What is the normal lung capacity of the human body

Many people have probably had to do a lung capacity test in their physical examinations from childhood to adulthood. Friends always like to compare their lung capacity with each other, but what is the normal lung capacity for the human body? I guess not many people can explain it in detail and analyze it. So, today we will popularize scientific knowledge and tell you about lung capacity.

Vital capacity (VC) refers to the total amount of gas exhaled after taking a deep breath.

Vital capacity = tidal volume + inspiratory reserve volume + expiratory reserve volume. Tidal volume refers to the amount of gas inhaled or exhaled with each breath. The supplementary inhalation volume is also called the inhalation reserve volume, which refers to the amount of gas that can be inhaled after a calm inhalation and then a strong inhalation. The supplementary expiratory volume is also called the expiratory reserve volume, which refers to the amount of gas that can be exhaled after a normal exhalation and then a maximum exhalation. Vital capacity is the maximum ventilation volume in one breath, which can reflect the potential capacity of respiratory function to a certain extent. The lung capacity of an adult male is about 3500 ml, and that of an adult female is about 2500 ml. The lung capacity of middle-aged people is the largest, while that of young and elderly people is smaller. The better the health of a person, the greater his lung capacity. Lung tissue damage such as tuberculosis, pulmonary fibrosis, atelectasis or lobectomy to a certain extent may reduce lung capacity. Kyphosis, pleural thickening, exudative pleurisy or pneumothorax may also limit lung expansion and reduce lung capacity. Therefore, a significant decrease in vital capacity is a manifestation of restrictive ventilation disorder. Since the measurement method of vital capacity is simple and has good repeatability, it is a commonly used indicator in health examinations. Because vital capacity measurement does not limit the exhalation speed, it cannot detect diseases of respiratory tract ventilation obstruction. Therefore, the timed spirometry method is more ideal as a dynamic indicator of lung function. Timed vital capacity is the maximum inhalation followed by the fastest exhalation until the exhalation is complete. At the same time, record the exhaled volume at the end of 1, 2, and 3 seconds respectively. A normal person should exhale 83%, 96% and 99% of his or her lung capacity respectively. People with obstructive pulmonary disease often need 5 to 6 seconds or more to exhale all their lung capacity; in many pathological conditions where respiratory movement is limited, the lung capacity in the first second increases, and the entire lung capacity can be exhaled ahead of time. Therefore, timed vital capacity can be used as a reference for identifying obstructive or restrictive ventilation disorders.

Lung capacity is closely related to human breathing. Physiological research shows that the organs, systems, tissues,

A low vital capacity test value (compared with the normal value) indicates that the body's ability to absorb oxygen and expel waste gas is poor. The oxygen supply inside the human body is insufficient, and some of the body's functions cannot function normally. Once the body needs to consume a large amount of oxygen (such as long-term study, work, and strenuous exercise), there will be a serious shortage of oxygen supply, leading to adverse reactions such as headache, dizziness, chest tightness, mental fatigue, inattention, memory loss, insomnia, etc. This will not only affect study and work, but also cause many irreparable losses to physical health.

Lung capacity varies by gender and age, with men having significantly higher lung capacity than women. Before the age of 20, lung capacity gradually increases with age, but after the age of 20, the increase is not obvious. The lung capacity of an adult male is about 3500 to 4000 ml, and that of an adult female is about 2500 to 3000 ml. Lung capacity mainly depends on the degree of expansion and contraction of the chest wall. Lung capacity decreases with age, falling by 9% to 27% every decade, but for people who exercise regularly, their lung capacity can still remain normal.

Physical exercise can significantly improve lung capacity. For example, you can regularly do some calisthenics exercises such as chest expansion and arm swinging, and persist in endurance running, swimming, playing football, playing basketball, shuttle running, etc. The lung capacity of middle- and long-distance runners and swimmers can reach more than 6000 ml.

Vital capacity to weight index:

The vital capacity-to-weight index is one of the composite indicators of anthropometric measurement and an important index of human respiratory function.

The vital capacity-to-weight index mainly reflects the correlation between vital capacity and body weight through the ratio of a person's vital capacity to body weight, that is, the relative value of vital capacity per 1 kg of body weight. It is used to conduct objective quantitative comparative analysis of individuals and groups of different ages and genders. It plays a certain reference role in the selection of athletes for oxygen metabolism events and the comprehensive evaluation of students' physical fitness. The calculation formula is: vital capacity/body weight. Unit of measurement: Vital capacity is measured in milliliters (ml) and body weight is measured in kilograms (kg).

How to measure vital capacity to body weight index:

The total amount of gas that is exhaled after the human body takes a deep breath with all its strength is part of the dynamic process of breathing. The quotient of the subject's actual vital capacity divided by his or her weight in kilograms measured on that day is the vital capacity index.

All the above content is what we introduced to you today about the normal human lung capacity. We hope it can help you. Lung capacity can generally reflect people's physical fitness and provide a reference value for everyone's physical health status. Therefore, everyone can use it as one of the standards to measure their own development. Exercising more can also increase your lung capacity.