How do I prevent Heat Exhaustion?

Question:

I tried out for volleyball yesterday and about 30 minutes into the practice I started feeling awful so when I got home I looked up my symptoms and it turned out that I had heat exhaustion. I have tryouts again today and I don't want it to happen again today because I couldn't perform my best yesterday because of it. I didn't say anything because I wanted to impress the coach but I couldn't seem to do my best. These were my symptoms
excessive thirst
nausea
dizzyness/lightheadness
I also didn't have any water except the water fountain water which made me feel worse because it was warm
so what can I do.

Answers:
continue to hydrate yourself ahead of time. Drink plenty of water, and also re-hydrate using gatorade to replace those electrolites that water cannot replace. Remember, when you feel thirsty that means you are already dehydrated, but that doesn't mean that you won't feel thirsty while working out. Don't eat too much, but have some carbs for energy. If you drink too much water you can experience nausea also. Stay in the shade on breaks or when possible, and when needed rest. Just because it is the first day of practice doesn't mean it is okay to push yourself to the point of heat exhaustion or even worse a heat stroke. Be honest with yourself and your coach when you need a break. Good luck.

Take a water bottle with you ,wear loose fitting cloth and try to find a place that is cool when your not playing ,heat exhaustion is a very serious situation,I mean real serious

First off heat exhaustion is not a dire emergency, heat stroke though is. Like the first guy said, you need to keep yourself hydrated; thats number 1. Water is great for this, and gatorade or other sport drinks are okay, but don't rely on just those. Keep sipping throughout practice. Shade and fluids. Rest if you start to get cramps, and then sports drinks would be a good idea. Even warm water is better than no warm. When the temp is high it's important to keep up on the liquids. You must be real careful, especially if it is also humid as this is when people most often get heat stroke. Heat stroke is when your body looses the ability to regulate your internal body temp. Your temp can suddenly soar to well over 105 and begin to fry brain cells.
I was unfortuate enough to run a call one hot humid day when our local AAA hockey team had tryouts, and lost 2 players to heat stroke, and a third nearly died. Was quite tragic.
Your sunburn probably added to your dehydration, and thats something most people overlook. Good luck on the team!

How do I prevent Heat Exhaustion?

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