Skin rash

I didn't used to do that, but maybe since last year? And it has to be that way.

Is it eczema on my thighs only during the summer, appearing red and creeping up? Why does this happen? Is it because of sweat?

I think I feel it coming up after working out intensely.

So I always turn on the fan when I exerciseㅠ

I also visited the hospital, and they just gave me ointments, oral medication, and injections like this, with no other comments. Fortunately. Once I leave the hospital, it feels so much better.

I'm glad I sank... but why has my skin changed?

I'm curious if my constitution gradually changes as I age.