Hyponatremia is typically caused by consuming too much water which effectively flushes critical electrolytes from your blood. One way to reduce your risk is to consume a sports drink instead of water. A good sports drink such as our e-Fuel product provides electrolyte replacement in addition to rehydration and sustained energy. While it is wise to use a good sports drink (or e-Gel and water), it is important to note that if you drink too much of any fluid you increase your risk of hyponatremia. Your fluid-replacement plan should be designed to minimize loss of body weight so that you avoid dehydration during exercise but prevent weight gain from excess hydration. A good way to gauge your fluid requirements is to determine your hourly sweat rate. To do this, you can calculate the difference between your weight gain or loss during exercise and the volume of fluid consumed. For example, if you lost 1 pound (16 oz) during a one hour run and you drank 16 ounces during the run, then your sweat rate was 32 oz/hour under those conditions. Therefore, you should try to drink 32 oz each hour during similar-intensity training and racing. In this example, drinking 8 ounces every 15 minutes would do it.