Morning fitness outdoors makes me empty my bladder fast

I just arrived at a secluded place and I change in the car putting on my new jeans tights. But.. I made a mistake. I forgot to pee when I left home so.. jumping up and down for my exercises makes me want to pee, but.. I just sit on the cement block and pee right there hoping no one passing by would see me. But since I wet myself so well I have to change. My luck I have a spare pair of panties. PA209