Loki was, in fact, pretty much the thesaurus' favorite antonym for 'bulky', after all!
More thoughtfully, Loki considered Thor's jest. "Longest bout I ever had, back in university, was about three hours of fighting, with a few water breaks tossed in – none of them were longer than a minute or two, but for completely non-stop fighting I don't think it was every longer than twenty minutes or a half hour, at most."
Oh, look, Sif's office! Jotnar perked up, woofling happily at the sight of his person again, and then got thoroughly petted for his troubles.