High-Carb Cycling Nutrition: How to Build from 60 to 90—and Possibly 120 g per Hour
High-carbohydrate fueling has become one of road cycling's loudest performance conversations. Ninety grams per hour is now common in long-race plans, while some professionals and well-trained amateurs experiment with 100–120 g/h. The useful lesson is not that every cyclist should immediately pour 120 grams into a bottle. It is that carbohydrate intake can be matched to ride duration, intensity, logistics and individual tolerance.
Current consensus still supports up to 90 g/h from multiple transportable carbohydrates for demanding exercise lasting more than roughly 2.5–3 hours. Research on 120 g/h is promising in trained participants, but it remains an advanced option—not a new minimum and not proof that more is always better.
This guide explains the evidence, how to calculate what is actually in your bottles and pockets, and how to practise a plan without promising a “GI-distress-free” result. Riders with diabetes, gastrointestinal disease, food allergies, disordered-eating concerns or other medical conditions should discuss major fueling changes with a qualified clinician or sports dietitian.
The Practical Targets
| Ride demand | Evidence-based starting range | Practical approach |
|---|---|---|
| Under ~60 minutes | Usually no during-ride carbohydrate required | Start fed; water as needed |
| 60–150 minutes | Roughly 30–60 g/h | Drink, gel, chews or food according to intensity |
| Over 2.5–3 hours, demanding | Up to 90 g/h | Use glucose plus fructose sources and practise beforehand |
| 100–120 g/h | Advanced, individualised trial | Consider only after tolerating 90 g/h in relevant training |
Short, easy rides do not automatically need race-level intake. Conversely, a hard four-hour gran fondo may justify more carbohydrate than a five-hour social ride with café stops. The target should support the work, not become a competition of its own.
Why Glucose and Fructose Are Combined
Glucose-based carbohydrate uses the intestinal transporter SGLT1, while fructose uses GLUT5. Combining sources can increase carbohydrate delivery and oxidation compared with relying on large amounts of glucose alone. This is the basis for modern “multiple transportable carbohydrate” products.
Older recommendations often used a 2:1 glucose-to-fructose ratio. Many current products use ratios closer to 1:0.8, which provides relatively more fructose. That ratio is a formulation choice supported by emerging work; it is not a magic shield against nausea or bloating. Total concentration, fluid intake, heat, effort, anxiety and the rider's habitual diet still matter.
At 90 g/h using a 1:0.8 glucose-to-fructose ratio, the approximate split is 50 g glucose-based carbohydrate and 40 g fructose. At 120 g/h, it is roughly 67 g and 53 g. Those calculations explain the formulation—they do not prove that every intestine can comfortably process the dose.
What the Research Says About 120 g/h
The strongest established guideline remains up to 90 g/h for prolonged, demanding exercise. A 2022 study in 11 highly trained male cyclists found higher exogenous carbohydrate oxidation at 120 versus 90 g/h, but no additional reduction in the use of endogenous carbohydrate. The authors specifically called for more work on performance outcomes.
Newer research in 16 trained cyclists and triathletes found that 120 g/h better preserved critical power after three hours of moderate cycling than 60 g/h. That is relevant evidence, but the sample was small and trained. It does not turn 120 g/h into a universal recommendation for recreational riders, women, older athletes or people with sensitive gastrointestinal systems.
A contemporary review similarly notes that athletes increasingly report 120–200 g/h, while evidence is not yet broad enough to replace consensus guidance. Another dose-response cycling study found diminishing gains above about 78 g/h in its particular 160-minute protocol. Duration, pre-ride glycogen, workload and study design differ, so there is no single number that wins every ride.
| Claim | What the evidence supports | What it does not support |
|---|---|---|
| “90 g/h is useful” | Established option for long, hard events using mixed carbohydrates | Required on every endurance ride |
| “120 g/h can be oxidised” | Demonstrated in small studies of trained participants | Guaranteed performance gain for everyone |
| “More carbohydrate spares glycogen” | Carbohydrate supports blood glucose and oxidation | Unlimited sparing at ever-higher doses |
| “Gut training helps” | Repeated practice can improve tolerance and execution | A fixed schedule that eliminates symptoms |
Build the Plan from Products, Not Marketing Names
Count grams per serving, then count servings per hour. Maurten Gel 100 contains 25 g carbohydrate. SiS Beta Fuel 80 lists 80 g in a prepared serving. Skratch Super High-Carb currently lists about 50 g per serving. Packaging and formulations can change, so verify the label you actually buy.
Example combinations are arithmetic, not prescriptions:
| Target | Example combination | Total |
|---|---|---|
| 60 g/h | 40 g drink + 20 g from food or chews | 60 g |
| 75 g/h | 50 g drink + one 25 g gel | 75 g |
| 90 g/h | 40 g drink + two 25 g gels | 90 g |
| 100 g/h | 50 g drink + two 25 g gels | 100 g |
| 120 g/h | 80 g drink + 40 g from gels/food | 120 g |
Do not assume “one bottle per hour” works in every climate. If a bottle contains the full hourly carbohydrate dose, drinking more because it is hot also increases carbohydrate intake; drinking less because it is cold reduces both fuel and fluid. Separating concentrated fuel from plain water can make adjustments easier.
Train the Gut without a Rigid Seven-Week Promise
Practise the same products, dose and timing you intend to use in an event. Begin from an amount already tolerated—not from an arbitrary internet baseline. Increase only one variable at a time so you can identify what caused a problem.
A sensible progression might be:
- Record your present intake during a representative long ride.
- Repeat that dose with consistent timing, such as small portions every 15–20 minutes.
- Add 10–15 g/h on a later long session if symptoms remain mild.
- Hold each new level across several relevant rides before increasing again.
