Nick Symmonds has always considered himself a businessman first and an 800-meter runner second.

“I’ve never really considered myself a runner,” he said. “Running was a business of mine” and “a great way for me to market products.”

In a recent interview, Symmonds, 33, announced that he would retire from the track after the 2017 outdoor season. He will leave the sport as a two-time Olympian, a six-time United States outdoor champion at 800 meters and a silver medalist at the 2013 world championships in Moscow.

He will also leave as perhaps the most outspoken, polarizing and essential American track and field athlete of the past decade. As a runner, his preferred style was to sit and kick. As an activist for athletes’ marketing rights, as well as an advocate for gay rights and gun control, he operated from the front, a loud, bold provocateur.

His greatest compliment probably came from the sportswriter who once called him “Team USA’s official pain in the butt.”