muscle fatigue

MUSCLE FATIGUE
HOW DO MUSCLES GET THE ENERGY TO WORK?
In muscles, it is essential that Calcium is present, as this gives the muscles the ability to contract and relax. For muscles to contract energy is needed: the energy can only be provided by the breakdown of a chemical called adenosine triphosphate (ATP). As ATP is broken down, a phosphate molecule is broken off, reducing the phosphate molecules, from 3 to 2. This produces adenosine triphosphate. However for the muscles contraction to continue, the ATP has to rebuild from ADP and p (ADP+P+= ATP). As this occurs, more energy is released and so more energy is available. Therefore, when the muscles is used for an extended time the ATP supplies are lowered. This is the most important anaerobic fuel source accessible.The equation for ATP(energy) is ATP-> energy+ adenosine diphosphate(ADP+P). there are two pathways anerboic and aerobic respiration. aerobic requires oxygen in order for respiration to take place. The equation for this is glucose + oxygen -> carbon dioxide + water(+energy). Anerboic respiration does not require oxygen it only happens when there is not enough oxygen for aerobic respiration. The equation for this is glucose -> lactic acid (+energy relesed).
When a muscle contracts it creates movement which is called an isotonic contraction. An isotonic contraction can normally concentric where the muscle shortens as the fibres contract. Muscle fibres use ATP for contraction but only for a few seconds, as when the fibres contract the muscle lengthens leaving the muscle to contract with no follow-on movement.
The fastest way to regenerate ATP (energy) is by the breaking down of creatine phosphate to provide creatine and an additional phosphate energy to convert ADP back to ATP. This benefits contracting muscles because ATP is therefore available very quickly. This can only happen for a short period of time the creatine phosphate stored in the muscle is used quickly, especially during high intensity workouts. Although many athletes take creatine supplements it adapts this into creatine phosphate in the muscles. Taking supplements exploits the levels of creatine phosphate stored in the muscles, therefore the amount of energy stored is maximised.
Another method where ATP can be produced in the muscle cell can be through glucose and glycogen. This can occur during physical activities, The body needs an energy source. The energy source is a molecule called glucose. The cells of the body breaks down glucose through a process called glycolysis. Glycolysis energy is transferred from bonds in the glucose molecule to phosphate bonds in ATP and GTP. What normally happens is glucose is broken down in to glycolysis to form ATP, NADH + H+ and 2 molecules of pyruvate. Glucose is converted to pyruvate after their conversion to one of the sugar intermediates in this glycolytic pathway.
The last method where ATP can be produced is in the muscle cell from fatty acids this can be broken down into various tissues which produce energy. This gives a high yield of ATP throughout fatty acid oxidation & oxidative phosphorylation.
They are preferentially used by some tissues as a most important energy source.
Heart muscle derives 60% of its energy from long-chain fatty acid oxidation
And skeletal muscle uses them at mutually rest but during extended aerobic muscle exercise.

WHAT IS MUSCLE FATIGUE AND WHAT CAUSES IT:
Muscle fatigue is when people work out and feels a sensation that their muscles are tired, aching or exhausted it gets to the point that they are working out so hard that they feel as they cannot move the muscles anymore. When this happens, the muscle that is artificial will not be able to function as it did at the beginning of a workout. Although the muscles do develop microscopic tears that must be repaired in order for the muscle to grow in strength and size. Muscle fatigue does stop the muscles from contracting normally as a result of lactic acid from anaerobic respiration.On the other hand lactic acid builds up in the muscle as it is a waste product that is supplied to the muscle as a result of minimum oxygen.

