Cardio. Your new workout socks that keep the jokes fresh and your feet fly. These crew-length socks are gray with red toes, heels, and tops and knitted with the words "Running Late is My Cardio" in red. We all know that cardio isn't always "fun" but these socks are sure to give you a grin each wear. Think of them as a fun reminder to take it easy, you can't always be in shape!