- Test race intensity, heat and climbing separately; tolerance on easy indoor endurance does not guarantee tolerance outdoors at threshold.
- Stop escalating when the plan supports performance and remains practical.
Gut training may improve comfort and carbohydrate handling, but adaptation is individual. There is no evidence-based promise that everyone reaches 120 g/h after seven weeks. A rider who performs well at 75–90 g/h has not failed the process.
Reduce GI Problems by Managing the Whole System
Gastrointestinal symptoms rarely come from one transporter in isolation. Large boluses, highly concentrated bottles, dehydration, excessive fluid, heat stress, very hard intensity, unfamiliar sweeteners, fibre, fat, caffeine and pre-race nerves can all contribute.
Useful troubleshooting steps include:
- Spread intake across the hour instead of consuming the whole dose at once.
- Check whether a gel is intended to be taken with water.
- Avoid testing several new products in the same session.
- Keep pre-event meals familiar and allow enough digestion time.
- Reduce intensity briefly if severe fullness develops; adding water is not automatically the answer if you have already overdrunk.
- Track nausea, bloating, reflux, cramping and stool urgency separately.
Hydrogel, cluster dextrin and “isotonic” are product technologies, not guarantees. Maurten describes its carbohydrate as encapsulated in hydrogel; Skratch uses highly branched cyclic dextrin. Some riders prefer those textures, while others tolerate ordinary drink mix, table sugar, rice cakes or bananas. The best format is the one you can repeatedly consume at the required intensity.
Hydration and Sodium Are Separate Decisions
Carbohydrate, fluid and sodium interact, but they should not be collapsed into one universal hourly formula. Sweat rate varies with body size, power, temperature, humidity, clothing and acclimation. Sweat sodium concentration also varies substantially.
The old draft's blanket 500–800 mg sodium per hour target was too prescriptive. Some riders may need amounts in that range or higher in hot conditions; others need less. Sodium can help replace sweat losses and support fluid retention, but it does not guarantee carbohydrate absorption or prevent all cramps.
Use thirst, known sweat losses, conditions and professional advice where appropriate. Avoid forcing fluid beyond need: overdrinking can cause dangerous exercise-associated hyponatremia. Weighing before and after representative rides can help estimate net fluid loss, but day-to-day conditions still change the answer.
Solids, Gels or Drinks?
Low-intensity early hours often suit solid food because chewing is manageable and savoury options reduce flavour fatigue. As intensity rises, drinks, gels and chews become easier to consume. A mixed plan can preserve appetite while making carbohydrate totals predictable.
Drinks combine fuel and hydration, which is convenient but harder to adjust in changing weather. Gels give precise doses but require opening packets and may become cloying. Solids provide variety but usually include more fat, protein or fibre and can digest slowly at high intensity.
Practise packet handling, bottle concentration and storage. Mark bottles by carbohydrate content rather than assuming all bottles are identical. For a four-hour event, pre-count the total grams and build a contingency for a dropped bottle or missed feed.
Race-Day Example and Decision Rules
For a trained rider targeting 90 g/h over four hard hours, a plan could use 50 g/h from drink plus one 25 g gel and 15 g from chews or food. That equals 360 g across the ride. It should be tested at similar intensity and temperature before race day.
Move toward 100–120 g/h only when the event demands it, 90 g/h is consistently tolerated, carrying the fuel is realistic, and training suggests a benefit. Drop back when symptoms increase, the event is shorter, intensity is low, or the extra intake displaces needed fluid.
High carbohydrate is a tool, not an identity. Consistency at 75–90 g/h usually beats an ambitious 120 g/h plan that becomes impossible after two hours.
Frequently Asked Questions
Will 100 g/h automatically cause weight gain?
No single ride determines body-fat change, but 100 g carbohydrate supplies about 400 kcal. Whether that creates a surplus depends on total daily intake and expenditure. Avoid the inaccurate claim that every hard rider burns 600–1,000 kcal/h or is automatically in deficit.
Can table sugar work?
Sucrose supplies glucose and fructose after digestion and can be a low-cost option. Taste, concentration and tolerance matter. Measure grams carefully and test the mixture in training.
Is 120 g/h only for professionals?
Not exclusively, but evidence is concentrated in trained populations. Most riders should establish a reliable 60–90 g/h plan before considering it.
Should every gel be taken with water?
Follow the product directions. Some are designed for use without immediate water; others are concentrated. Hydration still matters across the ride.
Does sodium prevent cramps?
Not reliably. Exercise-associated cramps are multifactorial. Replace fluid and sodium according to individual losses rather than treating salt as a guaranteed cure.
What should I do if symptoms keep recurring?
Reduce the dose, simplify ingredients, review meal timing and consult a sports dietitian or clinician—particularly if pain, vomiting, diarrhoea, bleeding or symptoms outside exercise occur.
How do I count carbohydrate per hour?
Add up the grams of carbohydrate on the label of everything you eat and drink in an hour. A 50 g drink serving plus two 25 g gels, for example, gives 100 g per hour, the same arithmetic used in the table above. Check each label, because serving sizes and carbohydrate content differ between products and flavours.
Products and Sources
- Maurten Gel 100 — 25 g carbohydrate per sachet.
- Science in Sport Beta Fuel 80 — 80 g dual-source carbohydrate per serving.
- Skratch Labs Super High-Carb Drink Mix — approximately 50 g carbohydrate per current serving.
Affiliate disclosure: RydeCruz may earn a commission from qualifying purchases made through affiliate links, at no extra cost to you. Product availability and prices can change.
Research references: multiple transportable carbohydrate guidance, 90 versus 120 g/h oxidation study, graded carbohydrate and critical power, and contemporary carbohydrate-guideline review.
