Hikers, how can you stay properly hydrated?


Hiking is both a leisure and discovery activity and a form of physical exercise. The length of your walk and the cold or intense heat will require a great deal of energy. Dry mountain air may accelerate dehydration. Keeping hydrated when hiking is essential to derive the maximum benefit from your efforts and to enjoy the landscapes and get away from it all.

1 - Drink a minimum of 1.5 litres of water per day

An adult loses an average of 2.5 litres of water per day. Our body is constantly eliminating water or water vapour from the kidneys, intestine, lungs and skin.

This water loss must be offset by consuming food and drinks. Since food provides approximately 1 litre of water, drinks must provide the other 1.5 litres. Hence this specific quantity. And when I am talking about drinks, I mean water.

Why a minimum of 1.5 litres? Your needs increase depending on the climate or when in a dry atmosphere (as is the case in the mountains), but above all during physical activity.

2 - Don't wait until you're thirsty before drinking

Your body cannot store up water. This is why I recommend that you drink regularly. However, do not wait until you feel thirsty before drinking; this is not a good indicator. This sensation occurs when your body is already dehydrated by at least 1% of your body weight.

Did you know? Thirst perception decreases with age.

3 - Drink regularly while hiking!

Physical effort raises your body temperature. In order to evacuate this heat, your body uses a cooling system: perspiration. 80% of excess heat is evacuated through this highly effective system.

Water loss linked to perspiration is between 0.5 and 1 litre per hour. This may rise to 3 litres, or even more, depending on the climate and the intensity of your walk. You will thus see how important it is to offset these losses during physical effort when you know that dehydration is one of the main causes of fatigue and a drop in performance.

Conclusion: Drink a minimum of 0.5 litres of water or drinks per hour of physical effort.

4 - Keep hydrated before, during and after your hike!

  • Before: Hydration starts before your exertion in order to prevent the water loss which will occur during the hike.
  • During: You must make up for the water loss caused by perspiration, thus limiting dehydration.
  • After: Hydration is also necessary after physical effort to ensure proper recovery. A hike lasting several hours will result in slight dehydration, which may cause muscle pain.

5 - Take the right drinks on your hike!

  • For walks of less than an hour, you won't need anything other than water.
  • After this, you may also need carbohydrates to avoid hypoglycaemia and a drop in energy. An isotonic drink is perfect to meet your energy needs. You should avoid fizzy or energy drinks, which are often too sugary and actually speed up dehydration.

Ensure that your drink is not too cold; this could cause gastric problems. The perfect temperature for your drink is around 15°C.

6 - Stay on the alert for the first signs of dehydration:

The main symptoms of dehydration are:

  • Feeling thirsty,

  • An increased heart rate,

  • A drop in blood pressure,

  • A drop in performance.  

The first signs of dehydration will be fatigue and weariness while walking. More intense dehydration results in great thirst, heavy legs, breathlessness, muscle and tendon pain; this could lead to injury. Don't hesitate to consult a doctor if necessary.

Marie Fauchille
Dietician | Nutritionist
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      Water accounts for 60% of the weight of a human being. It is the main component of our body. Therefore, dehydration can have a serious effect on the body, because water intervenes in a many of the chemical reactions that make our body function properly. All forms of physical activity produce heat that must be eliminated. This is the reason why we perspire, a phenomenon that incurs the risk of dehydration.


      Your body needs water. For happy and healthy body, you need to compensate for water loss. Before, after and especially during physical exertion, dehydration is any athlete's worst enemy, affecting both the body and sporting performance. That's why staying properly hydrated is essential for all of us. This is why the Aptonia blog is going to publish its first report on the benefits and signs of good hydration for athletes. Firstly, here are 6 tips for staying efficiently hydrated before, during and after exercise.