It usually takes me a day to recover from my short fasts. The symptoms that made my fast difficult leave shortly after I break, but after breaking the fast I feel a different kind of weakness and have a need for rest. Therefore, I try to break at night or at least give myself time to rest before having to go to work. Of course, I also have to make sure I am near the bathroom which is another good reason to break it giving myself plenty of time before going to work or social occasions. Other then that I am fine. A longer fast would take several days of recovery time.