Everybody breathes and everybody pees, but most people don’t appreciate how the two bodily functions can be related to each other. Our internal body structures are systems under pressure that are influenced by the mechanical forces that we expose them to, both internally and externally. Structurally our bodies are divided into two separate regions: the thorax and the abdomen. The thorax is essentially from your shoulders down to the bottom of your ribcage, while your abdomen is the area encapsulated from your ribcage down to the bottom of your pelvis. Your thorax is a container constructed by your thoracic spine and ribcage to create a protective casing for your heart and lungs. Your abdomen is a softer structure stuffed with a lot of organs that all have their own role in keeping you alive.

The inside of your thorax is a relative negative pressure to allow for your lungs to expand and contract as you to breath. Conversely, the contents of your abdomen are under a positive pressure that is markedly influenced by muscular contraction of the abdominals, pelvic floor muscles, breathing and posture. The two compartments are separated by a thin domed muscle called the diaphragm that moves up and down to facilitate the process of breathing and directly influences the pressure in each cavity. Your bladder sits as a vulnerable little bag in the bottom of your pelvis and is directly influenced by the pressure of all the abdominal organs resting on top of it. How much pressure your bladder is exposed to is dependent on your postural strategies, i.e., how effective you are at physically stacking your thorax on top of your abdomen when you are in the vertical position.

Your organs are partially held in place by ligaments and fascia connecting them to the inside walls of your thoracic and abdominal cavities and partially by the pressures generated by your postural muscle recruitment. Unfortunately, our postural strategies can be less than ideal, and some people effectively end up feeling like a tube of tooth paste that someone is squeezing in the middle. Too much pressure held in the lower part of the ribcage will create a downward pressure of the abdominal organs onto the bladder and an upward force of breathing into the chest and shoulders. The result can be pressure based urinary incontinence during exercise and relatively inefficient breathing patterns that can contribute to tension and pain in the neck and shoulders.

I wrote an article on my blog and recorded a short video in 2010 titled Everything Your Mother Taught You About Posture is Wrong, trying to explain why “chest up, shoulders back and down” is not always the best postural advice for people. It has the tendency to have people carry themselves with their torso tipped backwards, shoulders overly braced and a relatively poor perception of how to use their abdominals while they are in the vertical position. Ideally, we learn to use our ribcage to support our shoulders, more than our shoulders to support our ribcage, and figure out how to lightly recruit our abdominal muscles to hold our trunk in a vertical position stacked on top of our lumbar spine. You will see three common postural strategies in the pictures below and you might infer how these habitual holding patterns affect the internal pressures of a person’s thorax and abdomen.

Posture affecting Pressures picture from Why We Hurt

Breathing is one of the only physiologic processes in the body that will happen completely subconsciously, but that you can also choose to step in, pay attention and take control of. How you breathe is strongly connected to your emotional state and what you perceive to be ‘good breathing’ is likely related to the training and life experience you may have had related to sport, posture and/or mindfulness. As a physiotherapist, I don’t believe that there is one magical way to breathe, but I think it is important that people understand and experience that there are multiple ways that you can do it and that each way can be useful in different circumstances. Understanding how to pay attention to your breathing and your postures can help relieve anxiety, decrease pain and tension in your body, and prevent many cases of urinary incontinence.

The muscles in your mid back work together with the muscles on the front of your thighs, while your abdominal muscles work together with your butt and hamstrings to effectively connect your upper body and your lower body in a functional way. Commonly people will end up developing postural strategies that are all one pairing or the other and have a hard time trying to recruit their gut and butt, or their back and quads during functional tasks. The result is typically some form of muscular bracing strategy that will impact the person’s efficiency of movement and the pressures inside their body. A big part of improving a person’s breathing, movement, and troubles with pressure incontinence, is creating awareness around their bracing strategies and teaching them some different ways to hold themselves.