What hamsters are more active and get sick less?

Question
All the hamsters in the pet stores that I went to were sleeping during the day.Are all hamsters like that? Do they they ever use the excersise wheel? What hamsters run around the most?
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-----Question-----
I want to get a pet hamster, but don't know what kind I should pick?  I want one that is active and doesn't get sick much. I thought about a Blueberry Dwarf Hamster, but I don't know if they are active.  My mom thinks about getting a gerbil but I don't know if any fit this category, and if so what kinds. Also, should I buy 1 or more?
-----Answer-----
If you want a hamster you can hold and interact with, don't get a dwarf or a gerbil, they are much too small and quick, and don't like to be held quite as much. They are more "look at" animals. Get a syrian, the big guys. Your pet store may call them "golden syrian" or "fancy" or "long hair/short hair" hamster. They come in many colors, and they all look pretty much the same, a long body and tiny legs. Don't get a black bear or teddy bear variety until you've had experience with hamsters, they can get to be a bit mean, (trust me I own one, he's still jumpy after a year). Hope I've helped!

Answer
ALL hamsters will sleep durring the day. Hamsters are nocturnal by nature, meaning they are active at night alot more. Hamsters do like their wheels, I suggest a metal one vs a plastic one. Don't get discouraged if they don't use it at first, they have to learn to like it. Most syrians are active about the same.