The code/law for elementary school through grade 6 states: 135 minutes of moderate to vigorous activity.
I know that in one school district with very a strong fine arts director and district support for fine arts that they were able to include structured movement/dance during music class in those 135 minutes.
The TEA code does not say "PE" for 135 minutes. Most elementary PE teachers read it as 135 minutes of required PE and tell that to their principals when setting up schedules. For most schools that would wind up being 3 days of PE for 45 minutes. In the district that I know about PE was 2 days, music 2 days and art 1 day with 45 minute classes. Because the music teachers were Off trained, which uses a lot of movement they were able to move the other 45 minutes of "physical activity" into the music curriculum during the 2 days of music.