Metabolism is a sum of occasions which are lugged out in the human being body to create energy and also other substances essential for its activities. In our organism there room catabolic and anabolic processes.

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Catabolism is a process during which organic matter is damaged down and also the power is simultaneously released. It is characterized by missing reserves of glycogen and also mobilisation the non-saccharide sources of energy – fats and also proteins. Catabolism bring away place throughout increased movement task and is crucial to sustain life functions.

Anabolism, on the various other hand, is a energy-consuming process during i m sorry substances are created. The substrate supply exceeds the instant need. The biology creates power reserves, tissues room created and also renewed. Anabolic procedures are widespread in cases of diminished physical activity.

The an easy nutrients (carbohydrates, lipids, proteins) are present in food us eat. Those are transformed and soaked up through the digestive system. Carbohydrates breakdown into individual carbohydrates (monosaccharides) wherein the glucose ranks among the most important ones. Lipids breakdown into complimentary fatty acids and glycerol. Proteins break down into amino acids. These straightforward agents deserve to then become involved in more complex processes.

Carbohydrates are supplied in both anaerobic and aerobic activities. ATP resynthesizes indigenous glycogen (muscle glycogen, liver glycogen) i beg your pardon transforms right into glucose. Supplies of glycogen in the human being body space restricted. Lipids are provided in endurance-based movement task of short intensity. While the use of proteins in the ATP resynthesis is an extremely limited, complimentary fatty mountain are supplied to a large extent. Glucose is created through gluconeogenesis.

Muscle metabolism

Muscles need energy to create contractions (Fig. 6). The energy is derived from adenosine triphosphate (ATP) existing in muscles. Muscles often tend to contain only minimal quantities the ATP. When depleted, ATP demands to it is in resynthesized from various other sources, specific creatine phosphate (CP) and also muscle glycogen. Various other supplies of glycogen are stored in the liver and also the human being body is also able to resynthesize ATP from lipids, i.e. Complimentary fatty acids. Different modes of energy coverage space used depending upon intensity and duration the the workload put on the organism.

Figure 6 power for muscles

The ATP-CP system

The above mentioned ATP and also CP are the energy sources of muscle contraction (Fig. 7, 8, 9). The manufacturing of power used in muscle contraction takes location through the anaerobic method (without oxygen).

Figure 7 ATP molecule


Figure 8 ATPase (ATP malfunction and power production for muscle contraction)


Figure 9 ATP resynthesis from CP

Anaerobic glycolysis

It is a chemical process during which ATP it s okay renewed from glycogen, i.e. Glucose in one anaerobic method (without access to oxygen). In these processes lactate, i.e. Salt the the lactic mountain is created in muscles. This energy system to produce 2 molecules of ATP. Glycolysis - change of glucose into 2 molecules of the pyruvate generating the network yield from ATP molecules and also 2 NADH molecule (anaerobic break down of glucose right into pyruvate and lactate) – see. Fig. 10.

Oxydative system

This is a chemical process during which the ATP resynthesis takes location through one aerobic method (with access to oxygen). Both glycogen or glucose and totally free fatty mountain act below as resources of energy.

Aerobic glycolysis takes ar in the cytoplasm the the cell whereby 34 ATP molecule are produced from the glycogen, i.e. Glucose with oxygen existing (Fig. 10).

Figure 10 Anaerobic and also aerobic glycolysis


Free fatty acids existing in mitochondria that muscle fibres transformed right into acetyl CoA are provided in the ATP resynthesis. Acetyl CoA start the Krebs cycle and thus ATP molecules are generated.

Individual power systems get associated according come the intensity of a movement task carried out. If the power is carried out at the preferably level, over there is a gradual involvement of all the solution (Fig. 11, 12).

Figure 11 power coverage under preferably workload


Figure 12 energy coverage under preferably workload


Types that muscle fibres

Human muscle fibres have unique qualities. Back nowadays almost 30 species of muscle fibres are known to be existing in the human body, we have tendency to job-related only v the following three types:

Slow red muscle fibre ns (SO - slow oxidative fibres)

The slow red muscle fibre is typified through a high aerobic capacity and resistance to fatigue. Together their anaerobic capacity is slow, they space not able to show good muscle strength. Muscle contraction tends to be slow – 110 ms/muscle contraction. One motoric unit contains around 10-180 muscle fibres.

Fast red muscle fibre IIa (FOG – fast oxidative glycolytic fibres)

The rapid red muscle fibre shares part of features with a sluggish fibre or a fibre the IIx type. This fibre is typified by medium aerobic capacity and resistance come fatigue. It likewise shows high anaerobic capacity and is able come display good muscle strength. The rate of contraction is 50 ms/muscle contraction. One motoric unit contains about 300-800 fibres.

Fast white fibre IIx (FG – fast glycolytic fibre)

Unlike the formerly mentioned types the fast white fibre is characterized by short aerobic volume and propensity to quick fatigue. On the other hand, it has actually the biggest anaerobic capacity and also is able come display significant muscle strength. The rate of convulsion is 50 ms/muscle contraction. One motor unit contains about 300-800 fibres.

The volume that this kind muscle fibres is genetically given (up come 90 %) (Jančík et al., 2007) and varies in individual persons. In the average population the proportion of slow to fast fibres is 1:1. The following number (Fig. 13) mirrors the proportion of slow-moving to fast fibres in athletes involved in various disciplines.

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Figure 13 ratio of rapid (type FG and FOG) to sluggish (type SO) fibres in different kind athletes


In muscle convulsion individual species of muscle fibres acquire activated in accordance through the intensity of muscle movement. Throughout low strongness exercise sluggish fibres are generally recruited. However, with increasing intensity of exercise quick fibres get activated. That is necessary to note here that the fibre ratio differs in different muscles of the person body. For example, postural muscles often tend to contain much more slow fibres.