Fuelling Recommendations in Triathlon: Why the 60g Per Hour Ceiling Has Changed

By: Coach Jenna-Caer Seefried

For a long time, endurance athletes were told there was a ceiling.

Sixty grams of carbohydrate per hour.

That number became one of those rules athletes repeated without always understanding where it came from. If you were racing long course triathlon, you aimed for 60g per hour, maybe a little more if you were brave, but anything beyond that was often treated like a fast track to gut disaster.

Then endurance sport moved forward.

Now we are seeing elite long course triathletes regularly target 90-120g of carbohydrate per hour, and in some cases even higher. This is not because athletes suddenly developed stronger stomachs overnight. It is because our understanding of carbohydrate absorption, gut training, fuelling products, and race execution has evolved.

The old ceiling was not completely wrong. It was just incomplete.

Why 60g Per Hour Was Once Considered the Limit

The 60g per hour recommendation was largely based on how much glucose the body could absorb and use during exercise.

Glucose uses a transporter in the small intestine called SGLT1. That pathway can only move so much carbohydrate across the gut wall at one time. Once that pathway is saturated, adding more glucose does not necessarily mean more usable energy. It can just mean more carbohydrate sitting in the gut, which often leads to bloating, cramping, nausea, or the urgent need to find a porta potty. Not ideal when you are trying to race. Research reviews explain that glucose oxidation from a single carbohydrate source tends to be limited, which is why older guidelines often recommended around 30 to 60g of carbohydrate per hour for endurance exercise.

This is where a lot of athletes got stuck.

They assumed that if 60g was the limit, there was no point trying to take in more. But the real issue was not that the body could not use more carbohydrate. The issue was that athletes were mainly relying on one absorption pathway.

The Shift: Multiple Transportable Carbohydrates

The breakthrough came from understanding that different types of carbohydrate use different transporters in the gut.

Glucose uses SGLT1.

Fructose uses GLUT5.

When you combine glucose and fructose, you are no longer trying to force everything through one overloaded pathway. You are using two separate routes to absorb carbohydrate, which allows the body to take in and oxidize more fuel during prolonged exercise. This is why glucose plus fructose combinations have become standard in higher carbohydrate race fuelling. Multiple transportable carbohydrate research supports that glucose and fructose blends can increase carbohydrate oxidation and improve endurance performance compared with glucose alone, especially during longer events.

In practical terms, this is what made 90g per hour possible.

For events lasting longer than about two and a half to three hours, sports nutrition guidance has commonly supported carbohydrate intakes up to around 90g per hour when using multiple transportable carbohydrates.

That matters in triathlon because long course racing is not just about fitness. It is about preserving your ability to produce energy for hours.

You are not fuelling the bike alone. You are fuelling the run that comes after it.

Why This Matters So Much in Triathlon

Triathlon is brutally honest.

You can be fit. You can have done the work. You can have nailed the long rides, hit the intervals, and built a strong engine.

But if you underfuel, the race will eventually collect.

In a 70.3 or Ironman, underfuelling does not always feel dramatic at first. It can start quietly. Power drops a little. Focus slips. Your ability to hold position starts to fade. You stop making smart decisions. Then you hit the run and wonder why your legs have completely abandoned you.

A lot of athletes call this a fitness problem.

Sometimes it is not.

Sometimes it is a fuelling problem.

When glycogen availability drops and carbohydrate intake is too low, athletes struggle to maintain intensity late in prolonged endurance exercise. Carbohydrate intake during exercise helps preserve performance by providing an external fuel source when internal stores are being depleted.

That is why modern triathlon fuelling has become much more intentional.

It is not just “take a gel when you remember.”

It is grams per hour.
Fluid per hour.
Sodium strategy.
Gut tolerance.
Timing.
Practice.
Execution.

The athletes racing well today are not just training harder. They are fuelling better.

Why More Carbs Is Not Automatically Better

This is the part athletes need to respect.

Just because some athletes can take in 90g, 100g, or more per hour does not mean you should suddenly try that on race day.

That is not bravery. That is sabotage.

Your gut needs to be trained.

The gastrointestinal system can adapt when carbohydrate intake is practised during training. Athletes who want to tolerate higher intakes need to expose the gut to those intakes gradually, especially during race specific sessions where intensity, heat, hydration, and duration create real demands. Research and current practice both emphasize that high carbohydrate intake should be trained, not improvised.

