How Many Carbs Per Hour Do You Really Need?

For most endurance events, aim for 30–60 g of carbohydrate per hour for efforts of 1–2.5 hours, and 60–90 g per hour for anything longer. Some well-trained athletes now push to 100–120 g per hour, but only after deliberate gut training.

Why carbs matter

Your muscles store a limited amount of glycogen, typically enough for about 90 minutes of hard effort. Once those stores run low, pace drops and perceived effort climbs: the dreaded "bonk" or "hitting the wall". Taking in carbohydrate during exercise tops up your fuel supply and protects those stores.

A simple guide by duration

Why glucose + fructose works better

Your gut absorbs glucose through one type of transporter, which tops out at roughly 60 g per hour. Fructose uses a different pathway. Combining the two, often in a ratio around 2:1 or 1:0.8, lets you absorb more total carbohydrate with less stomach upset.

Putting it into practice

Think in small, regular doses rather than big hits. For a 75 g per hour target, that might look like:

• A 25 g gel every 20 minutes, or
• 500 ml of a 40 g carb drink plus one 35 g bar per hour, or
• A mix of drinks, chews and real food spread across the hour

Set a timer on your watch so you don't forget. Fueling late is much harder to recover from than fueling early.

Individual factors

Body size, intensity and fitness all affect how much you need and can tolerate. Heavier athletes and those working at higher intensities burn more carbohydrate. Heat can make the gut more sensitive, so you may need to lean more on drinks than solids on hot days.

The takeaway

Match your carb intake to the length and intensity of your event, use mixed carb sources for longer efforts, and practice in training. Precision Fuel & Hydration - 300gm Carb Flow Gel Original 510gm provides 300 gm of carbohydrate per serving to make hitting your target simple.