The bladder works like any machine, there is a certain optimal range under which it functions. For the bladder, volume is the biggest issue. The two times you will be most likely to have a poor urine flow rate will be when you have too little in your bladder (the bladder cant squeeze against this very small amount) and when you hold your urine so long that it is overstretched. The bladder is mainly composed of muscle. When the bladder is over-stretched, it loses its tone and hence, its ability to contract with its normal force. IC patients may have smaller bladder capacities than usual. We, therefore, often try to teach patients to slowly increase their bladder capacity over time, once their pain is under control. The process is called "bladder retraining." Patients are taught to progressively hold off going to the bathroom for longer and longer periods of time. In some instances, it can take well over a year to have optimal results. The point here is that it is a slow process. The patient who tries to increase the bladders capacity in several days is doomed to fail. Allowing the bladder to distend to a large volume very quickly often results in a poor urine stream. Patients then push and this then worsens any associated PFD - big headache.