Hydration
During training, swimmers naturally generate heat leading to a rise in body temperature. A rise in body temperature can be both detrimental to performance but also contribute to fatigue. Our bodies attempt to compensate for rising temperature by sweating. When we do not consume enough fluids during training to compensate for these sweat losses, dehydration can quickly occur.
Knowing how much fluids have been lost is important in rehydrating the body. One way to monitor hydration levels is to use an urine chart: