In my experience, skinny men tend to prefer girls who aren't too thin. Think it's an "opposites attract" thing.
I feel like I in a way get to see more of his body when he is thin, like cheekbones are clearer, hipbones, collarbones... This sounds a bit sick lol, of course I want him to be healthy as well. I just think skinny men are more attractive.
The problem I've had dating athletes is that they are too picky about what they eat. That has to be one of the biggest turn offs in a man lol, I want someone who doesn't worry too much about his body and doesn't have to. This one guy (he was studying to become a gym teacher) I went out for coffee spent the whole date talking about what great shape he is and how he never eats anything unhealthy. Geez, that's great, can I go now?