I have always had to buy pants big enough to fit my thighs and bottom, which means the pants are too big in the waist. A saleswoman once told me to stop exercising so that I could fit into a smaller size. Never went to that shop again. (At the time I weighed about 125 pounds, and I am 5 foot 9. Have not seen that weight in a while.)

With biking my glutes are an asset, especially once my lungs get a bit stronger!