A 12-year-old girl accidentally ran her first-ever half-marathon, giving her mother a major fright for more than an hour, Democrat & Chronicle reports.

As part of last Sunday's Rochester Regional Health Flower City Challenge, LeeAdianez Rodriguez had signed up for the Wegmans Family 5K race. As her mother dropped her off at the location, Rodriguez joined thousands of runners at the starting line on the Broad Street Bridge, not knowing that she was in the wrong group of marathoners.

Apparently, the 5k group was scheduled to start on the same bridge 15 minutes after the distance runners set off.

According to The Guardian, the girl realized her gaffe about halfway through; however, she decided to go on and decided to finish.

"About the fourth mile, I asked a woman I was running with how long it was and she said about 13 miles. That's when I realized I think I was running in the wrong group," Rodruiguez told News 10 in an interview.

"I kept going, I knew after a while I was in the half marathon and I was like 'I'm going to finish this. I'm going to keep going,'" she added.

Thus, instead of running 3.1 miles, she ended up running with the half-marathoners on the 13.1-mile course.

Despite having only two months of training - following her big run with a nap, large meal and a hike - the sixth-grader ended up finishing the race with a time of 2:43:31.

That gave her 1,885th place out of 2,111 runners, but made her one of the youngest to pull off the feat, Fox 8 notes.

"She just wanted to finish the race," her mother Brendalee Espada told the Democrat & Chronicle. "Two hours after I started looking for her, I see that one of the officers found her. And I see she has a medal."

As a tip to those who want to run a marathon, here are some guidelines from Coach Jenny Hadfield of Active.com:

  1. Taper your training
  2. Set healthy expectations
  3. Go with what you know
  4. Review the course
  5. Avoid unnecessary stress
  6. Run for the finish rather than the time
  7. Keep in mind few power words or phrases
  8. Perform head-to-toe form check
  9. Dedicate a mile to a person or cause
  10. Walk a minute every mile
  11. Celebrate and recover