Understanding how a healthy bladder should work
Before looking at the types of things that can go wrong with your bladder and pelvic floor it’s helpful to understand how a healthy bladder works.
Where is my bladder and what is it made of?
The bladder is a balloon like structure made from layers of muscle. The innermost lining of the bladder that’s in contact with urine is made of connective tissue.
If you find your belly button and feel in a straight line downwards you will come to a rim of bone. This is the pubic section of your pelvis and your bladder sits just behind the pubic bone (shown in white on the diagram)
The diagram shows a bladder that is filling with urine as it drains from the kidneys.The uterus and vagina lie just behind the bladder.The back passage sits behind the vagina.We have three tubes and three holes that lie very close to each other.
A day in the life of your bladder: a time to fill and stay relaxed
One of the main roles of the bladder is to fill up, act as reservoir and store urine. When you wake up to start the day your bladder is usually full to around it’s maximum capacity.
Let’s look at the cycle of events after you’ve emptied your bladder at the start of the day.
For most of the day your bladder is filling up with the urine that constantly passes in small amounts through 2 tubes (ureters) down from your kidneys.
That means that unless you have just emptied your bladder there will always be some urine present.
Your bladder should stay calm and relaxed and be able to hold around 400ml to 600ml.
It’s normal to be able to last 3 to 4 hours between trips to the toilet to pass urine.
A day in the life of your bladder: a time to tighten and empty
Once your bladder is full its role switches from being relaxed and storing urine to the action where it tightens emptying out its contents; because the bladder is a muscle, it has the ability to contract and squeeze urine out.
So, as the bladder slowly fills, it stretches and sends messages through the nervous system to the brain. When the bladder has reached its maximum capacity these messages become stronger and you experience that strong urge to pass urine.
You should be able to easily control this urge until you reach the toilet.
Once sitting comfortably a reflex action causes the bladder muscle to tighten, we consciously relax our pelvic floor muscles and urine then flows freely away as the bladder empties.
Women often hover over a toilet. If you do not sit down your pelvic floor muscles do not fully relax. If these muscles are tense your bladder may then not be able to fully empty.
A day in the life of your bladder: a time to repeat the process
This process of filling and emptying continues throughout the day and night. Your bladder should never dominate your thoughts and dictate your daily activities. The whole process should occur in the background of your life.
Emptying your bladder ‘just in case’ effects the process of allowing it to fill to its maximum capacity and then empty.
People often say they have a ‘weak’ bladder as they experience ‘urgency’ and have to rush to the toilet when they need to pass urine. Although there are different medical conditions that can cause these symptoms the most common condition is an overactive bladder or OAB.
OAB symptoms can be a real nuisance but people often put up with problems for years without seeking advice.
Simple bladder re-training and lifestyle changes often help to improve symptoms. Medication can also be useful.
Electrical stimulation units can be programmed to calm an overactive bladder. If your pelvic floor muscles are very weak they may not be able to contract well enough to calm down your overactive bladder reflexes.
Electrical stimulation can also be helpful in improving the action of very weak pelvic floor muscles.
Other blogs in this section of the site will look at bladder training, lifestyle changes as well as use of electrical stimulation as a treatment for overactive bladder symptoms.
de Smit Medical has been working alongside Chartered Physiotherapist, Jane Appleyard to create a blog for advice and thoughts on a range of topics relating to the pelvic floor. Return to our blog for more articles and videos.
Jane Appleyard has over 30 years' experience as a Chartered Physiotherapist and specialises in pelvic health. You can read Jane's bio here.