Most runners want one number. Fair enough. Useful fueling usually starts one step earlier: what hourly carb target can I absorb on long runs, then repeat until race day feels ordinary?
Time on feet matters. So does training level, gut training, and how hard the week already is. A 40-minute shakeout is not a marathon build. Four quality sessions a week is not one easy jog.
If you want marathon finish-time bands, use the deeper guide: How many carbs per hour in a marathon. This piece sits before that. Choose your band, then train it. Sketch the plan with free tools, then practise it on the long run: running pace calculator · sweat rate calculator · fueling strategy.
Quick targets (start here)
| Who you are | Carb target | Notes |
|---|---|---|
| Building base / learning to finish longs | ~60 g per hour | Dual-source 2:1 helps comfort as you climb. Master this before chasing more. |
| Half or marathon blocks, high weekly load | ~90 g per hour | Needs consistent gut training. Common advanced age-group target. |
| Already gut-trained, chasing peak intakes | Up to ~120 g per hour | Possible for some. Not a default. Running impact often bottlenecks the gut; many runners land nearer 90. |
Sessions under ~45-60 minutes can skip mid-run carbs sometimes, if the prior meal and the rest of the week are sorted. If you train 4+ times a week with quality work stacked, even shorter hard sessions often need a simple plan so tomorrow does not fall apart. These are starting bands, not prescriptions. Body size, heat, intensity, and gut history all move the needle.
Three levers (not just the clock)
1. Training level
- Still learning to finish long runs: hold near 60 g/h.
- Racing a half or marathon with real weekly load: build toward 90 g/h.
- Already comfortable at 90 and chasing peak race intakes: only then test toward 120 g/h.
2. Gut training
Your stomach adapts. Jumping from "a gel when I feel flat" to 90-120 g/h on race morning is how GI days get written. On long runs, raise intake by about 10-15 g/h per week. Same product, same concentration, same flavour. More detail: gut training for endurance fueling.
3. Personal profile
- Pace and duration: pace calculator
- Fluid loss: sweat rate
- Full race sketch: fueling strategy
Australian heat, body size, and salty sweat change sodium needs next to the carb number. Read mg sodium on the label, not only carbs. See sodium needs for endurance athletes.
Why dual-source 2:1 shows up past ~60 g/h
Glucose-type carbs share one main gut pathway that saturates near ~60 g/h for many athletes. Fructose opens a second path. That is why high-carb mixes use dual-source ~2:1. It supports higher intakes. It does not replace gut training.
Science walkthrough: The science of dual-carb fueling.
Bottle-first, gels as top-up
Gels feel easy: open, swallow, go. The catch is practical. Many gels are light on sodium. Stack three for ~90 g carb and you can still be under-replaced on salt in the heat. Most also need water alongside.
For most long runs and marathon blocks, a liquid carb mix in a soft flask or bottle is cleaner. One sip can carry fuel, fluid, and sodium together. No separate gel timing for the baseline hour. No chasing water every kilometre.
Gels still work as a top-up, or when bottles are awkward. The flask (or bottle) holds the hourly baseline.
Format comparison: Carb drink mix vs energy gels.
That is the job HYDRAX CORE is built for: dual-source 2:1, about 85 g carbohydrate and ~980 mg sodium per labelled serve, in one bottle. Train with the serve you will race. Race what you practised. Shop it here: hydrax.com.au/products/hydrax-core.
Dual-carb, high-sodium endurance fuel. Built for the long run.
Shop HYDRAX COREHalf marathon and marathon (application)
- Half: many land 60-90 g/h once the effort is hard and longer than an easy hour. Beginners can start at 60 and climb only if the gut stays quiet.
- Marathon: 90 g/h is a common advanced target after gut training. Stay at 60 until longs prove you can handle more. Finish-time detail lives in the marathon carbs guide.
- Toward 120 g/h: advanced, practised athletes only. Train it for weeks. Running impact often makes the stomach the bottleneck, so many runners land nearer 90 than 120. Race day is the exam, not the first lesson. Motility detail: marathon carbs guide.
Pair pace with fuel: set the goal in the pace calculator, then match carbs to that duration.
A six-step protocol you can rehearse
- Know your band (60 vs 90 vs "not yet 120").
- Pick one primary bottle mix for 6-8 weeks (for example HYDRAX CORE).
- Practise on long runs. Raise slowly (~10-15 g/h per week).
- Cover sodium for heat (sweat rate).
- Use gels as backup or timed spikes, not a surprise stack.
- Sketch the week with fueling strategy.
Do not debut a new product on race morning. Write the hourly plan on your watch or bottle so you are not doing maths at kilometre 28.
Related reading
- How many carbs per hour in a marathon
- The science of dual-carb fueling
- Gut training for endurance fueling
- Carb drink mix vs energy gels
- Sodium needs for endurance athletes
- Endurance fuel for runners
Frequently Asked Questions
Under 45-60 minutes: carbs or not?
Optional on true easy singles. If you train four or more times a week, fuel the quality days and protect recovery even when some runs are short.
Is 60 g/h enough?
Yes for many beginners and intermediates. Master it before you chase 90.
When 90 g/h?
Advanced half and marathon blocks with a trained gut.
When 120 g/h?
Only if you are dialed in and have practised it. Not a default.
Gels only?
Possible. Watch sodium and water. A liquid mix in a flask is usually cleaner for the full hour: fuel and hydration in one carry. HYDRAX CORE is built for that bottle-first hour.
Is dual-source 2:1 required?
Strongly useful as you push past ~60 g/h toward 90+.