If you're prone to muscle cramping, muscle spasms, charlie horses or the like, the chances are that you are dehydrated. During a volleyball match, your muscles need fluids to operate powerfully over time. If you don't give it to them, they revolt.
Another test of hydration is the color of your urine. If your urine is light to clear in color, you are well-hydrated. If it is very concentrated and a deep or dark yellow, you are not very well hydrated. Keep in mind that if you are taking a multi-vitamin, your urine may be more concentrated with all the extra nutrients the vitamin provides that did not get absorbed by the body. But you should still strive to keep the color light.
Other signs of dehydration are dizziness, nausea and disorientation which can also imply heat exhaustion or heat stroke. This is fairly unlikely for indoor volleyball, but if you're playing outside in the summer, this can be a major factor and it is extremely dangerous. See a doctor immediately if you feel these symptoms or notice them in a teammate or opponent.
You can tell if you are dehydrated by:
- The color of your urine - it should be light to clear in color if you are properly hydrated
- Your muscles - cramping and spasms are signs of dehydration
- Your weight - weigh yourself before and after exercise. Any weight lost can be attributed mostly to fluid loss. Within the two hours after the end of play, drink 20 ounces of water for each pound you lost.