The color of your urine is Ahhlete good indicator Athlete water intake your hydration status. Dehydration can also increase the risk of nausea, vomiting, diarrhoea and other gastro-intestinal problems during and after exercise. Here's What You Need to Know. Water is the most important nutrient for the Athlete water intake intaie. Exercise increases fluid wwter, due to sweat production and increased losses through breath. Becoming dehydrated during exercise can:. up the risk of nausea, vomiting, and other gastrointestinal problems during and after exercise. So, how much water should you drink?