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SATURDAY, July 12 (HealthDayNews) -- A summer workout can leave you feeling great -- as long as you don't let yourself get dehydrated.

The combination of heat, humidity and activity can cause your body to lose water and essential elements, leading to the risk of kidney problems or even death, says the University of Michigan Health System.

If you're working out hard enough, you can become dehydrated any time of the year. However, the risk of serious dehydration increases when temperatures go above 75 or 80 degrees F and there is high humidity.

You may think you just need to drink when you feel thirsty. Wrong. Thirst isn't a reliable indicator. You should be drinking enough water or a balanced salt solution (for example, Gatorade) before, during and after any workout.

Signs that you're not getting enough fluids and may be becoming dehydrated include an uneasy feeling and a noticeable drop in your energy and performance levels. You may also get a headache and body aches.

If you ignore those warning signs and don't drink enough to replenish your body's fluid levels, you could be in danger. Your body temperature may rise and cause your perspiration (which acts as your body's cooling mechanism) to slow down or stop. You may then pass out.

Water and balanced salt solutions are the best way to replenish body fluids and elements. Don't drink soda or juices.

Coaches and parents of young athletes need to ensure the youngsters drink enough while they're playing sports.

More information

Here's where to learn more about sports and dehydration.