From February 25 to March 4, Hydratis is setting up at the foot of the La Plagne slopes with a unique initiative: the Winter Lab, a space entirely dedicated to the prevention and optimization of hydration at high altitudes.
While mountains naturally evoke clean air, performance, and effort, they are also a physiologically demanding environment. Cold, altitude, dry air, and physical activity combine their effects and increase fluid loss, often without you being fully aware of it.
Through this on-site activation, Hydratis aims 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 practical way, Hydratis is setting up an experiential space entirely dedicated to hydration in La Plagne.
The Winter Lab offers a tasting area to discover the different flavors of the range. The objective is to encourage regular, practical, and winter-condition-adapted hydration.
A personalized hydration testing area is also available by appointment. Accompanied by the Hydratis scientific team, participants can measure their body hydration level and better understand their individual needs. This educational approach transforms theoretical data into concrete and personalized information.
Conferences and sports activities complement the initiative, including a talk on the importance of hydration at altitude led by Jonathan Lamy (ESF instructor, firefighter, and mountaineer), as well as a guided snowshoe outing to experience effort in real conditions.
Finally, a social space allows for sharing these experiences and amplifying awareness about the challenges of hydration in winter.
Why do we dehydrate faster at altitude?
From 1500 meters altitude, your body must adapt to several physiological constraints.
Oxygen rarefaction leads to an increase in respiratory rate. Each additional respiratory cycle increases fluid loss through the respiratory tract. The cold, dry air of ski resorts further accentuates this phenomenon (Sawka MN et al., 2000).
Altitude also stimulates diuresis, known as "altitude diuresis," an adaptive mechanism that increases the elimination of water and electrolytes. You therefore 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 encourage you to drink becomes less reliable, while your needs increase (Kenefick RW et al., 2004).
Result: dehydration is likely to set in gradually and often silently.
However, a fluid 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?
Fluid needs vary depending on altitude and activity level (Butterfield GE et al., 1992).
Between 1500 and 2500 meters, a daily intake of approximately 2.5 to 3 liters of water is recommended for a less active person. In case of regular physical activity such as skiing, hiking, or snowboarding, these needs increase.
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, especially in mountaineering, needs can reach 4 to 5 liters daily (Pugh LGCE, 1964).
These intakes should be spread throughout the day 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 related to altitude and effort also concern electrolytes, especially sodium, potassium, and magnesium.
These minerals contribute to fluid balance, nerve transmission, and muscle function. Their presence promotes efficient water absorption in the intestine, 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 are sometimes misleading, electrolyte intake becomes a strategic lever to support truly functional hydration.
Hydratis: a brand committed to better understood hydration
Created in 2019, Hydratis has set itself the mission of democratizing more effective and conscious hydration.
Faced with the observation that nearly 4 out of 5 French people do not drink enough water (IFOP study for Hydratis, April 2025), the brand develops solutions adapted to daily life but also to specific situations such as exercise, heat, travel, or altitude.
Hydratis tablets combine electrolytes and trace elements, including magnesium, potassium, zinc, and manganese, to support hydro-electrolyte balance and optimize water absorption.
Present in over 11,800 pharmacies and used by several million people in France, Hydratis continues its on-the-ground commitment 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 the cold. It simply becomes less noticeable.
Between altitude, dry air, increased ventilation, and decreased thirst sensation, the mountains are an environment where fluid balance is put to the test.
Integrating a regular hydration habit, adapted to your activity level and altitude, is a decisive 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, both summer and winter.
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