We regularly receive questions about nutrition and sports nutrition.
Questions such as: which sports nutrition should I now take when? How do I deal with sports nutrition? What should I drink?

Our vision is that to understand well when you take what you need to have information about which energy sources your body works on. When do you use which energy source and how long can you maintain this.

Energy systems
Our body gets its energy mainly from four components: phosphate (fuel) carbohydrate (fuel) fed (Fuel and building material) and proteins (mainly a building material, but if the carbohydrates are used, as well as fuel).

Depending on the demand for energy and availability, the body chooses the correct component to "burn". In endurance sports, use is made of the oxygen energy system (aerobic energy system) and therefore the combustion of carbohydrates and fats† In competition sports there must often be accelerated or sprints. In this case, very briefly addresses the phosphate system and then the combustion of only carbohydrates in the oxygen-energy system (Anaerobic energy system). The disadvantage of this is that in this system, among others, H+ ions are released that cause the acidification in the muscles.

In addition to the aforementioned energy components, our body also needs vitamins, minerals and sufficient water to properly process the nutrients in food into energy. The amount of energy that a basic component provides to our body is different.

For example, 1 gram yields:

  • 1 gr carbohydrates 4.1 kcal energy
  • 1 gr fat 9.3 kcal energy
  • 1 gram protein 4.0 kcal energy

To burn this energy there is oxygen Needed with carbohydrates per liter of oxygen yields the most energy (5 kcal. For comparison: fats: 4.7 kcal and proteins 4.5 kcal).

The disadvantage of carbohydrates is that these are only limited in our body. In our body we only have carbohydrates for a maximum of 1.5 hours on. Depending on the demand for energy and availability, the body chooses to "burn" fats and/or carbohydrates. Carbohydrates are stored in the form of glycogen and blood glucose Easily available and provide a lot of energy. Fats provide significantly less energy and it takes the body more effort to burn it. The stock of subcutaneous fatty tissue is countless larger than the stock of carbohydrates in the most trained cyclists.

Example: It is calculated that with an average efficiency and aerodynamics it costs around 21 kcal per minute to cycle at 40 km/h. The body can store around 2000 to 3000 kcal in carbohydrates, so that means that there is approximately fuel for just 90 minutes. A cyclist of 70 kg with an average build has stored around 125,000 kcal as fat. That means that the body can theoretically bicycle for 110 hours or 4.5 days on this intensity on this intensity.

In the formula below you can see that more than 4x as much oxygen (O2) is required for fat burning (23 O2) than with the combustion of carbohydrates (6 O2)

Carbohydrate combustion: Glucose + 6 O2 + 36 PI + 36 ADP -> 6 CO2 + 42 H2O + 36 ATP

Fat Burning: C16H32O2 (= fatty acid; palmitate) +23 O2 + 129 (ADP + PI) -> 129 ADP + 16 CO2 + 145 H2O

Do you know: In the fat burning process, much more water (H2O) is also released than when burning of carbohydrates (145h2o compared to 42h2o), this also explains why you lose much more moisture at low intensity.

Because endurance athletes use a lot of carbohydrates, they have to eat carbohydrate -rich. The advised food percentages for endurance athletes is: 60 % carbohydrates, 15 % proteins and 25 % fats† Often athletes eat too much fat and too little carbohydrates. A vitamin B, iron and magnesium deficiency can also easily arise because they are involved in the energy supply.

Be careful for a protein deficiency, because it is at the expense of muscle mass. Proteins are the building blocks of the muscles. However, the protein share in the total energy value of the meal should not be too large. The number of calories that you burn per day depends on your activities, weight, age and gender.

Tip: Do you want sound advice about the composition of your meals? Then contact a specialty sports nutrition diet (e).

The total calorie burning per day consists of the resting metabolism (or Basal Metabolic Rate) plus the energy needed for all your activities. With an average man/woman this is 2500/2000 kcal per day. Cycling is a typical endurance sport, because energy has to be supplied at a relatively constant level in a longer period of time. You in particular tax the aerobic energy system (the combustion where oxygen is needed)

With a low heart rate, the basis for energy supply is the combustion of fats. This combustion takes "more" time and is difficult to start, but ultimately provides more energy. However, if the sport lasts a little longer or becomes more intensive (sprinting, cycling harder), the body will mainly use carbohydrates. So if you mainly want to train your fat burning, you will have to cycle long pieces on low intensity.