Feasibility of Using the Gatorade Sports Science Institute (GSSI) Labs App for Hydration Related Outcomes

This study is testing a smartphone app called the GSSI Labs App to see if it can reliably track hydration levels using data from wearable devices like smartwatches and activity trackers. The goal is to determine if the app is a practical tool for monitoring fluid balance in everyday life. **You may be eligible if...** - You are between 18 and 65 years old - You own and wear a compatible activity tracker daily (such as an Apple Watch, Fitbit, Garmin, WHOOP, Oura, Polar, or Withings) - You own a bathroom scale - You are able to drink 600 mL (about 20 oz) of water as instructed - You are willing to avoid alcohol for 24 hours before the study session - You can read and write in English **You may NOT be eligible if...** - You are currently in or recently participated in another clinical trial (within 30 days) - You or an immediate family member works for a company that competes with Gatorade products - You are pregnant, planning to become pregnant, or breastfeeding Talk to your doctor to see if this trial is right for you.