By Maria Baylon, RRT, RCP

As a clinician who’s been practicing in pulmonary rehabilitation for 22 years, at times I’ve found myself questioning whether we truly teach our patients how to breathe efficiently. More specifically, why do some patients swear by pursed-lip breathing (PLB), diaphragmatic or belly breathing, cyclic sighing, and other methods while others find these techniques less helpful?

The Pursed-Lip Puzzle

Let’s use pursed-lip breathing as an example.

For patients with COPD, this technique has long been taught to help manage shortness of breath. Research¹ suggests that exhaling through gently pursed lips creates a small amount of positive pressure within the airways, helping to keep them open longer during exhalation. (At the UC San Diego Pulmonary Rehabilitation program, we use the chant “Smell your coffee, cool down your coffee.”) This may reduce air trapping and dynamic hyperinflation, allowing patients to empty their lungs more effectively before taking the next breath. By performing this breathing exercise, the hope is that our patients will naturally slow their respiratory rate, improve their breathing efficiency, and experience less breathlessness during activity. Giving our patients practical tools to navigate one of the most distressing symptoms they experience and feel enabled to keep moving is our goal and may be one of the greatest successes of pulmonary rehabilitation, in my opinion. But can we truly maximize these tools within the six- to eight-week sessions that participants attend pulmonary rehab?

It Depends on Your Perception

According to conversations I’d had over the years with participants on graduation day, the answer is often a resounding “yes.” As part of the discharge process, our team always asks whether patients have continued using pursed-lip breathing during daily activities and whether they feel it has helped them function better at home. Most of my participants with COPD report that PLB has made a significant difference in a relatively short period of time. They describe being able to recover more quickly after climbing stairs, ambling through the grocery store, or completing household chores and activities that once felt overwhelming.

What is more interesting, however, is how perception plays out in the six-minute walk test (6MWT). At the end of the evaluation, I often notice what appears to be “moderate” breathlessness, yet when I ask patients to rate their perceived breathlessness, many describe it as only "very slight." The disconnect between what I observe and what the patient experiences has made me ponder the true value of breathing retraining. Maybe PLB’s greatest impact is not always something we can measure by simply watching a patient's breathing pattern. Perhaps instead, it is helping patients feel more in control of their breathing, lessening the fear associated with breathlessness and giving them the confidence to continue moving despite their fear. On the other hand, there are patients who say PLB has not really improved their breathing with everyday activities even though, per an observing clinician, their breathing technique shows improvement at discharge compared to their initial session. These moments remind me that a patient's perception of breathlessness is just as important as our clinical observations as rehab professionals.

The CALM Way

Breathing effectively is closely connected to confidence, control, and our perception of effort. Curiosity led me to read emerging research, including the work of Anna Norweg and colleagues on Capnography-Assisted Learned Monitored (CALM) Breathing.² For those with COPD, dyspnea can lead to breathing patterns that become increasingly rapid, shallow, and inefficient. These patterns may contribute to lower end-tidal carbon dioxide (ETCO₂), heightened anxiety, and an ongoing cycle in which breathlessness and fear can feed off each other. CALM Breathing, as a potential bridge intervention before pulmonary rehabilitation, may help interrupt this cycle by enabling patients to recognize their breathing patterns, understand what they are seeing through real-time capnography biofeedback, and gradually develop more efficient breathing behaviors before beginning exercise training. By increasing awareness and self-regulation of breathing, patients may enter pulmonary rehabilitation with greater confidence and with a stronger foundation for applying the breathing techniques taught throughout the program.

As I read about CALM Breathing, I couldn't help but reflect on my own experience training for a half marathon. While my shortness of breath as a runner is very different from the chronic dyspnea experienced by my patients, I noticed how closely my breathing was tied to my mindset. If I started a run too fast or became anxious knowing that I had only been running for two miles, my breathing became rapid and shallow, making the run feel much harder than it really was. When I slowed down, focused on my breathing, and settled into a comfortable rhythm, I felt more in control and the run became more manageable and enjoyable. That experience helped me better appreciate the concept behind CALM Breathing. It isn't simply about changing the way someone breathes, it is about helping them recognize when their breathing becomes dysregulated and giving them tools to regain control.

Where Do We Go From Here?

Pulmonary rehab has always been about adapting and collaborating and can be defined by resilience, adaptability, and innovation. Emerging approaches such as Capnography-Assisted Learned Monitored (CALM) Breathing allow us to think beyond teaching PLB as an isolated skill and helps patients better understand their own breathing patterns through education, awareness, and biofeedback. Whether through traditional pursed-lip breathing, emerging interventions and adjunct therapies like CALM Breathing, or future innovations we have yet to venture into, our greatest success may not only be teaching patients how to breathe, but also empowering them to trust their breathing once again.

Maria Baylon, RRT, RCP, is the lead case coordinator at UC San Diego Health Pulmonary Rehabilitation.

REFERENCES

¹ Araujo CLP, Karloh M, Reis CM, Mayer AF. (2015)  Pursed-lips breathing reduces dynamic hyperinflation induced by activities of daily living in patients with COPD: A randomized crossover study. J Rehab Med. 2015;47:957-962.

² Norweg, Anna et al (2023). Capnography-Assisted Learned, Monitored (CALM) breathing therapy for dysfunctional breathing in COPD: A bridge to pulmonary rehabilitation" Journal of Contemporary Clinical Trials. https://www.sciencedirect.com/science/article/pii/S155171442300263X