The antonyms for the phrase "reaches up" include words like reach down, stoop, slump, sag, droop, crouch, and crawl. These words all suggest a posture or action that is opposite to reaching up, indicating a downward movement or a lack of effort to move upwards. Reach down suggests reaching lower, possibly for an object on the ground or a lower shelf. Stoop and slump imply a bending or hunching over, while sag and droop depict a hanging or sinking motion. Crouch and crawl indicate a more deliberate and controlled movement, but still in a low or grounded position.