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How does spring fever affect people differently?

A phenomenon that makes people feel more energized and need less sleep may sound like a myth, but some experts say it exists.

It's called spring fever, but not all of the symptoms are pleasant. Spring fever is poorly defined, because it does not exist in any official classification of emotional disorders.

However, Dr. Norman Rosenthal, clinical professor of psychiatry at Georgetown University Medical School, said a common misconception is that spring fever doesn't exist.

"As someone who has studied the effects of the season on human mood and behavior for 40 years now, I can attest that it is very real," Rosenthal said. "...The enormous changes that occur in nature in the spring induce in people not just one type of 'spring fever.'"

The changes include a rapid expansion of days, trees and flowers bursting into life, as well as the fresh start that spring brings.

But, Rosenthal said, these changes in spring affect people in different ways. Some may have increased energy, be cheerful and motivated and need less sleep.

Wildflowers in meadow

Wildflowers in a meadow during spring. (Jupiterimages/Getty Images)

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Others can experience a mixed state that includes elements of the winter doldrums left behind such as a poor mood, sluggishness and more. When those symptoms are accompanied by increased energy, it can lead to irritability, according to Rosenthal.

Some could feel like they need less sleep while others feel lethargic.

Physiological reactions are also a possibility. For example, people want to get into shape for wearing bathing suits during summer.

A female runner gasping for air after running hard

Tired runner taking a rest after running hard on beach. (lzf/Getty Images/iStockphoto)

According to Web MD, a lot of heart attacks happen in the springtime because people start exercising without easing into it.

"Often people who are subject to mood changes other times also experience spring fever, but it may also occur in those allergic to spring pollen," Rosenthal said.

Many changes take place in the spring because of the rapid increase in sunlight and temperature. Pollen may cause the release of immune substances that make people drowsy and irritable.

"It is pleasant to have increased energy, but the word fever conjures up something that doesn't feel altogether enjoyable..." Rosenthal said.

Rosenthal has tips and helpful information on his website to help combat spring fever and seasonal affective disorder.

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