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Athletes have been guessing how much water they need to drink for decades, and getting it wrong, with significant consequences to performance and safety. Now, a new technology has been developed at the Harvard School of Engineering, with the world’s leading hydration experts and physiologists. Nix is developing a single use hydration sensor that informs athletes’ hydration strategy: when to drink, what to drink, and how much to drink.

Although the initial product is for endurance athletes including runners and cyclists, future uses that the system is being adjusted to is first of all – millitary units. Other than that also team sports and manual laborers.

Today, there is no better method to determine a hydration status in real-time other than thirst and estimated sweat rate, which are notoriously poor and delayed indicators of fluid needs. Even mild levels of dehydration can initiate a cascade of physiological changes that impose cardio-respiratory stress, compromise thermoregulation, and significantly impair physical and cognitive performance.

According to, the Nix sensor detects changes in sweat composition in real-time. This enables athletes to optimize their hydration during a workout, race, or game. The patch with the sensor sends visual cues to the user to take action with any change in hydration status. It also tracks the composition of sweat that an athlete is losing, and recommends water or an electrolyte drink for replenishing. Individual fluid needs vary, and the Nix biometric hydration sensor enables athletes over time to better understand their bodies and optimize their personalized hydration strategy.