The phrase "laid up on" typically denotes an individual who is restricted or incapacitated in some way. Hence, its antonyms refer to action, movement or freedom. Words like "active," "up-and-about," "mobile," and "working" are some antonyms of "laid up on." These words indicate that the person is free to move about and perform tasks without any physical hindrance. Other antonyms include "healthy," "fit," "well," and "sound." These words suggest that the person is in good physical condition and can carry out tasks without any difficulty. To sum up, the antonyms for "laid up on" describe a person who is active, able-bodied and living a normal life.