I used to do the same every track meet.
I think it was a mix of me being nerved up and too many complex carbs+fibers the day before, but every day of a track meet I would liquid piss shit like 3-7 times before my race.
in fact, I won city finals for steeplechase last year and right as I was booking it over the last water pit to beat my pm, I had a wee squirt. not enough to get past my cheeks, not enough to slow me down either, but the 30min walk home after my race was the most uncomfortable walk of my life. when I got in the shower I had never felt such a burning sensation on the outside of my butthole.
I will never forget that day.