Carbohydrates are their primary source of fuel. During a stage at the Tour, our riders will often consume 120 grams of carbs per hour in the form of easily digestible Amacx bars, gels, and drink mixes. Research shows that higher in-race carb intake improves endurance performance and recovery, especially in intense stage races like the Tour de France. Absorbing that much energy while racing flat-out through farmers’ fields and villages or climbing Pyrenees or Alps is a huge challenge. Our nutrition team works with our riders in the months leading up to the race to help them train their guts for maximum carbohydrate absorption.

Team nutritionist Amaia Martioda has drawn insights from our squad’s gut training process and adapted those lessons for you so that you can better fuel your own endurance efforts.

First, you want to understand when upping your carb intake will benefit your performance.

The number of grams of carbs that you should consume per hour during your own training and racing depends on the intensity and duration of your efforts. Most amateur riders will do best with 60-90 grams per hour with a 2:1 ratio of glucose to fructose for most of their rides.

Glucose and fructose are different types of sugars, which are absorbed into your bloodstream via different pathways to be used for fuel. Research shows that the human body is able to absorb approximately 60 grams of glucose per hour. To increase the total amount of carbohydrate your body has available to burn beyond that limit, additional carbs should be consumed in the form of fructose, a sugar derived from sources such as fruit and honey that is processed in the liver to produce glucose, glycogen, and lactate.

Amacx Energy gels, bars, chews, and drink mixes contain glucose and fructose in a 2:1 ratio. They are easily digested and a great source of fuel for most training sessions and races.

Say you have a hard three-hour race coming up. You could plan to drink one bidon with Amacx Energy drink every hour and eat an Amacx Energy bar, chew, or gel every 30 minutes. Every product in the Amacx Energy line contains 30 grams of carbs, with 20 grams of glucose and 10 grams of fructose per serving. So, you could plan to take in 90 grams of carbs per hour, hitting your 60 grams of glucose maximum every hour, with 30 additional grams of fructose. Most athletes should be able to stomach this amount of fuel easily, although it is always a good idea to practice using the food and drink that you are going to use in your race during your training sessions, especially in the weeks before your key event.

Amacx’s Turbo line is designed for extreme endurance performance in long, hard events like the Tour de France. Amacx Turbo bars, gels, and drinks up the concentration of fructose relative to the Amacx Energy line. Every Amacx Turbo product contains glucose and fructose in a 1:0.8 ratio. This allows for greater carbohydrate absorption.

Say you have a hard six-hour race coming up. Research shows that you will likely perform better if you are able to up your carbohydrate intake from 90 grams to 120 grams per hour, as our riders do during the hardest stages of the Tour de France.

You could achieve this by drinking one bottle of Amacx Turbo drink containing 40 grams of carbs in a 1:0.8 ratio every hour — that is 22.22 grams of glucose and 17.8 grams of fructose – and then eating one Turbo Gel or pack of Turbo Chews every 30 minutes. Each contains 40 grams of carbs with the same ratio of glucose to fructose, so you would be taking in 66.6 grams of glucose per hour — about the upper limit – plus 53.34 grams of fructose. Most racers should be able to stomach that amount easily after some gut training practice.

The human gut is very adaptable. Research shows that consuming carbohydrate-rich foods can improve athletes’ ability to absorb carbs and turn them into fuel, especially during intense exercise.

Our team uses a three-step gut-training process to get ready for events like the Tour de France and make sure that they don’t suffer from gastrointestinal distress.

First, we make sure that our riders' stomachs can handle the volume of food and drink that they will need to consume hour after hour during the race using Amacx’s Energy line. Then, we add extra fructose via Amacx Turbo products to help them train their digestive pathways to turn fructose into glucose for fuel quickly. Once they can tolerate the additional fructose well, they practice upping the intensity of their training to simulate race efforts, while consuming 120 grams of carbs per hour.

Amaia goes into further detail about each step below.

It is important to understand that if you can't eat and drink every 15 minutes, or eat an energy bar every 30 minutes in training, you are not going to be able to do it in racing.

The first step for an athlete is to be able to eat around 60 grams of carbohydrate worth of solid food and to drink an isotonic drink, like Amacx Energy, with about 30 grams of carbs every hour. For a three-hour ride, you want to be able to do 90 grams per hour.

You can train this timing and adapt the stomach to be able to process this food and fluid and move it to the intestine. It’s in the intestine where the molecules will be absorbed. Getting to 90 grams per hour is a good first step.

You basically want to get in the habit of always eating or drinking something every 15 minutes. Amacx Energy bars are 30 grams per unit. So, if you want to maintain 90 grams per hour, you can take two energy bars and a full bidon of Amacx Energy drink per hour.

Once you can eat 90 grams per hour, you can start training your dose of fructose. We increase the amount of fructose our riders are having by using Amacx Turbo products.

If you are going to do more than three hours with intensity, you run into a barrier for absorption of enough of the different types of sugar molecules. At a very basic level, it is like there is a wall in our intestines and we have specific doors to absorb carbs. Glucose goes through a different door than fructose, and there are more doors for glucose than fructose. If you want to improve how many carbs you can absorb during an hour, you need to improve how many carbs can go through those doors. The greatest improvement can come from letting through more fructose.

Sometimes, some riders can have issues, such as nausea or bloating, because their transport systems haven’t adapted – their doors for glucose and fructose don’t open wide enough – and they need time. You might need a month or two months to feel better. Our advice is not to overstress the system. If you are not feeling so good with the extra fructose, add it little by little and take more time. The benefits will develop in the long term.

The most common mistake that riders make is thinking that they can hydrate with Turbo and then getting cramping during their race or training session. They might think they need more sodium then, but the problem is that they are not hydrating. Concentrated energy drinks like Amacx Turbo are for fuelling, not hydration. To hydrate, you need to drink water or isotonic drinks like Amacx Energy Drink. They are for two different things.

Over time, you will get better at digesting fructose, but it is something you need to practice during your training sessions, because we each have an individual response to this stimulus.

The third step is to try to consume this quantity of energy when you are riding hard. Consuming 120 grams of carbohydrate at an easy pace is not the same as doing it when you are breathing hard and your whole body is in race mode. Once you can get up to 120 grams at the 1:08 ratio of glucose to fructose from Amacx Turbo, try to maintain this ratio by pushing more intensity.

Sometimes, we do this in racing, and sometimes in training, because it can be difficult to simulate race efforts.

Racing with Amacx Turbo takes practice at first, because you are consuming more on the bike than you are used to. It’s not as if you are consuming more than you are burning when you use Turbo, but you might not be hungry right when you get home. And if you drink your recovery drink right after your session, you might not need so much carbohydrate to recover.

But, for recovery from a race or high-intensity training session, replacing the amount of carbohydrate that you used is really important. That is one great benefit of training your gut to consume more carbs on the bike, especially at a stage race like the Tour de France. If you can consume 120 grams of carbs per hour in the race, you won’t only perform better on the day, you will not have to eat such an extreme amount of food afterwards to recover, which will put less stress on your digestive system, and help you perform better the next day as well.

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