Gallo picks "relax as a noun" as a sample of Italians using English wrongly.
But the American language has largely undifferenced nouns and verbs, which is fine by me as long as clarity is preserved. (I just did it on purpose-- undifferenced-- with no ambiguity. So why hang onto an aging grammatical rigidity, only recently applied in this case?)
Follow the poets, not the classroom English teachers like Gallo. As William Blake put it, "Damn braces, bless relaxes."