How to Fuel a Gravel Ride
Gravel racing is not road cycling. It is not mountain biking. It sits somewhere between the two — long, unpredictable, often remote, and entirely unforgiving if you get your nutrition wrong.
Whether you are riding 50 km or lining up for a 200-mile event, the same three levers determine whether you finish strong or crawl to the line: carbohydrates, fluid, and sodium. Get them right, and you race. Get them wrong, and you stop.
Lever 1 — Carbohydrates
Your body stores roughly 90 minutes of glycogen. After that, without external fuel, performance drops sharply. This is what athletes call the bonk. It is not metaphorical. You cannot think clearly, your legs stop responding, and the race is effectively over.
The solution is simple in principle: eat enough carbohydrates per hour to keep your glycogen from running out.
Current guidelines for carbohydrate intake on the bike:
- Under 45 minutes — no additional carbohydrate needed
- 45 to 75 minutes — small amounts, or a carbohydrate mouth rinse
- 60 to 150 minutes — 30 to 60 g per hour
- 150 minutes and beyond — 90 g per hour or more
For longer, high-intensity gravel events, many experienced riders target 100 g or above per hour. Elite riders at events like Unbound Gravel regularly consume 90 to 120 g per hour.
The gut can be trained. Consuming 100 g of carbohydrate per hour in training is uncomfortable at first. Over time, the digestive system adapts. Practise your race-day fuelling in training — not just in long steady rides, but in interval sessions where intensity is high and eating feels difficult.
One practical principle used by sport scientists: decouple your fuel from your hydration. Get your carbohydrates from gels, bars, and chews. Keep fluid and sodium in your bottles. This means that if conditions change — it gets hotter, you need to drink more — your carbohydrate intake stays consistent without overloading your gut.
Lever 2 — Fluid
Sweat rate varies significantly between individuals. It is also heavily influenced by temperature, humidity, intensity, and how acclimatised you are to the heat. There is no universal answer to how much you should drink.
What the science gives us is a clear target: avoid losing more than 2 to 4% of your body mass to dehydration, as this is where performance begins to decline measurably.
A practical starting point in normal conditions is around 500 ml per hour, assuming you have arrived at the start line well hydrated. In hot or humid conditions, some athletes need 1 to 1.5 litres per hour.
The most reliable way to know your own needs is to measure your sweat rate across different conditions. Weigh yourself before and after sessions of a known duration without drinking, and calculate the difference. It does not require a laboratory.
One note specific to gravel racing: terrain makes drinking harder. Rough sections, technical descents, and race tactics all interrupt your ability to reach for a bottle. Build your hydration strategy around this reality. In longer races, many riders use hydration packs precisely for this reason — carrying more fluid without needing to handle a bottle on rough ground.
Lever 3 — Sodium
Sweat contains sodium, and how much you lose varies enormously from person to person. Research from over 31,000 sweat tests shows the average loss sits around 991 mg of sodium per litre of sweat — but individual results range from as low as 200 mg per litre to as high as 2,000 mg per litre.
This matters for gravel riding because sodium supports fluid retention, plasma volume, and muscle function. An athlete who loses 1,500 mg of sodium per litre and replaces it with plain water will eventually run into problems — cramps, fatigue, and impaired performance — regardless of how well they have fuelled on carbohydrates.
The practical approach is to use an electrolyte drink matched to how much sodium you personally lose. If you do not know your sweat sodium concentration, use observable signs: heavy white residue on your skin and kit after exercise, frequent cramping, and strong thirst are all common indicators of higher sodium losses.
For events lasting several hours, sodium intake before the race matters too. Drinking a high-sodium electrolyte drink the evening before and again 90 minutes before the start helps expand blood plasma volume and reduces the risk of starting in a dehydrated state.
The Day Before
Carbohydrate loading works. The evidence is clear. The goal is to maximise stored muscle glycogen by increasing carbohydrate intake to 8 to 12 g per kilogram of body mass per day in the final 48 hours before your event, while reducing foods high in fat and fibre.
For a 70 kg rider, that is 560 to 840 g of carbohydrate per day. Plain white rice, pasta, cereals, and bread are reliable choices. Avoid high-fat options like pizza — fat slows gastric emptying and reduces how efficiently those carbohydrates are absorbed.
Alongside your carb load, begin your sodium preload. A high-sodium electrolyte drink with your evening meal helps retain the fluid you are consuming. Repeat the process the following morning, approximately 90 minutes before the start.
Race Morning
Your liver glycogen depletes overnight. Breakfast is not optional.
Eat a carbohydrate-rich meal 1 to 4 hours before your start. The general recommendation is 1 to 4 g of carbohydrate per kilogram of body weight. For a 70 kg rider, aim for roughly 70 to 280 g, depending on how close to the start you are eating. Easy-to-digest foods — white rice, cereal, toast — are preferable to anything heavy or high in fat and fibre.
Continue your sodium preload if you have not already.
On the Bike
Plan your fuelling before you start. Know how many grams of carbohydrate you need per hour, know what products you are carrying, and know how many you need to get through each section between feed stations.
In data from gravel athlete case studies: 98% of riders use gels, 89% use energy drink mixes, 48% use chews, and 21% use bars on race day. No single format is required — what matters is hitting your targets consistently.
Carry a small buffer. Taking 10 to 15% more than your calculated need accounts for dropped bottles, missed feed stations, and longer-than-expected sections.
If you are racing in heat, check your bottles are secure. Rough terrain shakes bottles loose. An elastic band over your bottle cage is a simple fix that experienced riders use for exactly this reason.
The Summary
Gravel racing is long, unpredictable, and physically demanding. Your nutrition plan will be tested by terrain, conditions, and race dynamics. The riders who finish strong are almost never the ones who fuelled the hardest in the final week. They are the ones who built a plan, practised it in training, and executed it without improvising on race day.
Three levers. Carbohydrates, fluids, and sodium. Pull all three.