The antonyms for the word "walks up down" are many. The most common opposite words are run, sprint, hurry, dash, scamper, dart, bolt, rush, gallop, and jog. These words signify movement at a faster pace or with more energy. In contrast, some of the slower antonyms may include saunter, amble, stroll, wander, meander, and trudge. These words may describe a less energetic or leisurely pace. Additionally, some antonyms may portray movement that goes in other directions, such as climb, descend, descend, or ascend. All in all, choosing the right antonym for the word "walks up down" depends on the context and desired pace of movement.