The Norwegian language, like English, uses the “s” ending as a possessive, but without the apostrophe. For example “the dog’s food” becomes “hundens mat.”
Norwegian, like German, combines lots of words together into compound words. For example, the Norwegian word for sandwich is “smørbrød”, a combination of the word for butter (smør) and the word for bread (brød).
These two key facts result in most Norwegians probably reading this Spotify advertisement as “workout’s best songs” and not “training shits”. But it gets me every time.