>>1413042this combo is what i would suggest
get the leggings from a good outdoor store, polyester
make sure the shorts have a drawstring and you have total free movement in them. I have some that are cotton and cost $10 from a cheap clothes store (like in the pic), and some nylon ones from an outdoor store that cost $50. The former wears out quicker and gets sweatier but they're both good for cycling.