Lauren Huddleston, 28, made an abrupt U-turn on the trail and was hit by an oncoming bicyclist in the 3100 block of Routh Street, according to a police report.
Police said Huddleston was listening to music and may not have heard the cyclist coming.
The jogger and the cyclist were both hospitalized after the collision. The bicyclist was released from the hospital with a broken collarbone.
Huddleston remained in intensive care at Baylor Medical Center on Friday night.
The Friends of the Katy Trail hopes the tragedy serves as an important safety reminder to the thousands of people who use the trail every day.
"It's a rough lesson for everybody," said Robin Baldock, executive director. "We have to watch out for each others' safety and be considerate of others on the trail."
"Our heart goes out to the families and all the people who were involved in this incident," she said.
Mark Simon, a personal trainer in Dallas who spends several hours per day on the trail, said such incidents are "going to happen."
"It gets clustered, and you have to be cognizant that people aren't doing what you think they are going to do," he said.
Dallas police said they will not file criminal charges filed in the case, calling it a tragic accident.