It's something that tends to bug those who aren't 'keen' on the secret identity, even though, visually, Christopher Reeve and others have made it work: how is Clark, the mild-mannered reporter, so jacked.
And the characters themselves (those not in the know) have wondered about it.
We had it back in '86 with the reboot and Lois using Clark's weights and commenting on how light they are; we had it in '93 (in Lois & Clark) with Lois wondering how Clark can eat like an eight-year old and look like Mr Hardbody; we had it after Final Night when a Daily Planet maintenance staff member said to Perry that he didn't know Clark had such a build on him (and I think there was some comment by Cat Grant over in Supergirl, too).
I've often joked that it's because Clark is anxious and knows that exercise is good for mental health, so I couldn't help but chuckle when they slipped it into The Good Place.
Chidi is Clark (others on this board have commented on that, too), and he is jacked. The creator of the show had previously said the same thing but now it's in the show and is official.
And it works for Clark, too. Totally. And the SI-scoffers never need to say anything again (about his body... they will always talk about his face).