不要太累用英语可以说作"Don't be too tired"或"Don't tire yourself out"。这两个表达都表示说话人希望对方不要因为过度劳累而感到疲倦。例句：

Don't be too tired. You need to take care of yourself.

Don't tire yourself out. You still have a long day ahead of you.

这两个表达的来源可能来自于日常的交流和对话中，在照顾对方的同时也希望对方不要太累。