All the other kids with the pumped up kicks,
You better run, better run, outrun my gun.
All the other kids with the pumped up kicks,
You better run, better run, faster than my bullet.
So I admit, while I basically knew what this Foster the People song was about (kid contemplating shooting spree), I had to look up "pumped up kicks" in the urban dictionary. Means expensive shoes according to the info I found.