Hi ladies - throwaway since my boyfriend knows my account

I have been with my boyfriend for just over a year now, and we’re both in our mid twenties. He has proven to be a man of character and I could see myself marrying him. The most prominent point of incompatibility in our relationship however is the amount of effort we put into our appearances.

I can communicate to him about every other issue, but I suddenly don’t know how to talk to him when it’s about how I think he could dress better, or how I would prefer him to put on some muscle.

I take care of my body and dress better than every occasion requires, so I just would prefer him to do the same. I know that one’s personal style and exercise regimens are very personal things though, so I don’t know how to bring this up or communicate this without hurting his feelings.

I realize I may sound nit picky - but I think these factors lie at the core of my attraction to him, so I would like to find a way to maybe encourage him to work on himself, like I work on myself, so we can both be our most attractive selves for each other

Have any of you been in this position before?