How to Create an Optimal ZOA:
90/90 Bridge with Ball and Balloon Exercise

One technique that has been developed by the famous Postural Restoration Institute™ is the 90/90 Bridge with Ball and Balloon. This technique is designed to help restore the positioning of the ribs and spine to a proper position in order to allow the diaphragm optimal ability to perform both its respiratory and postural roles.

  • Lay on your back with your feet on the wall, bringing the hips and knees to a 90 degree angle.
    • This places your lumbar spine in a slightly flexed position, tilts the hips towards your back, and internally rotates the ribs. We stack the ribs “on top” of the hips to stimulate a proper ZOA.
  • Place a medium sized ball (larger than a baseball, smaller than a basketball) between the knees.
  • Create tension through the core (squeeze your abs).
  • Hold a balloon in one hand, place the tongue on the roof of the mouth to allow for adequate space of the airway, and inhale through the nose for about 3-4 seconds.
  • Exhale through the mouth for about 6-8 seconds, filling the balloon with air.
  • Pause for 2-3 seconds and repeat.
  • Be sure not to pinch off the end of the balloon with the teeth or fingertips.

The slow breathing pattern this creates helps relax the autonomic nervous system (the body’s natural stress reaction, mentioned previously) by bringing down the heart rate, decreasing muscle tone and supporting recovery.
A healthy thoracic volume is the key to the relationship of core with upper and lower limbs. The muscles of the core create stability of your spine, which will then allow for mobility and optimal rotation of the shoulders and hips. Next time your hips feel tight and can’t seem to rotate, or when your shoulder lacks the mobility to go over your head, check your core and see if you can better align your Zone of Apposition!


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​Anatomy of the Diaphragm​

The diaphragm muscle completely separates the thoracic cavity (heart and lungs) from the abdominal cavity. 

Origin, Insertion and Function

The diaphragm is attached to the sternum and the xiphoid process, the lower 6 ribs, and the top 2 to 3 lumbar vertebra. The upper surface of the dome acts as a floor for the organs of the thoracic cavity, while the lower surface acts as a roof and wraps over the organs in the abdominal cavity.

As you inhale 70% of lung expansion results from rib cage expansion and 30% from descent of the diaphragm. Since 30% of the total lung expansion depends on the full function of the diaphragm - full descent during inspiration, and full ascent during expiration - it is of utmost importance to ensure proper breathing patterns.

The diaphragm plays a role in the stabilization of the lumbar spine especially during sudden voluntary movement of the limbs, therefore the diaphragm has the ability to support breathing and provide increased postural stability (9). However, with increased demands of breathing the role of diaphragm in postural stability decreases.​

Zone of Apposition

The Zone of Apposition (ZOA) is the zone of healthy diaphragm movement your chest and ribs should have the capacity to move through. Your ZOA is affected by the ability of the thorax (ribs) and spine to move together (10). How does spinal and ribcage positioning lead to sub-optimal ZOA? Lack of rotation and flexion at the spine and inefficiency of the thoracic cage to rotate.

As you can see, the optimal ZOA depicts a dome shaped diaphragm, neutral cervical, thoracic and lumbar spine, and optimal ribcage position whereas sub-optimal ZOA depicts the diaphragm more linear, exaggeration of the curve on each spinal segment, and ribcage elevation and external rotation.

​Better Breathing – Why You Should Breathe Deeper Today

Did you know? You inhale and exhale about 26,000 times every day! That comes down to over a thousand times per hour, or almost twenty times each minute. Because you breathe so often (and need to do it to live!) you tend not to think about the way you breathe – even if your respiration patterns are less than optimal.

Maintaining optimal respiration patterns, stability, and posture is always important, and is even more challenging during exercise. A common trend in those with less-than-optimal breathing patterns is the tendency to compensate in the shoulders and hips – which makes sense because these joints surround the abdomen, where the mechanics of breathing occur. This compensation can then negatively affect many of our movement patterns – both in activities of daily living and exercise.

The squat is one example of an exercise movement pattern that highlights these negative effects. The hip and ankles, which should be more mobile, cannot efficiently move due to stiffness. This decreases stability in the knees. The same thing occurs in the lower back, which should also be stable – when the hips lose the ability to rotate, the lower back will jump in to meet the demands of the movement. This in turn will lead to overuse injuries.

Low back pain is one of the most common complaints by adults to medical professionals, and one of the main reasons even among professional athletes for missing training sessions and playing time (4). It is also correlated with faulty posture, such as an excessive curvature of the lower back (lumbar lordosis)  (5,6). Lumbar lordosis causes shortening and tightening of the paraspinal muscles and hip flexors, and lengthening and tightening the abdominal muscles, glutes, and hamstrings.​

Specific stabilization exercises have been shown to decrease low back pain. The abdominal drawing in maneuver (ADIM) is a well-known maneuver which helps to increase low back and pelvis stabilization through co-contracting transversus abdominis and multifidi (abdominal and spinal stabilizers). You can find instructions to perform the ADIM at:

Although this is a great exercise, it can be only half of the solution for individuals with suboptimal breathing.Stress and anxiety may also cause muscular tension and shallow respiration through autonomic arousal – the body’s natural reaction to stress. The muscles used for good posture and breathing may be inhibited, causing other muscles to overwork. This results in inefficient breathing patterns leading to muscular, myofascial, and joint paint especially during physical activity

and exercise.