However there are many causes of muscle fatigue as many Universities have found that calcium channels that leak during exercise can be the cause of muscle fatigue. This can take place because when calcium releases in a muscle; it makes the muscle protein contract and fatigues the muscle. Another cause is that exercise is the most common as it usually indicates that your workout was able to challenge your muscles adequately to require rest. Although another cause of fatigued or weakened muscles is an injury. Soft injuries do not element sharp, recognizable pains. Often an injury shows as tedious pain in a generalized area, parallel to exercise-induced muscle fatigue.
On the other hand because of muscle fatigue you lose the ability to continue the workout two things that might have an influence on this are vigorous workouts or lacking the right nutrients like protein therefore not having the normal force to do a workout. Also by the body undergoing anaerobic respiration the muscles don’t get enough oxygen therefore resulting in build-up off lactic acid in the muscles also affecting them not to contract normally hence causing muscle fatigue.
Anaerobic metabolism is where athletes use oxygen more rapidly than supplied therefore glycogen being broken down to diffuse lactic acid into the blood stream causing it to go the muscles as a result causing pain cramps or sometimes nausea. The equation for this is C6h12o6+6o2 gives you co2+6h2o and energy.
Therefore when you work out for a long period of time this is what mainly causes muscle fatigue as during a workout the body does not keep up with the demand of oxygen from the muscle. This is known as oxygen debt were the cells does not contain enough oxygen so they start to respire so without the oxygen this creates lactic acid which causes muscle fatigue.

`The processes that allow muscles to recover after exercise:
The problems caused by lactic acid are mainly muscle fatigue as it is very common nevertheless Pyruvate is the end creation of glycolysis/glucose breakdown (which occurs in the cell cytosol). If oxygen is continuing pyruvate is decarboxylase to Acetyl CoA and reaches at the Krebs cycle (also called TCA cycle), where some ATP is directly shaped and the electron carriers NADH and FADH2 are generated for oxidative phosphorylation, the final step of aerobic respiration which produces high quantity of ATP for cellular purposes.The muscle will get to the point where the contraction will stop this is because the red blood cells are not carrying enough oxygen for the muscle to continue.

If oxygen isn't current in sufficient quantities (anaerobic respiration), pyruvate is condensed to lactate/lactic acid, this generates minor amounts of ATP in itself for short term use in muscle cells. Post-exercise, the lactate is either oxidized back to pyruvate, or is transported to the liver where it enters a passageway called gluconeogenesis, which produces glucose.

Glycogen --> Glucose --> Pyruvate -- (anaerobic) -->Lactate

For the body to get rid of lactic acid is during power exercises such as sprinting, when the rate of demand for energy is high, lactate is produced faster than the ability of the tissues to remove it and lactate concentration begins to rise. however when lots of lactic acid is produced, the removal is slow since the transport proteins are overwhelmed and lactic acid cannot get out as fast as it is made.The equation for this process is ATP+CADP+CP=ATP+C

Oygen debt can only be caused when theres to much lactic acid and not enough oxygen. when oxygen debt happens anerobic respiration takes place to gain back the oxygen.

The effects on athletes of spending time at high altitudes:

There are many effects on athletes of spending at high altitude like throughout anaerobic respiration, there is a lack of oxygen pyruvic acid with an absence of oxygen forms lactic acid . However because the air is thinner and lighter there is a lack of oxygen . This affect the athletes because there is a reaction in the kidney. The respiration that takes place is anerobic because this occurs when not enough oxygen is availabe.High altitude could recover athletes capacity to exercise moreover exposing the body to high altitude which causes it to change the lower level of oxygen accessible in the atmosphere. Maximum of the changes that happen with acclimatization improve the delivery of oxygen to the muscles the theory being that more oxygen will lead to improved performance.

Therefore for any type of exercise lasting longer than a few minutes, the body must use oxygen to produce energy without this muscle can become damaged. Also the body produces s a hormone called erythropoietin which stimulates the production of red blood cells which carry oxygen to the muscles where it shows the more blood cells you have the more oxygen is delivered to your muscles. There are many of changes that can happen throughout acclimatization which can help athletic performance. When there are a quantity of small blood vessels as it changes in the microscopic structure and function of the muscles themselves.