Kersploosh! There's nothing quite like the feeling of jumping into a cool pool on a hot day, is there? As you sink down into the water, your whole body is refreshed at once.

Of course, if you swim on a sports team, the water might not seem quite as refreshing as when you're just having fun. When you're swimming laps or racing other swimmers, swimming becomes a strenuous form of exercise.

As you swim lap after lap, you might be surprised to find out that you get thirsty. Kind of weird, huh? You're surrounded by and immersed in water, yet you are parched on the inside. What's up with that?

What you're experiencing is dehydration. That's a big word that simply means your body has lost a lot of water and needs more. But how can your body lose water…when you're IN the water?

Swimming is tough exercise and your body sweats — in the water — just like it would if you were running or playing another sport. Since you're in the water, though, you usually don't notice that you're sweating. As a result, you may not realize you're getting dehydrated.

As your body sweats when you swim, you need to replace that water. Your muscles communicate with your brain, which tells you that you're thirsty and need to drink. Just like a runner that needs water to perform at the highest level, swimmers need to keep hydrated, too.

It may seem strange to get thirsty while you're surrounded by water, but it makes sense. The body doesn't absorb water like a sponge. So even though you're immersed in water, your insides — where you need the water to function — isn't getting any water from the pool. To fuel your body properly, you need to drink fluids!

Just don't take a gulp of pool, lake, or ocean water! You can get sick easily by drinking water from those sources. Instead, go to a water fountain, drink bottled water, or use sports drinks like you would in other sports.

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