Hello Alicia, and welcome to planDisney!
As a past
RunDisney race participant, I have thoroughly enjoyed the time I have spent at the races and in the theme parks after the fact.
To answer your question, the RunDisney race will not affect your theme park reservations; the theme parks will open at the times noted. The only issue I could see is traffic leading to the theme parks, but in that case, leaving a little earlier will help. If you plan to utilize the
Walt Disney World Resort transportation system, it starts about 45 minutes before the scheduled opening.
Remember to make your theme park reservations using the
Disney Park Pass System and have your theme park tickets linked to your
My Disney Experience account.
We will be here if you have additional questions. Let us know how we can help.
Have a magical experience!
Raquel