing and weather.

Adjusting for Heat, Hills, and Altitude

• Heat/humidity: move toward the upper end of fluids and sodium; slow early pace; pre‑cool (ice on neck, cool fluids).
• Hilly courses: slightly higher carb use; keep on‑course carb timing even if pace varies.
• Altitude: hydration and carbs become more important; avoid “chugging” water—steady small sips.

Gut Training and GI Troubleshooting

• Practice your exact race breakfast and on‑course fueling at goal intensity during long runs.
• Try a lower‑fiber day before long efforts; avoid high‑FODMAP foods if you’re sensitive (onions, large legumes, certain sweeteners).
• Take gels with water, not with concentrated sports drink.
• Use smaller, more frequent sips and bites if you’re prone to sloshing or cramps.
• Avoid NSAIDs around race time, which may irritate the gut.

Special Diets

• Vegan/vegetarian: great carb options include oats, rice, pasta, bread, fruit, potatoes, pancakes, sports drinks; protein from tofu, tempeh, soy yogurt, beans (reduce portion race‑evoe), and protein powders.
• Gluten‑free: rice, corn tortillas, potatoes, quinoa, GF oats/pasta/bagels; check gel and chew labels for gluten status.
• Dairy‑free: use lactose‑free or plant milks/yogurts; choose clear broths and dairy‑free desserts.
• Low‑FODMAP: white rice, sourdough bread, ripe bananas, oranges, maple syrup, oats, rice‑based cereals; test products in training.

After You Finish: Recovery Nutrition

• First 30–60 minutes: 1.0–1.2 g/kg carbs + 0.3 g/kg protein (about 20–30 g for many runners). Examples: chocolate milk + banana; recovery shake + pretzels; rice bowl with eggs/tofu and soy sauce.
• Fluids: replace 125–150% of body mass lost. If you lost 1 kg (2.2 lb), drink 1.25–1.5 L over the next few hours.
• Electrolytes: aim 500–700 mg sodium per liter of fluid to aid retention; include salty snacks or electrolyte tabs.
• Later meals: balanced plate with plenty of carbs, lean protein, colorful produce, and a calcium‑rich or fortified option.

How to Calculate Your Sweat Rate

1. Weigh nude/dry before a run (kg).
2. Run a known duration with measured fluid intake; towel off and weigh again.
3. Sweat loss (L) ≈ (pre‑weight − post‑weight) + fluid consumed (L) − urine (L).
4. Sweat rate = sweat loss ÷ hours.

Example: Pre 70.0 kg, post 69.2 kg after 1 hour, drank 0.5 L, no urine. Sweat loss ≈ 0.8 kg + 0.5 L = 1.3 L; sweat rate ≈ 1.3 L/h.

Build Your Personalized Plan (Example for 70 kg / 154 lb)

• Taper days: 350–420 g carbs/day; 110–150 g protein/day; hydrate to urine pale yellow.
• Race‑eve: ~500 g carbs; lean protein; low fiber; salted foods; ~2 L fluid across the day.
• Race morning (3 h pre): ~180 g carbs (e.g., large bagel with jam, banana, sports drink). 20 min pre: 20 g carbs + 250 ml water.
• During (goal 1:50): ~45 g carbs/h → 2 gels total; ~500–600 ml fluid/h; ~400–600 mg sodium/h.
• Recovery (first hour): ~70–85 g carbs + ~20 g protein; 1.25–1.5 L fluid per kg lost with electrolytes.

Checklist: What to Pack

• Race‑morning breakfast foods and drink you’ve practiced with.
• Gels/chews (one extra), electrolyte tabs or sports drink powder.
• Soft flask/bottles if not relying on aid stations.
• Caffeinated and non‑caffeinated options as planned.
• Salted snacks for after (pretzels, broth, recovery drink).

Common Mistakes to Avoid

• Trying new foods, brands, or doses on race day.
• Over‑hydrating without electrolytes (risk of hyponatremia) or under‑drinking in heat.
• Skipping carbs during the race and fading in the final 5K.
• High‑fiber, high‑fat dinner the night before.
• Too much caffeine if you’re sensitive.