Allyson Felix, the most decorated female track and field Olympian of all time, will retire at the end of the season.
The 36-year-old American has won 11 Olympic medals, including seven golds, as well as 13 world titles.
She competed at her fifth and final Olympics in Tokyo last summer.
“As a little girl they called chicken legs – never in my wildest dreams would I have imagined I’d have a career like this,” said Felix.
“I have so much gratitude for this sport that has changed my life. I have given everything I have to running and for the first time I’m not sure if I have anything left to give.
“I want to say goodbye and thank you to the sport and people who have helped shape me the only way I know how – with one last run.
“This season isn’t about the time on the clock, it’s simply about joy. If you see me on the track this year I hope to share a moment, a memory and my appreciation with you.”
Felix has won four Olympic golds in the 4x400m relay, two in the 4x100m relay, and one in the 200m.
BBC