What Is Anaerobic Metabolism?

Anaerobic metabolism is that the oxygen supply cannot meet the needs of the muscles during vigorous exercise. The muscles use anaerobic decomposition of adenosine triphosphate (ATP), creatine phosphate (CP) and anaerobic fermentation of sugar to generate lactic acid, release energy, and then synthesize adenosine triphosphate A metabolic process that muscles need.

Anaerobic metabolism

Anaerobic metabolism refers to the anaerobic participation in the breakdown of sugar in the muscles and the release of energy. Once a person is exercising, the thermal energy substance ATP (adenosine triphosphate) stored in the body can only be used for 15 seconds. After running for 100 meters, it will be used up. If you continue to run, the oxygen in the blood vessels will not keep up.

Characteristics of anaerobic metabolism of different athletes

Analyze the characteristics of anaerobic metabolism of different athletes and the relationship between anaerobic and aerobic capacity, and provide a reference for the evaluation of anaerobic metabolism. Methods The modified Wingate anaerobic test was used to determine the anaerobic capacity of Jiangsu provincial sprinters (n = 24), middle and long distance runners (n = 23), track bicycles (n = 11), and rowing boats (n = 18). Power, average work, fatigue), and determine its aerobic capacity by direct method. Results (1) Maximum power (PP / kg), average power (AP / kg), field bicycles belonging to short-distance projects [(15.1 ± 1.1) W / kg, (10.4 ± 0.7) W / kg] and sprinter [(14.9 ± 1.5) W / kg, (10.1 ± 0.8) w / kg] are higher than those belonging to long distance events

Aerobic and anaerobic exercise energy metabolism characteristics

What is aerobic exercise and what is anaerobic exercise? Most bodybuilders and bodybuilding enthusiasts only understand their expressions and are ignorant of them. They generally listen blindly during training. They are not very clear about the purpose of the training process, which affects the training consciousness and training effect. This article analyzes the characteristics of energy metabolism in aerobic and anaerobic exercise to help everyone to solve their doubts, understand the characteristics of bodybuilding and improve the consciousness of training. To understand the characteristics of energy metabolism in aerobic and anaerobic exercise, we must start with the role. Adenosine triphosphate (ATP) is the only direct source of energy for muscle activity, and it is also the direct source of energy for any other cellular activity in the human body (such as the secretion of glandular cells, the excitement of nerve cells, etc.). ATP is stored in cells, with muscle cells (muscle fibers) being the most. ATP consists of a macromolecule called adenosine and three simple phosphates. The last two phosphates have "high-energy bonds" and a large amount of chemical energy is stored on the bonds. Therefore, compounds such as ATP are also called high-energy phosphides. . When a phosphate bond at the end of ATP is broken, energy is released, allowing the cell to perform work or complete its physiological function.

During muscle activity, ATP stored in muscle fibers is rapidly decomposed into adenosine diphosphate (ADP) and inorganic phosphorus (PI) under the catalysis of ATP enzymes, releasing energy, dragging the filaments to slide, shortening the muscle fibers and completing work. However, the ATP reserves in the muscle are small, and must be synthesized while breaking down to continuously meet the needs of muscle activity and make the activity lasting. In fact, ATP is resynthesized as soon as it is broken down. The energy required for resynthesis depends on the specific conditions of the exercise. There are three sources: one is the liberation energy of creatine phosphate; the other is the glycogen digestion energy; the third is the oxidative energy of sugar and fat (and some proteins).

1. Decomposition of creatine phosphate. Phosphocreatine (CP for short) is another high-energy phosphide stored in muscle fibers that is closely related to ATP. It can release a large amount of energy when decomposed. When the muscle is contracted and very strong, with the rapid decomposition of ATP, CP also quickly divides the energy to enable ADP and PI to synthesize ATP. When the muscles are at rest, high-energy phosphides accumulate in the form of CP, so the content of CP in muscle cells is about 3-5 times that of ATP. However, its content is also limited. When CP is completely decomposed, it can only maintain vigorous exercise for a few seconds, and other energy must be supplied to regenerate ATP to maintain muscle activity. The significance of CP energy for ATP resynthesis is not in its content but in its rapid availability. Because CP can be quickly divided into two parts, it also does not require oxygen and does not produce lactic acid, so it is called the phosphogen system (ATP-CP system) in the energy supply system together with ATP. CP and ATP cannot be directly used as nutritional supplements. Because its molecules are too large to be absorbed by the body. Monohydroxycreatine can be directly absorbed by the human body, enter the muscle cells to synthesize CP, and then be used for the synthesis of ATP, which provides energy for muscle activity and has a certain good effect on strength training.

