Is it possible for one with ctd/lupus to get butterfly rash with aerobic exercise even indoors? i get it in the sun, but also indoor tough workouts.

Yes: The malar rash associated with lupus can worse or appear during sun exposure due to worsening of the small vessels inflammation. The same explanation for aerobic exercise malar rash worsening. Treatment are uva and uvb sunscreen lotions with spf of no less than 30, steroidal creams to reduce inflammation, some data show useful vitamin e oil, olive oil, cod oil. Stay hydrated all the times.

Possibly from lights: Possible uv exposure from fluorescent lights, but ? Also from heat?