The Diaphragm

The Diaphragm

I have previously talked about how addressing the cause of a problem, rather than just treating the symptoms with soft tissue work is important in really making a difference. This doesn’t always happen, however, and one of the most overlooked areas is the diaphragm. For the last week I have suffered increased bloating due to my IBS and for the first time ever was also experiencing shortness of breath just from a few minutes of walking. My whole abdomen right up to the rib cage felt tight and it dawned on me that since the breathing problems were most likely due to the diaphragm being pulled tight, maybe the diaphragm could be involved in other issues that I commonly treat clients with, for example:-

LOWER LIMB - Reduced internal hip rotation with passive hip and knee flexion in the supine client – can be helped with rib cage depression upon exhalation on the same side as the limited movement. The client will also feel less of a pinch in the groin. Therefore working on the diaphragm and pelvis is indicated rather than the glutes.

UPPER LIMB – reduced internal rotation of the shoulder – can be helped with passive upper rib cage depression alongside retraction and internal rotation of the shoulder, while the client inhales and exhales. It may be that the issue is due to the diaphragm and rib cage rather than a shoulder pathology.

Therefore objective joint assessment is essential rather than fitting the client’s symptoms into a ready made treatment.


DIAPHRAGM – skeletal muscle which separates the chest from the abdomen. It attaches to the ribcage, and therefore is involved in movement of the ribcage.

PELVIC FLOOR (DIAPHRAGM) – a hammock which incorporates the levator ani and coccygeus muscles, separating the abdomen from the pelvis

 These muscles are involved in pelvic movement.    ie. when the diaphragm lengthens into its natural dome shape, upon exhalation:-

  • The transverse abdominis and rectus abdominis contract allowing the ribcage to depress under the diaphragmatic dome
  • The obliques contract, retracting the ribcage

As sports therapists we sometimes assess a client’s hamstrings by asking them to perform the toe touch test, but this test could also be an indication of diaphragmatic tension, because the ribcage has to depress and retract, ie. the obliques have to contract which means that the diaphragm has to be lengthened.If the diaphragm is tight it won’t do this as effectively and the client may have difficulty performing the test.  If the ribcage remains elevated and protracted, this encourages anterior pelvic tilt which may then impact on the hamstrings, due to a change in the resting muscle length.

So if, for example, a client is struggling to bend over to put their shoes and socks on,it may not be a case of looking at the spine or the glutes and hamstrings, but the diaphragm. This activity calls for hip flexion and posterior pelvic tilt, mobilising the pelvic floor to its end range, and depression and retraction of the rib cage which involves mobilisation of the diaphragm to its end range. If the diaphragm and pelvic floor are unable to mobilise in this way, then the muscle length/tension balance will be affected, making other movements inefficient.

Therefore, to promote maximum efficiency of the abdominal muscles and glutes, the diaphragm must be free to perform to the end range of motion during respiration.


There are numerous factors contributing to tension in the diaphragms and the pelvic floor is covered extensively in a couple of my courses, but common factors affecting both diaphragms include:-

  • Trauma
  • Chronic stress
  • Altered breathing patterns and respiratory drive, commonly due to respiratory conditions or sympathetic dominance of the nervous system (fight or flight response - hyperventilation means short and fast breaths out so the diaphragm remains contracted for longer) Once breathing pattern is altered the accessory respiratory muscles eg. scalenes, serratus etc kick in to maintain adequate respiration, causing further compensatory problems
  • Abdominal bloating eg. due to bowel disorders


When chronic stress, pain and hyperarousal increase wear and tear on the body and reduce its ability to maintain homeostasis, certain systems within the body, including the respiratory system, adapt to meet the demands of the body. In clients with PTSD, even anticipating perceived threats will impact on the respiratory system, reducing exhalation and therefore increasing the time that the diaphragm is contracted.

Therefore conditions such as PTSD, depression, grief etc can also affect metabolic functions because the respiratory and nervous systems respond to emotions rather than chemoreceptors, thus potentially altering homeostasis more long term. By working on the diaphragm and desensitizing the respiratory system, a normal breathing pattern and nervous system functioning can be restored, enabling better sleep, better metabolic functioning and increased ability to manage pain. 


  • Respiratory conditions eg.COPD, cystic fibrosis, asthma that affect breathing can cause abdominal bloating
  • Women’s health issues eg. menstruation, ovarian cancer
  • Pregnancy – bloating, nausea, shortness of breath may occur when the foetus pushes against the diaphragm
  • stress related disorders eg.hyperventilation, anxiety, panic attacks
  • digestive issues eg. obesity, lactose intolerance, coeliac disease, irritable bowel syndrome, gastroparesis, constipation
  • Cancer related eg. ascites, Non-Hodgkins lymphoma
  • gallstones
  • hernia
  • pancreatic insufficiency
  • peripheral neuropathy
  • overeating and excessive air swallowing - can increase pressure on the diaphragm, encouraging shortness of breathcertain foods eg. lentils, beans, cabbage, carbonated drinks – may contribute to excess gas and increase pressure on the diaphragm


Irritable bowel syndrome (IBS) affects 11% of people, and part of the difficulty in assessing and treating it, is the apparent lack of structural abnormalities. Research has shown, however, that electrical diaphragmatic activation in IBS patients is often dysfunctional, and this could potentially could be a contributing factor in lower back pain that accompanies IBS. Also if the ability of the diaphragm to contract is restricted, this can have a negative impact on gut motility.

Visible abdominal bloating and tightness are common in IBS, and this can lead to shortness of breath due to restricted movement and increased pressure on the diaphragm. This shortness of breath can then cause quick and short breaths which further restrict diaphragmatic movement or swallowing air which increases the bloating.