Der WUT-Index: Bist du gut hydriert für den Tag

The WUT Index: Are you hydrated for the day?

Dehydration is a problem, not only in everyday life but especially for endurance athletes. It can lead to various health problems. The good news is that it is easy to prevent dehydration by paying attention to your fluid intake.

One way to do this is with the WUT Index (Weight, Urine, Thirst). It is a simple tool that can help you assess your hydration status. Urine colour alone is not always sufficient. It is most reliable when you observe it in the morning after waking up. If you have persistent problems, we strongly advise you to discuss this with a doctor.

The index is based on three factors:


  • Weigh yourself directly after waking up and before going to the toilet to measure your fluid loss.
  • A fluid loss of more than 1-2% of your body weight can already cause performance losses.
  • Give yourself one point if you have lost more than 1-2% of your body weight compared to the previous day.

Urine Colour:

  • Next, pay attention to the colour of your urine. Here too, you get one point if it is very dark.
  • Dark urine (dark yellow or orange) can be a sign of dehydration.
  • Light urine (light yellow or almost clear) is a sign of good hydration.
  • The colour of your urine is a good indicator of your hydration status, but it is important to note that some medications can affect the colour of your urine.


  • Thirst is a sign of dehydration, but it is not a reliable indicator. Waiting until you are thirsty to drink is already a sign of mild fluid deficiency. Drink regularly, even if you are not thirsty, to avoid dehydration.
  • You get another point if you wake up feeling thirsty. This means that you can get a maximum of 3 points, which is not a good thing in this case. This is a very simplified approach, but it gives you an orientation.


  • 0-1 points: You are well hydrated.
  • 2 points: You are slightly dehydrated. Try to drink more fluids throughout the day and, as an active person, you should also make sure to replenish some of them with electrolytes.
  • 3 points: You are probably dehydrated. Make sure to drink more and also with electrolytes, as this will help you get back into balance faster than if you only drank water.


This tool can help you, if you are healthy, to pay a little more attention to drinking enough, and this is especially important in endurance sports. It is particularly useful when you are in training phases with a high workload or to make sure that you are well hydrated before the next session. You can see it as a small monitoring tool for your fluid balance.

However, every rule of thumb has its weakness, as it cannot be the explanation for everything. The one-point scale is very simplified and could be further divided into nuances. Therefore, we would like to point out again that you should please consult a doctor if the condition persists.


Back to blog

Leave a comment

Please note, comments need to be approved before they are published.