How many carbs do I need per hour while cycling?

Carbohydrate needs depend on ride intensity and duration. For easy Zone 2 rides, 30-60g per hour is sufficient. For high-intensity efforts and racing, aim for 60-90g per hour, or up to 120g per hour if you have trained your gut and use a dual-source carbohydrate mix (glucose and fructose at a 1:0.8 ratio). Rides under 60 minutes generally do not require carbohydrate intake.

What should I eat before a bike ride?

Eat a carbohydrate-rich meal 2-3 hours before riding — for example, porridge with banana, toast with jam, or rice with a light protein source. Aim for 1-3g of carbs per kilogram of body weight. Avoid high-fat and high-fibre foods close to ride time as they slow digestion. If you only have 30-60 minutes, a small snack like a banana or energy bar is enough.

What is the glucose to fructose ratio for cycling nutrition?

The optimal ratio is 1:0.8 (glucose to fructose), based on Professor Asker Jeukendrup's dual-transporter research. Glucose and fructose use different intestinal transporters (SGLT1 and GLUT5), so combining them allows your gut to absorb more total carbohydrate per hour — up to 120g/hr with a trained gut versus roughly 60g/hr from glucose alone. Most modern cycling nutrition products use this ratio.

How much water should I drink while cycling?

A general guideline is 500-750ml per hour in mild conditions, increasing to 750-1000ml per hour in hot or humid weather. A more precise approach is to weigh yourself before and after a ride — each kilogram lost represents roughly 1 litre of fluid deficit. Add electrolytes (particularly sodium at 300-600mg per 500ml) to improve fluid absorption and replace sweat losses.

What is gut training for cycling and how do I do it?

Gut training is the process of gradually increasing the amount of carbohydrate you consume during exercise so your intestines adapt to absorb more. Start at 40-60g per hour and increase by 10-15g per week during training rides. Within 4-6 weeks, most cyclists can tolerate 80-100g per hour. Practice with the same products you plan to use in races. A trained gut can absorb up to 120g per hour using dual-source carbohydrates.

Do I need to eat on rides under 90 minutes?

For easy rides under 60-90 minutes, you generally do not need to eat — your muscle glycogen stores are sufficient. However, if the ride includes high-intensity intervals or you are doing multiple sessions in a day, having 30-40g of carbs per hour can help maintain performance. For races or hard group rides under 90 minutes, a carbohydrate mouth rinse or small intake can still provide a performance benefit through central nervous system signalling.

Free Tool

IN-RIDE FUELLING CALCULATOR

Personalised carb, fluid, and sodium targets calculated from your actual watts, session type, and local weather. Based on Jeukendrup, Morton, and Romijn.

RIDE DURATION (MINUTES)

SESSION TYPE

Session type determines what fraction of energy comes from carbs vs fat (Romijn et al. 1993). Combined with your watts, this gives a precise carb burn rate.

Steady aerobic riding. Mixed fat and carb oxidation.

TARGET POWER (WATTS)

Your expected average power for this session. A Z2 ride at 100W needs very different fuel than Z2 at 300W.

BODY WEIGHT (KG)

GUT TRAINING LEVEL

How practiced is your gut at absorbing carbs during exercise? This sets your absorption ceiling (Jeukendrup, 2014).