Someone at work told my friend that I look like a "bike racer". I'm pretty confused as to what that could mean?

It suddenly made my feel like I don't have a feminine enough body. I mean it's true. My mother bitterly calls me a man every time I dress up for work because I'm pretty flat front and back and I'm thin and lean and tall. I just don't look feminine in work suits. And that makes me sad. I could wear dresses to work too but that looks too extra.... Too eye catching. Probably not professional. But I wasn't expecting this from a coworker.