If you ever want to have a kid that is genetically doomed to never be able to fit their thunderous thighs into the skinny jeans of tomorrow-land, make sure that you craft that baby with another cyclist.
Their childhood will a string of misery and alienation as all the other youths go galavanting about the playground in their tiny, skinny jeans and your kid will sit there, friendless, in their relaxed fit jeans. Then one day, they will discover that their curse is a gift when they stomp down on a set of flat pedals and their bike bucks like a bronco backlit by the setting sun. Oh, and the joys will come flooding in to fill the voids carved by years of being an outcast. The child will work hard to become the best their thunder thighs can be, riding drills late into the summer evenings.
Eventually the child will take up racing, quickly realizing that cross country racing is pretty much for assholes, enduro racing is just what cross country should have been all along, gated racing is but an echo fading in the past, and choosing to race downhill. The child will struggle for years, advancing through the local and then national ranks.
But then something will happen. The child will travel abroad to race in the big leagues of the World Cup. And every skinny little French person, regardless of gender, will best their time down the mountain despite the gift of thunderous thighs, which have carried them all the way to this strange land of rain and generally shitty food. Why- they will ask. Why?
Because your parents were cyclists and had sex. But this alone is not enough. The child, now all grown up with innocence and dreams smashed, must figure out what to do with their life and their thunder thighs.