2. The fermentation of muscle glycogen. When the duration of exercise is more than 10 seconds and the intensity is great, the energy required by the body is far beyond what the phosphate system can supply, and the amount of oxygen supplied by the body is far from meeting the needs. At this time, the ATP resynthesis and energy required for exercise are mainly provided by glycogen fermentation. Glycolysis uses muscle glycogen as a raw material and generates ATP in the process of breaking down glucose into lactic acid. When the supply of oxygen is sufficient, part of the lactic acid is oxidized to generate energy in the mitochondria, and part of it is synthesized into liver and glycogen. Lactic acid is a strong acid. Too much accumulation in the body will destroy the acid-base balance of the internal environment, reduce muscle working ability, and cause temporary muscle fatigue. Therefore, relying on glycogen anaerobic fermentation for energy supply can only make muscles work for several tens of seconds. When anaerobic fermentation is used for energy supply, oxygen is not needed, but lactic acid is produced, so it is called a lactic energy system. The important significance of the lactic energy system is that it can still generate energy in the absence of oxygen for urgent needs in the body.

3. Aerobic oxidation of sugar and fat. When the supply of oxygen during exercise can meet the needs of oxygen, the ATP required for exercise is mainly powered by the aerobic oxidation of sugar and fat. Aerobic oxidation can provide a large amount of energy, which can maintain muscles' longer working time. For example, aerobic oxidation of glucose produced by glycogen produces 13 times more ATP than anaerobic glycolysis. This aerobic oxidation energy supply is called aerobic oxidation system.

Although both the phosphogen system and the lactic energy system supply a certain or even most of the energy during exercise, the final synthesis of ATP and CP and the elimination of lactic acid, the glycolytic product, are achieved by aerobic oxidation. So, the ultimate source of energy for muscle activity is the aerobic oxidation of sugar and fat (and perhaps protein), which in turn comes from food.

The degree and procedure of sugar and fat preferential use are different during exercise. This is mainly affected by two factors, one is exercise intensity and duration, and the other is diet. It is also related to the degree of training.

Influence of exercise intensity and duration. As exercise intensity increases and duration decreases, sugar is the dominant energy source. Because in a short time and high intensity exercise, the production of ATP is mainly provided by the lactic energy system, that is, ATP is produced by anaerobic glycolysis, and glycogen is the only energy source for anaerobic lysis. High-intensity, short-term exercise (such as weightlifting), the main source of ATP resynthesis is CP, and the anaerobic digestion of sugar can only provide a small amount of energy. Low-intensity, long-term exercise, fat has become the main energy source. In the later stages of long-term continuous exercise (such as marathon running), about 80% of ATP comes from fat oxidation. Although fat is the main energy source for prolonged vigorous exercise, sugar is still important, especially at the beginning of exercise. At the beginning of long-distance running, sugar is heavily used. As the exercise continues, sugar is slowly and steadily lower than the utilization of fat.

the impact of diet. The type of diet has an important effect on how much sugar or fat is used during exercise. In endurance sports (such as long-distance running), ordinary (mixed) dieters (about 55% of sugar, 30% of fat, and 15% of protein) start with sugar and then gradually switch to using fat. After eating a high-fat, low-sugar diet for a few days, the priority is to use fat during exercise, but the time of fatigue and exhaustion is much earlier. After eating a high-sugar, low-fat diet for a few days, the energy that is preferentially used during exercise is sugar. As the exercise continues, it gradually leans towards the use of fat. .

Training level. The exercise load is the same, and the proportion of those who use the fat for energy supply is higher than that without the training. Of the total energy required for exercise, 51% were provided by fat and 41% by non-trainers.

Anaerobic metabolism

Although protein can be used as an energy source in aerobic systems, it is usually not used. Only when sugar and fat are unavailable, a large amount of protein is used for energy, such as when prolonged severe starvation and excessive prolonged exercise.

In summary, although the absolute value of the energy supplied by the phosphogen system in the human body is not large and can be maintained for a short time, its main role lies in the rapid availability of energy. Short-distance sprinting, jumping, throwing, sprinting, weightlifting and other sports that need to be completed within several minutes, all rely on the system's storage as the main energy source. The energy of the lactic acid system comes from the anaerobic fermentation of muscle glycogen. The final product of the fermentation is lactic acid. The released energy is received by ADP and then synthesized into ATP. It is the main energy source of the body under hypoxia. Anaerobic training can improve the energy supply capacity of the human lactic acid energy system. When the same intense quantitative exercise is completed, the blood lactic acid of the trained person is lower than that of the untrained person. However, after completing a short period of strenuous exercise, the blood lactic acid of the trainees was 20-30% higher than that of the non-trainers. This is related to the higher glycogen content in the muscles of the trainers and the increase with the training Related to the level of glycogen use. The important role of the lactic acid system, like the phosphorogen system, is to supply energy quickly under temporary hypoxia. For example, in the bodybuilding training, a group of exercises is completed by the lactic acid system to provide energy.

The aerobic oxidation system refers to the decomposition of sugar or fat into carbon dioxide and water with the participation of oxygen, and at the same time generates a large amount of energy to make ADP resynthesize ATP. Aerobic oxidation system is the main energy supply system for long-term endurance activities. It can be seen that the energy provided by the energy supply system during human exercise is closely related to the sports project. The so-called "anaerobic exercise" refers to sports that mainly provide energy during anaerobic metabolism (phosphogen system and lactate energy system) during exercise, such as weightlifting and bodybuilding training. Aerobic exercise refers to sports that are mainly powered by the aerobic oxidation system during exercise, such as long-distance running to reduce body fat during bodybuilding training.