be running on empty idiom  informal         
 勉强支撑(虽精疲力竭仍打起精神继续工作并保持活跃)
to continue to work and be active when you have no energy left
  I get the impression he's been running on empty for months now. A holiday will do him good. 我感觉他如今有好几个月都是在勉强支撑。放个假对他会有好处。 
  mainly US and Australian English空转(某人或组织没有新思想,或不如以前有效率) 
If a person or an organization is running on empty, they have no new ideas or are not as effective as they were before.
  The fund-raising campaign was running on empty after ten years under the same leader. 十年都在同一个人的领导下,资金筹集活动只是在空转。