Fueling guide
Carbs per hour: how much when running and cycling?
In sessions longer than about an hour, carbohydrate on the way helps. Up to about two and a half hours it is 30 to 60 g per hour, depending on pace. If it lasts longer, the amount rises to as much as 90 g per hour. From 60 g per hour, a mix of two sugars helps: glucose and fructose.Source 1Source 2
Grams per hour by duration and pace
The numbers come from the same fueling table as the app. Latu uses the same recommendation for running and cycling, so both tables hold the same numbers.
- Easy
- You could hold a conversation.
- Moderate
- Demanding, but still under control.
- Race
- As fast as you can hold for the whole distance.
Running
| Duration | Easy | Moderate | Race |
|---|---|---|---|
| 45 min | Water is enough | Water is enough | Water is enough |
| 1 h | 30 g/h | 45 g/h | 60 g/h |
| 1:30 h | 30 g/h | 45 g/h | 60 g/h |
| 2 h | 30 g/h | 45 g/h | 60 g/h |
| 2:30 h | 30 g/h | 45 g/h | 60 g/h |
| 3 h | 40 g/h | 60 g/h | 75 g/h |
| 4 h | 50 g/h | 70 g/h | 90 g/h |
| 5 h | 50 g/h | 70 g/h | 90 g/h |
| 6 h | 50 g/h | 70 g/h | 90 g/h |
Cycling
| Duration | Easy | Moderate | Race |
|---|---|---|---|
| 45 min | Water is enough | Water is enough | Water is enough |
| 1 h | 30 g/h | 45 g/h | 60 g/h |
| 1:30 h | 30 g/h | 45 g/h | 60 g/h |
| 2 h | 30 g/h | 45 g/h | 60 g/h |
| 2:30 h | 30 g/h | 45 g/h | 60 g/h |
| 3 h | 40 g/h | 60 g/h | 75 g/h |
| 4 h | 50 g/h | 70 g/h | 90 g/h |
| 5 h | 50 g/h | 70 g/h | 90 g/h |
| 6 h | 50 g/h | 70 g/h | 90 g/h |
Water is enough: for this duration your carbohydrate stores carry you. From 60 g per hour, a mix of glucose and fructose helps.Source 1Source 2
To convert: a typical gel has about 25 g of carbohydrate, a banana about 25 g, a bar about 40 g, a bottle of sports drink (500 ml) about 40 g. What you carry may differ, so check the pack.
When do I need carbohydrate on the way?
From about an hour. In longer sessions, carbohydrate taken during exercise improves performance. Latu plans it from 60 minutes at any pace. Below that your stores carry you, and water is enough.Source
Why two kinds of sugar?
Because your gut takes up two sugars through two different transporters. With one sugar alone it cannot keep up with larger amounts. That is why the up to 90 g per hour of long sessions come from a mix of glucose and fructose. Latu suggests the mix from 60 g per hour. The ingredients list tells you whether both are in it.Source
Why not 120 g per hour?
Some professionals take that much in races. A 2026 review considers 120 g possible for trained athletes. A second paper and the cycling world governing body’s position statement say the benefit is not yet shown. So Latu plans at most 90 g per hour. See 120 g as a ceiling nobody has to reach. Your stomach sets the limit.Source 1Source 2
How do I get my stomach used to it?
In training, not on race day. How much your stomach handles on the way can be trained. So try your fueling on long sessions and build up there to the amount you want to take in the race. If your stomach is not used to it yet, the race plan plans at most 60 g per hour.Source 1Source 2
What about drinking and salt?
That depends on your weight, the temperature and your pace, so it is not in this table. Drink so that you lose less than about 2 % of your body weight on the way. Drinking and eating work together. With your weight and the temperature, the race plan works out how much to drink per hour and how much sodium belongs in each litre.Source
For your race
The race plan works this out for your race, with a time for every portion. For example for a marathon in 3:45 or 100 km on the bike in 3:30.
For many races in 2027 we show you the Monday your training starts: Races 2027.
How hard easy, moderate and race are for you, the zones calculator works out from your threshold.
Latu is not a doctor. These numbers are a guide from sports science, not medical advice. If you have symptoms or a condition, talk to someone who knows about it first.
Sources
Every statement on this page rests on these entries. There you find the study, the level of evidence and the link.
- Carbohydrate needs in endurance sport: joint position statement of nutrition and sports medicine bodies from the USA and Canada (2016)
- Carbohydrate during long sessions: the cycling world governing body’s position statement (2026) and Jeukendrup (2010)
- Where the upper limit sits: a 2026 review and the papers that disagree with it
Fueling for every session, not just race day.
Latu works out the carbohydrate for every planned ride and run and plans your weeks up to the start. You have the last word.
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