Breathing tests, also referred to as pulmonary function tests (PFT) is a easy and vital diagnostic procedure. The respiratory capacity decreases by around 25%, after the age of 25 years, during which the respiratory function and efficiency of the lungs is at the ebb. Breathing capacity can be enhanced by yoga and other techniques, as aging results in poor breathing capacity and lung volume. Wheezing and gasping for breath are delayed indicators of lung damage. These tests can either measure the lung function or help in calculating the same. A single technique aiding in calculating and measuring all the lung values is not yet discovered. The lung function values is a good indicator of the lung condition and abstinence from harmful habits, such as smoking is advised.

Breathing Tests

The volume of air pushed out of the lungs is measured by spirometry. Any lung malfunction is detected by this test. The capacity of the lungs to add oxygen and eliminate carbon dioxide is checked. The speed at which the air is sent in and out of the lungs and the volume it can hold is assessed by spirometry. Early monitoring of lung malfunctioning can be done, thereby preventing further damage.

The rate of mortality of people suffering from obstructive lung diseases has raised.

An individual is allowed to blow in a hard manner into a tube, which is attached to the spirometer. A computer calculates and the results are drawn as graphs. The results indicate  the pace at which air flows out from the lungs, thereby detecting the presence of airway obstruction. The chart which projects the results in a printed format is referred to as a spirogram. The lung values, commonly evaluated are Forced vital capacity (FVC), Maximum voluntary ventilation (MVV), Expiratory reserve volume (ERV), Forced expiratory volume (FEV),  Forced expiratory flow, Slow vital capacity (SVC), Peak expiratory flow (PEF), Total lung capacity (TLC), Functional residual capacity (FRC) and Residual volume (RV).

Allergens, resulting in asthma or wheezing are detected using inhalation tests, which are termed as, provocation studies. Gases that pass through the alveoli or air sacs is measured. The result is given as values per minute in the gas diffusion tests which encompasses the gas diffusing capacity and gases in the arteries. Prior to an asthma attack, airway passage narrowing is revealed by a peak flow meter. This technique reveals the level of control of wheezing, due to medication. The appliance monitors the air curving out, and is termed, peak expiratory flow rate (PEFR).

Wheezing can also be detected by methacholine breathing tests. If the other methods fail to reveal the presence of Asthma, this technique is followed, wherein methacholine narrows the lung passage. Methacholine aerosol is inhaled prior to and after spirometry. The result portrays a directly proportional relationship, positive test meaning presence of asthma. Administration of a bronchodilator after concluding the tests is done to invert the effects of methacholine.