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Lakers shooting guard Kobe Bryant reportedly missed his informal practice session this afternoon because of "flu-like symptoms," and it's not yet known whether he will play in tonight's game against the Indiana Pacers.

Although the common cold and influenza are both respiratory viruses that can often get mistaken for one another in the early stages, Dr. William Schaffner, chairman of preventive medicine at Vanderbilt University, said whether people could complete a workout was a good indicator of which virus they had.

"With a cold, actually going to the gym will frequently make you feel better," said Schaffner, "If you try to exercise with influenza, it makes you feel worse."

For a patient with a cold, a good workout will boost adrenaline and open up nasal passages, Schaffner said. A flu patient will probably feel too weak to attempt physical activity.

Click here to read about flu-fighting superfoods and recipes.

Michael Jordon became possibly even more famous after he played what would become known as "the flu game" in 1997. Despite flu symptoms, Jordon finished the game scoring 38 points for the Chicago Bulls, including a three-pointer in the final few seconds of the game, bringing the total score to 88-85, according to NBA.com.