Race Fueling Calculator
Pop in your weight, your race and your projected finish time, and get the same fueling plan our coaches give their athletes: how much to carb load, how many carbs to take each hour, when to have caffeine and what to eat so your gut stays quiet.
- Bike carbs per hour
- 70-90g/h
- On the bike. Half that on the run.
- Carbs in the race
- 270-345g
- Over your bike and run
- Carbs the day before
- 600g
- For 75 kg
- Race morning caffeine
- 230mg
- 45 to 60 min before the start
Your plan, built on 75 kg. Built on an estimated bike 2:52, run 1:56 from your finish time. Add your own splits for a sharper number.
Carb load and race day
Two days before
Carbs 600 g (8 g per kg), protein 115 g, fat 60 g. About 3,400 kcal.
The day before
Carbs 600 g (8 g per kg), protein 115 g, fat 60 g. About 3,400 kcal.
Race day
Carbs 750 g (10 g per kg), including what you take during the race. Protein 150 g.
Hitting the number: eat it as mostly carbs from simple foods, spread over 5 or 6 meals and snacks. Juice, sports drink and white bread help when you run out of appetite.
In the race
- Bike: 70-90 g carbs per hour (gels, chews or a carb drink). Start in the first 20 min, then every 20 to 30 min.
- Run: 35-45 g carbs per hour, half the bike rate. About 270 to 345 g over your projected bike and run.
- Only if your gut is trained for it, 90-120 g per hour on the bike with glucose and fructose. Never try that for the first time on race day.
- Off the bike: one gel as you leave transition, then run on it.
- Drink 500-800 ml per hour, more if hot. Sodium per your sweat test.
- Practise this rate in your long sessions, so race day is never the first time you take that much.
For exactly how much to drink and how much sodium to take, use your sweat test in the Hydration Planner .
Caffeine
- Race week: cut back to one morning coffee or less for the last 7 days, so it bites on race day.
- Race morning: about 230 mg (3 mg per kg, a strong coffee or a caffeinated gel), 45 to 60 min before the start.
- On the bike: none.
- Start of the run: 100-200 mg, from caffeinated gels or the equivalent. Check the label.
- Daily limit: about 450 mg (6 mg per kg).
- Rehearse this in training and never take it for the first time on race day. Skip it if caffeine gives you palpitations, reflux or bad sleep.
Keep your gut quiet: low residue
Two days before the race and on race morning.
Skip
Nothing fatty, spicy or high in fibre: no fried food, creamy sauces, curries or chilli, no wholegrains, bran, beans, lentils, raw salads, cruciferous veg, dried fruit or nuts.
Eat
Eat white rice, white pasta, white bread, bagels, pretzels, potatoes without skin, bananas, juice, sports drink, honey, jam and low-fat yoghurt. Fibre under 15 g a day. A handful of pretzels with breakfast and in the 2 to 3 hours before the start.
How the numbers work
Carb load
Your muscles store more fuel when you eat more carbs and train less. For a 70.3, marathon or Ironman that means 8 to 10 g per kg (3.6 to 4.5 g per lb) on both of the last two days. Shorter races need less: 6 g per kg (2.7 g per lb) the day before an Olympic or half marathon, 4.5 g per kg (2 g per lb) the day before a sprint.
Carbs per hour
Under 45 minutes you need nothing. Up to 2 hours, 60 to 80 g an hour. Longer than that, 70 to 90 g. On the run, take half the bike rate: it is harder to eat while running.
Caffeine
About 3 mg per kg (1.4 mg per lb), 45 to 60 minutes before the start, sharpens you for the race. Cut back in race week so it works. In races over 3 hours, top up later when it gets hard.
Low residue
Two days before and on race morning, keep fibre, fat and spice low. Less in your gut means fewer pit stops and less chance of cramps or an upset stomach.
Nothing new on race day. Rehearse the carbs, the products and the caffeine in your long sessions first, so your gut knows what is coming.
Want a coach to plan your race day?
A Wingman coach builds your fueling into your plan, so you rehearse it in training and race day holds no surprises.
A guide, not a medical prescription. Questions? Ask Coach Stephan .