Spiroergometry: Find a Specialist and Get Information

Spiroergometry is used to measure respiratory gases, specifically oxygen uptake and carbon dioxide output. The results provide insights into the functions

• of the heart,
• the lungs, and
• muscle metabolism

at rest and during continuously increasing exertion. The test also measures respiratory volume—that is, the amount of air transported per breath or per unit of time. 

The body continuously requires oxygen, which is transported from the lungs to the muscles via the blood, where it contributes to energy production. With the help of oxygen, nutrients and energy sources—primarily carbohydrates and fats—are broken down into their end products. Carbon dioxide is produced as a waste product, which is transported by the blood back to the lungs and exhaled.

When the body is under only moderate stress, energy production is aerobic. This means that there is sufficient oxygen available to completely break down the nutrients.

During more intense physical exertion, oxygen becomes scarce, leading to anaerobic (oxygen-free) energy production. Under these conditions, fats can no longer be processed, so only sugar is broken down. However, even sugar cannot be completely broken down without oxygen.

Consequently, an important and measurable metabolic byproduct is produced: lactic acid (lactate). The accumulation of lactate leads to acidosis in the body, and the body’s physical capacity is reached.

Spiroergometry is primarily used

• in sports medicine,
• in cardiology (heart and circulatory diseases), and 
• in pulmonology (lung medicine)

. Patients with lung diseases and heart failure often undergo spiroergometry. But

• people with unexplained shortness of breath during physical exertion or
• patients scheduled for high-risk surgery (such as a heart transplant)

are also evaluated using spiroergometry.

Sports medicine is the most common field of application for spiroergometry. Regular spiroergometry tests can document athletes’ performance and training progress. Using spiroergometry, physicians can

• measure endurance performance,
• energy expenditure, and
• individual performance limits 

. This so-called performance diagnostics provides relevant data that can be used to create a personalized training plan for athletes.

In cardiology, it provides insights into the condition of the cardiovascular system. In cases of lung disease, it assesses the function of lung tissue and the airways. Here, spiroergometry helps plan further therapeutic measures.

Typical conditions for which spiroergometry is ordered include, for example:

• Heart failure
• Coronary artery disease (narrowing of the coronary arteries)
• Exercise-induced asthma
• Respiratory and lung diseases (e.g., pneumonia, tuberculosis)

Other indications (areas of application) for spiroergometry include, for example

• preventive examinations,
• monitoring the effectiveness of medications, as well as
• fitness tests in occupational and space medicine.

Among the most important values determined during endurance performance testing are

• maximal oxygen uptake: This is the classic criterion for assessing physical performance
• the respiratory quotient: It is calculated by dividing carbon dioxide output by oxygen uptake.

Another measured value is the so-called anaerobic threshold, also known as the lactate threshold. This is the point at which the body begins anaerobic energy production, leading to an accumulation of lactate. A blood sample taken from the earlobe is typically used to determine the anaerobic threshold.

A spiroergometry test is performed by an internist or a specialist in heart and lung diseases. Athletes can have the test done by a sports medicine physician.

During spiroergometry, the subject must perform physical work on a special bicycle (ergometer) or treadmill. For competitive athletes, other devices, such as a rowing ergometer, may also be used. The exercise intensity is continuously increased using computer-controlled programs, with the rate of increase based on the patient’s individual exercise capacity

During spiroergometry, the test subject wears an airtight breathing mask connected to a measuring device. Gas samples can be collected through this mask. A modern method is the so-called breath-by-breath analysis, in which the gas concentration of each individual breath can be determined.

In addition, the patient is connected to an ECG and a blood pressure monitor during spiroergometry. This allows for continuous monitoring of heart rate and blood pressure.

In total, a spiroergometry test takes only about 10 minutes. This is usually followed by a five- to ten-minute post-test observation period. At the end of the test, the doctor evaluates the recordings, which are typically displayed graphically on a computer screen.

Health insurance covers the costs if the spiroergometry is performed due to suspected heart or lung disease.

However, athletes who wish to use spiroergometry for training planning must cover the costs themselves. A test costs about 170 to 180 euros.

The risks associated with spiroergometry are generally minimal. Since the test subject is continuously monitored by the doctor, there is only an extremely low risk of complications. During physical exertion, an increased respiratory and heart rate, as well as mild shortness of breath if present, are completely normal.

However, if more severe symptoms occur, the doctor must stop the spiroergometry test. If the test subject suffers from

• cardiac arrhythmias,
• severe shortness of breath,
•  dizziness, or
• chest pain,

the exercise is stopped immediately.

In some people, spiroergometry cannot be performed because the physical exertion would be too intense. This includes, for example, patients who

• a recent heart attack,
• pneumonia,
• severe heart failure, or
• acute thrombosis (blood clot).