I see the phrase “walked leisurely” with surprising frequency. It falls under more than one category of poor word choice: it uses an unnecessary adverb and uses two words where one would do. Instead of “walked leisurely,” any of these words would work better:
Stroll: to walk in a leisurely or idle manner.
Amble: to walk slowly in a free and relaxed way (generally carries a more aimless and leisurely connotation than stroll).
Saunter: to walk along in a slow and relaxed manner (implies a cockier attitude than stroll or amble).
Meander: to walk slowly without a specific goal, purpose, or direction.
Ramble: to move aimlessly from place to place or to explore idly (usually indicates a more widespread area of movement than meander—for instance, you might meander around a store or maybe a town, but ramble around a country).
This seems to be a common phenomenon with verbs of motion—rather than finding one word that fits a character’s movement best, writers use a common verb with an adverb. Here’s some other examples that I’ve seen:
“Ran hard”—usually better as sprinted
“Jumped up and down repeatedly”—bounced or hopped.
“Quickly moved out of the way”—dodged, evaded, or sidestepped.