Written by: Martijn Redegeld
In the previous blog you could read how many carbohydrates you need during different types of exercise. And while all carbohydrates provide energy to the body, not all carbohydrates are exactly the same. For example, differences between carbohydrates cause differences in the speed and ease with which they are digested or absorbed into the body. You can read in this blog which type of carbohydrates are best for your training or competition.
In summary:
- While all carbohydrates provide energy, they are not all created equal. For example, the speed at which different products are digested and with which the carbohydrates are ultimately absorbed differs.
- During a quiet endurance exercise, it can be pleasant to choose solid food products that are digested more slowly and provide energy for a longer period of time. During intensive exercise, it is advisable to choose products that are quickly digested and provide energy in a short time.
- For intakes above 60 grams of carbohydrates per hour (recommended from 2 hours of exercise), the glucose-fructose ratio of products should be taken into account. A 2:1 ratio is ideal to achieve maximum carbohydrate intake.
- With intakes above 90 grams of carbohydrates per hour (recommended during very extreme efforts), the 1:0.8 ratio is ideal to achieve these extremely high intakes.
- To prevent stomach or intestinal complaints, it is important to train regularly with these types of high intakes, and to gradually increase the intake.
The role of the glycemic index in energy intake for maximal performance
Shortly before or during exercise, it is desirable that the energy from an energy drink, energy bar or energy gel is absorbed into the body as quickly as possible. For this it is important that the products are digested and absorbed as quickly as possible. The glycemic index is a score for the speed at which all this happens: when a product has a high glycemic index, it means that the carbohydrates are absorbed quickly, a low score means that this process takes a lot more time.
The glycemic index of a product is ultimately determined by the combination of ingredients in a product, method of preparation and the possible presence of nutrients other than carbohydrates. For example, the Amacx Energy Oat Bar will have a lower index than the Amacx Fruit Chew, because the Energy Oat Bar is an oatmeal bar and therefore contains more fibres, proteins and fats that are digested more slowly. Energy drinks and energy gels, which consist of the fastest absorbable sugars at Amacx, have an even higher glycemic index and are absorbed even faster than energy bars.
The effect of different ingredients on digestion and absorption
In addition to the difference between solid and liquid form of a product, and the fiber content of a product, other ingredients also contribute to the speed of digestion and absorption. As a rule of thumb, it can be assumed that nutrients other than carbohydrates (eg proteins or fats) slow down this process considerably. All this also ensures that the risk of stomach or intestinal complaints increases substantially during exercise, especially when the stomach and intestines are shaken up and down as a result of the effort (such as during running). If you are sensitive to these types of complaints, it is therefore recommended to choose products that are digested as quickly and easily as possible.
Product |
Average food absorption |
Energy Oat Bars |
Relatively slow and gradual |
Fast Bars & Energy Fruit Chew |
Mediocre |
Energiegel of isotone drank |
Relatively fast |
Glucose or fructose?
In addition to the above factors, the type of sugar in an energy drink, energy bar, or energy gel also plays a role in the extent to which the body can absorb the carbohydrates. After the digestion of carbohydrates, loose sugar molecules remain in the intestines, in particular glucose and fructose from Amacx's sports nutrition products. From the intestines, these two sugars are absorbed into the blood via separate absorption systems, and then transported throughout the body. These intake systems can be compared to a revolving door that only lets glucose or fructose through. Both revolving doors can absorb the sugars at a maximum rate: for the glucose system that is about 60-70 grams per hour, while for the fructose system it is about 30-50 grams per hour.
When the duration of your exercise is longer than 2 to 2.5 hours and it is recommended to take more than 60 grams of carbohydrates per hour, it is important to carefully adjust your intake to these different sugar sources. After all, both recording systems must then be used side by side. Because the glucose system can absorb twice as much per hour as the fructose system, the bars, gels and/or sports drink should have a 2-to-1 ratio between glucose and fructose. Only then will you be able to absorb these relatively large amounts of carbohydrates without any problems, up to about 90 grams per hour. So pay close attention to this when choosing the right products. Examples of these products are the Amacx Isotonic Energy Drink, Amacx Drink Gel and the Amacx Fast Bar.
The role of Amacx Turbo products with a 1-to-0.8 ratio
If your efforts are very extreme in duration and/or intensity, such as riding the Amstel Gold Tour or (multi-day) mountain bike marathon, the carbohydrate consumption will be even higher. In such situations, a carbohydrate intake of 90 to 120 grams per hour could provide additional added value. At these extremely high intakes, the relative share of fructose becomes somewhat larger, and products with a 1-to-0.8 ratio are recommended. This can be found in the Amacx Turbo Drink, Amacx Turbo Gels and Amacx Turbo Chew.
In all cases, keep in mind that it is crucial to structurally train the stomach and intestines to achieve these high carbohydrate intakes. You can read more about this in our blog about training the stomach and intestines.