I know it's lame to ask, but....

[talulah gosh]

There is a riff I have never understood: at 41:41 (looking up at guy crawling through duct work), Mike says, "This seems like a great workout."  Bill and Kevin respond by saying "**** you" and Mike replies that he gets that a lot.
Are they berating him for mentioning exercise? I'm so confused.
Also, this emoji is not relevant, but I like it.