Last reviewed 28 October 2026
The short answer
| Ride length | Carbohydrate per hour | Notes |
|---|---|---|
| Under 1 hour | Not needed | Start fed; water is enough. |
| 1 to 2.5 hours | 30 to 60 g | A single carb source (glucose or maltodextrin) works. |
| 2.5 hours and longer | 60 to 90 g | Mix glucose and fructose to absorb more. |
| Multi-day ultras | 60 to 90 g while riding, plus real meals | Daily energy needs can exceed 6,000 kcal. |
These ranges follow mainstream sports-nutrition guidance, such as the American College of Sports Medicine's position on nutrition and athletic performance and Asker Jeukendrup's work on multiple transportable carbohydrates. Some professional riders now train their gut to take 100 to 120 g an hour in races. At brevet pace, intensity is lower, so many randonneurs do well at 50 to 80 g.
Why it matters more at ultra distances
Your body stores roughly 400 to 600 g of glycogen in muscle and liver, enough for a few hours of moderate riding. At 65% of FTP, a rider with a 250 W FTP burns somewhere around 600 kcal an hour, and a good share of that comes from carbohydrate. Fat supplies the rest, which is why a strong aerobic base matters, but no amount of fat adaptation lets you skip eating for 20 hours.
Under-fueling rarely shows up immediately. It appears as a gradual loss of power, a bad mood, poor decisions at controls and, on multi-day events, a deficit you never recover from. Eating on a schedule, before you are hungry, avoids most of it.
Fluid and sodium
- Fluid: roughly 400 to 800 ml an hour, more in heat. Drink to thirst, and check yourself by weighing before and after long training rides: losing more than 2 to 3% of body weight means drink more next time; gaining weight means you overdid it.
- Sodium: sweat sodium varies a lot between riders. Many land between 300 and 800 mg of sodium an hour on long hot rides; salty sweaters (white marks on your kit) may need more. Overdrinking plain water on a long, hot day without sodium risks hyponatraemia.
Train your gut
The gut adapts to carbohydrate intake like muscles adapt to training. If you jump from 30 g an hour in training to 90 g on event day, expect trouble. Instead:
- Fuel every ride over 90 minutes, and raise intake by about 10 g an hour every week or two.
- Use your long indoor rides to practise: same products, same timing, same concentrations as the event.
- Practise eating real food (rice cakes, sandwiches, bakery stops) as well as gels and drink mix. Sweet products get hard to face after 12 hours.
- Note what works and what does not. MeepMeep logs every fuel prompt you confirm alongside the ride.
A simple schedule
For a target of 75 g an hour: one 500 ml bottle with 40 g of drink mix per hour, plus a 25 to 30 g gel, bar or real-food snack every 30 to 40 minutes. Set reminders; on long rides your appetite is not a reliable guide.
MeepMeep prompts carbs, fluid and sodium on a schedule during the ride, takes one key press to log what you ate, and shows a running "ahead" or "behind" against your target. After the ride, it compares what you ate with estimated carbohydrate burn.
General guidance, not medical advice. If you have a medical condition, such as diabetes, or a history of gut problems on the bike, talk to a sports dietitian or doctor.
Questions
How many carbs per hour should I eat on a 200 km brevet?
Most riders do well with 50 to 80 g of carbohydrate an hour from the start, mixing drink, gels and real food at controls. Practise your intake on long training rides first.
Can I eat 90 g of carbs per hour?
Many riders can, if they train their gut and use a mix of glucose and fructose. Build up gradually in training rather than trying it for the first time at an event.
How much sodium do I need per hour cycling?
It depends on your sweat rate and sweat saltiness. Many riders use 300 to 800 mg per hour on long, hot rides. Heavy, salty sweaters may need more; on cool days you may need less.