Start by knowing where you are.

If you currently take in 40g per hour, jumping to 90g overnight is a bad idea. A better approach is to increase gradually during key long rides and brick sessions. Test products. Test timing. Test concentration. Test how it feels when you are riding at race intensity, not just cruising around feeling fresh.

Your stomach is part of your race system.

Train it.

Practical Fuelling Targets for Triathletes

There is no single number that works for everyone, but here is a useful starting framework.

For shorter sessions under 60 to 75 minutes, you may not need much carbohydrate during the session, depending on the intensity and what you ate beforehand.

For sessions around 90 minutes to two and a half hours, many athletes do well with roughly 30 to 60g per hour.

For long course specific sessions over two and a half hours, especially rides and bricks, working toward 60 to 90g per hour can be useful.

For Ironman and 70.3 racing, many competitive athletes now practise higher intakes, often around 90g per hour, using glucose and fructose blends. Some highly trained athletes may tolerate more, but this needs to be built carefully and individually. Current endurance nutrition guidance commonly supports intakes up to 90g per hour for longer endurance events, particularly when using multiple transportable carbohydrates.

The key is not chasing the biggest number.

The key is finding the highest amount you can tolerate and use effectively while still racing well.

What to Look for in Your Fuelling Products

If you are aiming above 60g per hour, you need to pay attention to the type of carbohydrate.

Look for products that use multiple transportable carbohydrates, commonly glucose, maltodextrin, and fructose. Maltodextrin behaves similarly to glucose in this context, while fructose uses a different transporter. This combination helps increase total carbohydrate absorption compared with relying on glucose alone.

You also need to think about delivery.

Some athletes prefer drink mix.
Some prefer gels.
Some use chews.
Most long course athletes use a combination.

The practical question is not just “how many carbs are in this?”

It is:

Can I access it while riding?
Can I tolerate it at race intensity?
Does it work in heat?
Can I repeat this for several hours?
Does it still appeal to me late in the race?

Fuelling is not theoretical. It has to work when your heart rate is up, your hands are sweaty, the road is rough, and your brain is getting loud. I love to use Maurten to make sure I can get in as much carbohydrate as possible.

The Bike Is Where Most Triathletes Win or Lose Their Run Fuelling

The bike is the best opportunity to fuel.

You are more stable than on the run. You can carry more. You can take in fluids and carbohydrates more consistently. If you underfuel here, you put yourself in a hole that is very hard to climb out of later.

The mistake is waiting until you feel low.

By the time you feel underfuelled, you are already behind.

A strong bike fuelling plan starts early and stays consistent. That might mean taking in carbohydrate every 10 to 15 minutes, or using a bottle based strategy where you know exactly how many grams you need to drink per hour.

Do not leave it to vibes.

Vibes do not get you through the last 10km of a 70.3 run.

Fuelling Is Also a Recovery Tool

Fuelling during training does not just help you complete the session. It helps you absorb the work.

Athletes who chronically underfuel key sessions often struggle with poor recovery, low energy, inconsistent performance, and excessive fatigue. Carbohydrate availability plays an important role in supporting training quality and recovery, especially during repeated endurance sessions.

This matters for age group athletes because most are not just training.

They are working. Parenting. Travelling. Managing stress. Trying to squeeze training into real life.

If you underfuel a key session, then rush into a full workday, sleep poorly, and try to train again the next morning, you are not being tough. You are digging a hole.

Better fuelling allows better training.

Better training creates better adaptation.

Better adaptation creates better racing.

The Bottom Line

The 60g per hour ceiling changed because the strategy changed.

Once athletes moved beyond relying on one carbohydrate pathway and started using glucose and fructose together, higher carbohydrate intake became possible. Not for everyone immediately. Not without practice. But possible.

That shift has changed endurance sport.

Triathletes are now racing faster, recovering smarter, and executing with more precision because fuelling is finally being treated like a performance system, not an afterthought.

But the principle is still simple.

You cannot access fitness you have not fuelled.

At MNA, fuelling is part of the plan. We help athletes practise race day nutrition in training, build gut tolerance, and develop strategies that fit the athlete, the distance, the conditions, and the goal.

Because race day execution is not just about how fit you are.

It is about how well you can use that fitness when it matters.

-Coach Jenna-Caer