From February 25 to March 4, Hydratis sets up at the foot of the slopes of La Plagne with a unique setup: the Winter Lab, a space entirely dedicated to the prevention and optimization of hydration at altitude.
While the mountains spontaneously evoke images of fresh air, performance, and exertion, they are also a physiologically demanding environment. Cold, altitude, dry air, and physical activity combine to increase fluid loss, often without you being fully aware of it.
Through this field activation, Hydratis wants to put hydration back at the center of your resort experience.
The Hydratis Winter Lab: a scientific approach at the foot of the slopes
To raise awareness among holidaymakers in a concrete way, Hydratis is setting up an experiential space in La Plagne entirely dedicated to hydration.
The Winter Lab offers a tasting area where visitors can discover the different flavors in the range. The goal is to encourage regular, convenient hydration adapted to winter conditions.
A personalized hydration testing area is also available by appointment. Guided by the Hydratis scientific team, participants can measure their body hydration levels and gain a better understanding of their individual needs. This educational approach transforms theoretical data into concrete, personalized information.
Conferences and sporting activities complement the program, including a presentation on the importance of hydration at altitude led by Jonathan Lamy (ESF instructor, firefighter and mountaineer), as well as a guided snowshoeing trip to experience the effort in real conditions.
A social space finally allows these experiences to be shared and awareness to be amplified around the challenges of hydration in winter.
Why do we become dehydrated more quickly at altitude?
From an altitude of 1500 meters, your body must adapt to several physiological constraints.
Oxygen depletion leads to an increase in respiratory rate. Each additional respiratory cycle increases fluid loss through respiration. The cold, dry air of ski resorts further accentuates this phenomenon (Sawka MN et al., 2000).
Altitude also stimulates what is known as "altitude diuresis," an adaptive mechanism that increases the elimination of water and electrolytes. Therefore, you lose more fluids, even if you don't feel like you're sweating (Schmidt et al., 1997).
In winter, an additional factor comes into play: the sensation of thirst can decrease by up to 40%. In other words, the physiological signal that is supposed to prompt you to drink becomes less reliable, while your needs increase (Kenefick RW et al., 2004).
As a result, dehydration is likely to set in gradually and often silently.
However, a water loss corresponding to only 2% of body weight can already lead to a significant decrease in physical performance, up to 20%, as well as an increase in fatigue, headaches and general discomfort (Cheuvront SN & Kenefick RW, 2014).
How much water should you drink in the mountains?
Water requirements vary according to altitude and activity level (Butterfield GE et al., 1992).
At altitudes between 1500 and 2500 meters, a daily intake of approximately 2.5 to 3 liters of water is recommended for a relatively inactive person. These needs increase with regular physical activity such as skiing, hiking, or snowboarding.
Above 2500 meters, it is advisable to aim for 3 to 4 liters per day, or even more if the effort is intense or prolonged (Hannon JP & Sudman DM, 1973; Wagner PD et al., 1986).
Above 4000 meters, particularly in mountaineering, the needs can reach 4 to 5 liters per day (Pugh LGCE, 1964)
These intakes must be spread throughout the day in order to maintain a stable fluid balance and limit significant fluctuations in plasma volume.
Why electrolytes play a key role at altitude
Hydration is not just about the volume of water consumed. Losses due to altitude and exertion also affect electrolytes, particularly sodium, potassium, and magnesium.
These minerals contribute to fluid balance, nerve transmission, and muscle function. Their presence promotes efficient intestinal water absorption via sodium-glucose co-transport mechanisms and contributes to better fluid distribution in the body (Jeukendrup AE & Moseley L, 2010).
In the mountains, where losses are increased and sensations can sometimes be misleading, electrolyte intake becomes a strategic lever to support truly functional hydration.
Hydratis: a brand committed to better understanding hydration
Founded in 2019, Hydratis has set itself the mission of democratizing more effective and conscious hydration.
Faced with the fact that nearly 4 out of 5 French people do not drink enough water (IFOP study for Hydratis, April 2025), the brand is developing solutions adapted to everyday life but also to specific situations such as exertion, heat, travel or altitude.
Hydratis lozenges combine electrolytes and trace elements, including magnesium, potassium, zinc and manganese, to support hydro-electrolytic balance and optimize water absorption.
Present in more than 11,800 pharmacies and used by several million people in France, Hydratis continues its commitment on the ground by meeting practitioners in demanding environments such as the mountains.
In winter, hydration remains a priority
Contrary to popular belief, the risk of dehydration does not disappear with cold weather. It simply becomes less noticeable.
Between the altitude, the dry air, the increased ventilation and the decreased sensation of thirst, the mountains constitute an environment where the water balance is put to the test.
Incorporating a regular hydration routine, adapted to your activity level and altitude, is a key factor in preserving your energy, comfort and recovery.
With the Winter Lab in La Plagne, Hydratis reminds us that hydration is a pillar of performance and well-being, summer as well as winter.
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