Dyspnea, or shortness of breath, that occurs during exertion has several possible causes. The sensation is not typically a cause for concern, but a person should seek medical help in certain cases.
Depending on the cause, dyspnea can occur alongside other symptoms, such as a tight chest and anxiety.
Read on to learn more about dyspnea on exertion, including the possible causes and when to see a doctor.
Dyspnea on exertion means that a person feels short of breath during exercise.
It can cause someone to feel as though they are running out of air and cannot breathe fast or deep enough while exercising or exerting physical effort.
Dyspnea on exertion can also cause:
- uncomfortable or difficult breathing
- chest tightness
- a sensation of suffocating or gasping or gulping for air
- anxiety and fear
While some people only experience dyspnea during intense exercise or exertion, others may develop it from simple activities, such as:
- going up steps
- sitting still
Dyspnea on exertion is a
However, if a person experiences dyspnea that comes on suddenly for no apparent reason or is very intense, they may require medical care.
According to a
- central nervous system (CNS)
- peripheral chemoreceptors
- mechanoreceptors in the chest wall and respiratory tract
The medulla, a structure in the brain stem at the top of the spinal cord, primarily
High CO2 levels make the blood more acidic. This lower pH causes the medulla to trigger hyperventilation, which is a rapid increase in breathing where the body exhales more air than it inhales. This action helps the body regain balance by reducing excess CO2.
On the other hand, when CO2 levels are too low, the medulla reduces respiration rates to help increase them. Three nerve groups in the medulla control different aspects of breathing.
Mechanoreceptors in a person’s airways, trachea, lungs, lung vessels, and chest wall detect how much these structures expand and contract with breathing. They communicate with the medulla, telling it how much space is available to fill with air.
The brain coordinates breathing rate and volume by sending signals to the respiratory muscles of the diaphragm and chest, as well as the muscles surrounding the lungs. It tells them how much and how quickly to expand and contract.
However, a wide range of respiratory, cardiac, and systemic conditions can also cause or trigger dyspnea on exertion. These
The following conditions may cause dyspnea on exertion.
Respiratory conditions are a common cause of dyspnea on exertion. Common respiratory causes include:
- aspirated (inhaled) objects
- acute exacerbation of chronic obstructive pulmonary disease (COPD)
- lung cancer or injury
- pulmonary embolism
- pulmonary edema
- pneumothorax, or a collapsed lung
- sarcoidosis or other abnormal growths
- hiatal hernia
Healthcare professionals will treat each case of dyspnea on exertion differently depending on its cause.
Common treatment options for respiratory causes include:
- inhalers, such as antimuscarinics, corticosteroids, and short- or long-acting bronchodilator inhalers
- supplemental oxygen therapy
- chemotherapy or radiation therapy
- surgery to remove cancerous lung sections, tumors, or abnormal growths
- surgery to repair a collapsed lung, a hiatal hernia, pleurisy, pneumothorax, or a pulmonary embolism
- rest and fluid therapy
- emergency procedures to remove inhaled objects
- thoracentesis, a procedure to remove excess fluid from the lungs
As the cardiovascular system plays a role in respiration, several cardiac conditions are associated with dyspnea on exertion. These include:
- acute coronary syndrome
- congestive heart failure
- cardiac arrhythmia
- pericardial tamponade
- intracardiac shunting
- valvular heart defect
- pulmonary hypertension
Common treatment options for cardiovascular causes of dyspnea on exertion include:
- angiotensin converting enzyme (ACE) inhibitors
- diuretic medications
- surgery to place shunts, correct defects, or repair damage
- implantable cardioverter defibrillator (ICD) or left ventricular assist device (LVAD)
Researchers have also linked several systemic conditions, which are those that affect the whole body, to dyspnea on exertion.
Common examples include:
- acute renal failure
- liver cirrhosis
- metabolic acidosis
Treatments that target systemic causes of dyspnea on exertion include:
- intravenous antibiotics
- medications and treatment to control vitamin, mineral, and fluid levels
- epinephrine auto-injectors, such as EpiPen
- medications to lower blood pressure
- radioactive iodine, beta-blockers, or carbimazole
- surgery to remove part of the thyroid
A doctor may also recommend making changes to everyday habits, such as:
- taking iron, vitamin B12, folic acid, and vitamin C supplements
- reaching or maintaining a moderate body weight
- avoiding or limiting alcohol intake
- managing diabetes or metabolic syndrome properly, for those with these conditions
- eating a healthful, balanced diet, including dietary sources of iron, such as dark leafy greens, beans and pulses, dried fruits, and fortified products
Chemical and environmental irritants
Chemical and environmental irritants can also cause dyspnea if a person has exposure to them or inhales them during exercise or exertion.
Examples of these irritants include:
- air pollution
- chemical fumes
- tobacco smoke
- mold spores
The treatment for dyspnea on exertion that occurs due to chemical or environmental irritants depends on the specific cause, but common options include:
- stopping smoking or avoiding exposure to tobacco smoke
- wearing protective covering and breathing devices when exposed to chemical fumes
- avoiding going outside or to places where pollution, dust, pollen, or smoke levels are high
- spending as little time outside as possible when mold spores are in the air at high levels, which is often in summer or fall in the United States
People should speak with a doctor if they experience frequent dyspnea that does not seem to be due to being unused to exercise, exercising too intensely, or exercising under challenging environmental conditions.
They should also talk with a doctor if dyspnea during exercise is severe or disabling or develops suddenly without a clear cause.
People who may be experiencing an asthma attack or an attack of another respiratory or cardiac condition, such as COPD, should seek emergency care.
A person should also seek emergency care if the following symptoms accompany dyspnea upon exertion:
- loss of consciousness or unexplained sleepiness
- chest pressure or chest pain
- high fever or chills
- irregular heartbeat
- severe or worsening cough with or without mucus
- bluish or discolored skin, starting at the lips and fingertips
- increased urinary frequency at night
- swelling in the abdomen, legs, ankles, or feet
- unexplained exhaustion
- coughing up blood
- swelling of the tongue, lips, mouth, or throat
- swelling with a rash
- bruising more easily than usual
- pale or yellowish skin
- cold hands and feet
- unexplained weakness
- chronic lack of appetite
- unexplained weight loss
- unexplained itchy skin
- reduced urination
- irregular menstruation
- severe sore throat and trouble swallowing
- abnormal, high pitched breathing sounds
Many people experience the sensation of breathlessness or restricted breathing while they are exercising. It is often harmless and goes away with rest.
However, for some people, dyspnea during exertion is a sign of an underlying respiratory, cardiac, or systemic condition, many of which require medical attention or emergency care.
It is important to consult a doctor when dyspnea during exertion is unexplained, sudden, severe, or disabling, or if one of the more serious symptoms listed above accompanies it.