The phrase "most dead beat" implies extreme exhaustion or weariness. Its antonyms would therefore include words such as lively, energetic, refreshed, invigorated, and rejuvenated. Other possible antonyms could be vibrant, lively, sprightly, or flourishing. These words all connote a sense of vigor and vitality, the opposite of the sluggishness suggested by "most dead beat". Such antonyms describe a feeling of being alive, and invigorated, as if one has a sudden burst of energy. These words can be useful in a variety of contexts, whether discussing physical exertion, mental fatigue, or emotional depletion.