Alas, no "Kate Hudson" was listed in the official results of the LiveStrong 5K. Yes, I literally searched her name - you never know! Katie Holmes was listed in the ING NYC marathon results, after all. (Although, I guess there is some suspicious activity there.)
I was starting to wonder if I actually saw Kate Hudson and then I noticed this photo from the event:
Yep, that is definitely who I saw at the 5K. Very cool!