The doctors told him he couldn't walk, he's a coach today

This disease reduces the flow of blood to a femur, causing bone to collapse.

Symptoms include pain in hips that increase movement in knots. It affects one in 9,000 children, according to data, and doctors still do not know the real cause of the disease.

Zachary had to give up training his favorite sport, lost school classes, and spent two years in a wheelchair.

Despite severe pain, he has learned how to stay and walk without help, and he works as a master teacher, reports Metro.co.uk.

It was extremely painful, or rather, painful. I can't explain the pain,” he said.

The doctors told him that he would not be able to walk without feeling pain.

Zachary started practicing on foot every day. He saw positive results when he started walking out of his chariot alone.

By the time he turned 16, his condition had improved greatly and began to exercise in the gym. There he discovered a passion for the gym.

It was a miracle to get out of a situation where I could barely walk, to compete in school,” said Zachary.

He says he thought he'd never be able to do the coach's job so they wouldn't laugh at him, because he's different.

Doctors said one of his options for recovery was a complete replacement for the thigh.

This master coach decided to reshape his loins five months ago.

He shares his story through his profile in the Instagram to inspire other people never to give up their dreams but also to help children cope with this invisible disease.