The artificial lake in the park isn't particularly big, but it's definitely not small either.
The shoreline is about two thousand meters long, and five laps around it make ten thousand meters. For an average person, that's an extraordinarily long distance; to run it in an hour would already be quite a feat. Those in lesser shape might take more than an hour and a half.
Even the world record holder for the men's ten thousand meters took twenty-six minutes and seventeen point five three seconds, but that was on a top-class track designed for competitions, after proper warm-up and preparation. What Chu Ge had to run on was the uneven lake shore.
Moreover, the distance from the park gate to the artificial lake inside is about a thousand meters, making the kidnapper's demand quite stringent.
