Hi Anna!
Welcome back to the Disney Parks Moms Panel. I am so excited for you to run the
Disney Princess Half Marathon, it was my first runDisney race and still one of my favorites to this day!
Check out time at the Walt Disney World Resort hotels is 11 AM, so depending on your running pace you may not need extra time! If you think you may, let the Cast Member at the Front Desk know when you check in that you are running the race and would like to request a late check out. Based on availability and their booking capacity they may let you know then whether or not they can accommodate your request. At other times, they may ask that you check with housekeeping the day before you leave. They truly try their best to accommodate all their Guests so I'm sure they'll do what they can to make sure you're able to shower off some of the pixie dust you collect during the race.
If for any reason they are unable to extend your check out, most resorts have showers available in the restrooms near the pool facilities for you to be able to freshen up. The bellhop service will gladly hold your other luggage for you so you only need to take in the necessities.
I hope you have a magical race and please let me know if you have any other questions!
-Lindsey