The context of the following conversation is Kendall wanted a challenge, so Kendall entered a marathon.:
Kendall says I signed up for the marathon today..
The friend responds Wow, that takes a lot of guts! I didn't even know you were a runner..
Kendall responds I'm not. I only signed up because I wanted to challenge myself..
The friend responds In that case, you've got your work cut out for you!.
Kendall responds I know, and I only have three days to train for it..