"The plantar fascia is in a relaxed position when you're sleeping, " says Jacqueline Sutera, a podiatric surgeon in New York City.

CNN: Why your feet hurt

What causes it: Inflammation of the plantar fascia, a thick band of tissue that runs along the bottom of your foot from the heel to the toes.

CNN: Why your feet hurt

More than 2 million Americans suffer from debilitating heel pain stemming from inflammation of the plantar fascia, a fibrous band of tissue that supports the arch of the foot.

FORBES: The Big Hurt

He was ruled out for the third time in four games after an exam Thursday of his strained heel also revealed a plantar fascia tear in his right foot.

WSJ: Nuggets beat Nets to win 18th straight at home