I'm certainly no expert, but most of perek 4 in Hilchos De'os seems like it doesn't fit with the rest of Hilchos De'os. It's all about maintaining a healthy body. Any ha'aros on why it's there? Am I misunderstanding it? Thanks in advance!
1See ibid. 3:2-3, which explains how "all of one's actions should be exclusively in order to know Hashem," and that this includes maintaining a healthy body in order to serve Hashem. Chapter 4 is a direct continuation of that.– MeirJun 26, 2020 at 0:55
1This is the same view expressed in Kitzur Shulchan Aruch, siman 32. Thus, it should be understood that this view of Rambam (a Rishon) was accepted amongst later Acharonim.– Yaacov DeaneJun 26, 2020 at 3:06