What is Shortness of Breath?
Shortness of breath is a subjective, complex, and difficult-to-measure breathing discomfort. This experience can be unpleasant or stressful, and its intensity varies (Parshall AJRCCM 2012; Demoule ERJ 2024).
During physical exertion, a certain degree of shortness of breath is normal. The key question is whether the perceived shortness of breath is normal or abnormal and disproportionate. At rest, shortness of breath can occur in both healthy individuals and those with a lung condition. In healthy individuals, this sensation is often caused by a dysfunctional breathing pattern or hyperventilation.
It is important to remember that the sensation of shortness of breath has a significant impact on stress, anxiety, and emotional well-being. This effect is observed both at rest and during exercise and competitions. During intense training sessions or competitions, shortness of breath makes exertion feel more difficult (RPE). By improving breathing techniques, shortness of breath can be reduced, leading to lower stress levels and improved sports performance.
Conversely, individuals experiencing high stress, feeling unwell, or athletes facing excessive stress before or during a competition often report increased shortness of breath (von Leupoldt et al. 2010). By addressing stress, shortness of breath can be reduced, positively impacting quality of life, training, and sports performance. We address stress and well-being through education. Helping individuals to understand why they experience certain symptoms already reduces a significant portion of stress. We then introduce physical exercises combined with mental training to further alleviate stress and shortness of breath.
Shortness of Breath During Exercise
When we exercise, our breathing adapts to the body's metabolic demands. In other words, our breathing ensures that enough oxygen is supplied to working muscles while also expelling sufficient CO2. The harder our muscles work, the more CO2 they produce. The lungs regulate CO2 levels to prevent acid buildup in the body. As physical exertion increases, CO2 production rises, requiring the lungs to ventilate more to expel the excess CO2. This increased lung activity results in a stronger sensation of shortness of breath.
To determine whether the experienced shortness of breath is normal or abnormal, various breathing tests are available.
Shortness of breath is influenced by exercise intensity but is also closely linked to the inspiratory neural drive (Jolley ERJ 2015). Jolley suggests that patients experiencing shortness of breath can improve their exercise capacity by working on their breathing patterns (Jolley 2015).
Jolley’s study demonstrates that the sensation of shortness of breath correlates more strongly with inspiratory neural drive than with the total volume of air ventilated (liters per minute). Additionally, Jolley found that the relationship between shortness of breath and ventilation diminishes when the lungs can no longer expand or contract efficiently (Jolley ERJ 2015).
Another study by Migliaccio highlights the complex but significant impact of breathing frequency on sports performance. Breathing frequency is regulated independently of tidal volume (Nicolo et al. 2017) but follows breathing depth. In other words, deeper breaths result in a lower breathing frequency, while shallower breaths lead to an increased breathing rate. This finding is crucial because breathing frequency, via the central nervous system, determines how strenuous an activity feels.
Every athlete knows that exertion feels heavier when muscles produce more lactic acid (lactate). However, breathing frequency is even more closely linked to the perception of effort (RPE) than lactate concentration in the muscles (Nicolo et al. 2017).
Breathing frequency determines:
- The perceived difficulty of exercise
- The sensation of shortness of breath
- Oxygen transport to the muscles
- CO2 expulsion from the body
- Focus and concentration
- The autonomic nervous system: heart rate, blood distribution to muscles, energy levels
Training breathing patterns at rest and during exercise helps to lower the breathing frequency, allowing athletes to perform better because a lower breathing frequency:
- Reduces the perception of effort
- Decreases the sensation of shortness of breath
- Enhances oxygen transport to muscles
- Optimizes CO2 balance
- Improves focus and concentration
- Supports autonomic nervous system function: lower heart rate, better muscle circulation, more energy
(Nicolo 2017)
Air Hunger, Shortness of Breath, and Hyperventilation
Air hunger is the sensation that makes people feel the need to take deep breaths regularly. This can occur at rest or can be triggered by exercise. It often leads to deeper breathing than necessary, resulting in chronic hyperventilation. Air hunger and hyperventilation significantly impact breathing mechanics and overall physiology.
People experiencing air hunger often respond by sighing deeply, yawning, coughing, or clearing their throat frequently. If you feel the need to take deep breaths or yawn regularly, it is due to air hunger. This sensation causes excessive breathing relative to metabolic needs, leading to physical discomfort that is difficult for doctors to objectively assess or diagnose, often being labeled as "medically unexplained symptoms."
Air hunger significantly affects the perception of shortness of breath, both at rest and during exertion, by reducing inspiratory reserve capacity a key factor in shortness of breath. It can negatively impact daily life and sports performance by causing physical symptoms, increasing breathlessness, and affecting the autonomic nervous system. Fortunately, this condition can be effectively managed through tailored breathing exercises, breath-hold training at rest and during exercise, end-expiratory breath-hold sprint interval training, relaxation, and meditation.
Shortness of Breath and the Nocebo Effect
Expectations play a significant role in shortness of breath. If someone expects to feel more shortness of breath, they are more likely to experience it. Conversely, if someone expects less shortness of breath, they are likely to feel less of it. This is the nocebo and placebo effect on breathlessness (Vinckier et al. 2021). Overcoming negative expectations and rebuilding confidence in the respiratory system is a key component of our approach. We achieve this through specialized breathing exercises and mental training.
What Is the Placebo Effect?
A placebo is a product, idea, or belief that has no active effect. The positive outcome occurs solely due to an individual’s expectations or conditioned past experiences (Szabo, A.). The placebo and nocebo effects demonstrate the power of the human mind in shaping future outcomes. While this mental effect often works against us (nocebo), it can also be trained to work in our favor (Szabo, A).
What Is the Nocebo Effect?
The nocebo effect is the opposite of the placebo effect. In this case, a non-effective product, idea, or belief causes a negative outcome due to an expectation of harm or negative past experiences.
Placebo in Medicine
When pharmaceutical companies test new drugs, they must demonstrate their effectiveness against a placebo. It is well known that a significant portion of individuals respond to placebo treatments, with some being more susceptible than others.
Placebo in Sports
Scientific research has demonstrated a strong placebo effect in sports. Positive expectations or beliefs improve performance, particularly in areas like nutrition and supplements (Chhabra 2024). Weightlifters showed performance improvements of up to 23.8% with a caffeine placebo (Duncan 2009), while cyclists improved by 8% when they believed they were inhaling oxygen-enriched air. Similar placebo effects have been observed with equipment and recovery products. Additionally, simply believing that one is in peak physical condition is a powerful performance-enhancer!
Nocebo in Sports
Believing that something is wrong with one’s breathing or body can significantly hinder athletic performance. Studies show that the nocebo effect in athletes is nearly twice as strong as the placebo effect (Chhabra 2024). For example, an athlete’s belief that they consumed harmful substances resulted in performance declines of 22% to 49% (McLemore et al. 2020).
Tests for evaluating shortness of breath at rest and during exercise:
At rest:
- Observation
- Lung function tests
- Questionnaires (e.g., Nijmegen Questionnaire for hyperventilation)
- Breath-hold test
During exercise:
- CPET (Cardiopulmonary Exercise Test)
- Breathing frequency assessment
- Repeated sprint interval protocol
(Nicola A Hanania et all. 2019)