The phrase "making inert" means to render something inactive, powerless or ineffective. Antonyms for this phrase can be "activating", "energizing", "stimulating", "invigorating", "awakening", "rousing", "vitalizing", "reviving" or "animating". These words denote the opposite meaning of "making inert" as they refer to actions that bring things to life, or make them lively, vigorous, productive and dynamic. So, while "making inert" implies something that is static or stagnant, these antonyms suggest energy, movement and progress. By using the opposite words, one can convey a positive and vibrant meaning, rather than a negative and stagnant one.