NEW YORK – The pain starts when you wake up – a stab in your heel when you get out of bed, an ache when you put weight on your foot.

The condition is persistent and common. According to the Centres for Disease Control and Prevention, at least 10 per cent of people get it.

Plantar fasciitis, an inflammation of the tight band of tissue on the bottom of your foot, can happen to anyone, said Dr Eveline Tan, a podiatrist at Northwestern Medicine, but it occurs more frequently in people who are on their feet for long periods of time.

“It’s probably more common than most people think,” she said, noting that she has seen a resurgence of patients with the condition as more people have been returning to post-lockdown life.

Golfer Tiger Woods posted on Twitter last November that he withdrew from a golf tournament because he had developed plantar fasciitis in his right foot, making it difficult to walk.

The condition can be agonising, but it is generally temporary, and there are treatments and preventive steps people can take to ward it off. Here is what you need to know.

What causes plantar fasciitis?

The telltale sign of plantar fasciitis is pain in the bottom of the heel, said Dr Nirav Pandya, a sports medicine specialist at the University of California, San Francisco.

That pain becomes pronounced after lengthy periods of inactivity. People with the condition feel their feet throb when they step out of bed after a night’s sleep or when they get out of the car after a long drive, Dr Tan said.

Doctors are not sure about the precise mechanisms that cause plantar fasciitis, said Dr David Walton, an assistant professor of orthopaedic surgery at the University of Michigan. But the condition is common among athletes and in people who suddenly change their levels of physical activity, such as those who get back into working out after an injury or people levelling up the distance as they train for a marathon.

It is also common in people who sit at a desk for long periods of time, he said. Even a small change in the amount of strain you put on your foot can lead to plantar fasc...