How Does COPD Affect the Diaphragm?

The diaphragm is a large, dome-shaped muscle located directly below the lungs. You use it to breathe.

When you take a breath, the diaphragm contracts and flattens, which causes your chest cavity to expand. This creates a vacuum, which pulls air through your nose, down your windpipe, and into your lungs. When you exhale, meanwhile, your diaphragm relaxes and returns to its previous shape. This forces air back out of your lungs.

Healthy adults take between 12 to 28 breaths a minute or as many as 40,000 breaths in a day. Your diaphragm does much of the work involved in breathing, but your intercostal muscles—a group of 22 pairs of very small muscles located between your ribs—also play an important role by helping to expand and shrink the chest cavity with every breath.

Your Diaphragm and COPD

In people with chronic obstructive pulmonary disease (COPD), the diaphragm is weakened and doesn't work as well as it should during the breathing process. This seems to be due to changes in the cells of the diaphragm muscle that cause the muscle fibers to lose some of the force needed to contract and relax. These changes start to occur when you're first developing COPD.

When your diaphragm isn't working as well as it should, your body uses other muscles in your neck, back, and shoulders to do the work of contracting and expanding your chest. However, these muscles don't compensate fully for your weakened diaphragm, so you have trouble breathing.

Research shows that a very weak diaphragm muscle can worsen your COPD, potentially leading to exacerbations. People with COPD—even severe COPD—who have weaker diaphragms don't do as well as people who have stronger diaphragms.

Improving Your Diaphragm Strength

It's possible to exercise your respiratory muscles, which can help you breathe more easily.

The COPD Foundation recommends two breathing techniques to people with COPD: pursed-lips breathing and diaphragmatic (abdominal/belly) breathing. Both can help you feel less short of breath, but diaphragmic breathing can also help to strengthen your respiratory muscles and enable them to take on more of the very necessary work of breathing.

The diaphragmic breathing technique is a bit tricky to learn. Therefore, you should get some instruction from a respiratory therapist or physical therapist who understands the technique and can teach it to you.