Muscle research

1.Muscle needs energy to move and as stated previously the ‘universal energy currency’ of living systems is ATP (adenosine triphosphate).  This is largely produced within mitochondria, organelles which are often referred to as the ‘powerhouse’ of the cell. The ATP that results is used to provide the power for the muscle fibres to contract. Contraction itself (i.e. actual shortening movement) occurs when a bond is broken between ATP and one of its three phosphate bonds.  It is the energy that is liberated by the breaking of this bond that causes the movement. Hence ATP is broken down to ADP (adenosine diphosphate). ADP is reconverted to ATP by donation of a phosphate from another high energy phosphate store in the muscle, creatine phosphate . Mitochondria can burn glucose, fats and ketones to make carbon dioxide and water. Doing so ensures that a greater percentage of aerobic metabolism can be sustained, i.e. a subsequent slightly greater availability of oxygen and production of ATP. A diet rich in creatine has the potential to increase the availability of creatine phosphate, which can increase high energy phosphate supply during intense exercise. Mitochondria can burn glucose, fats and ketones to make carbon dioxide and water. They will do so give an adequate supply of oxygen.http://www.runsweet.com/Muscles.html

2.Muscle fatigue, or physical fatigue, is the decline in ability of a muscle to generate force. It can be a result of vigorous exercise but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction. There are two main causes of muscle fatigue. The limitations of a nerve’s ability to generate a sustained signal neural fatigue and the reduced ability of the muscle fiber to contract metabolic fatigue. Muscle fatigue, or physical fatigue, is the decline in ability of a muscle to generate force. It can be a result of vigorous exercise but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction. There are two main causes of muscle fatigue. The limitations of a nerve’s ability to generate a sustained signal (neural fatigue) and the reduced ability of the muscle fiber to contract (metabolic fatigue). http://en.wikipedia.org/wiki/Muscle_fatigue

3.The metabolic and muscle blood flow response in recovery from exercise is dependent on the type and the duration of the exercise. Immediately after both intense static and dynamical exercise blood flow to the exercised muscles increases suggesting that blood flow is mechanically hindered by muscle contraction. After the initial rise (seconds) muscle blood flow decreases at a moderate rate and the time to reach resting flow levels varies from seconds to more than 30 min. It is unclear as to what causes the elevated blood flow during recovery. A mismatch between the time course of changes in blood flow and oxygen uptake suggests that the blood flow is not directly regulated by the need of oxygen in the exercised muscles. The hyperaemic response may be linked to locally released factors, such as ions and metabolites. However, the signal by which the blood flow is elevated remains unknown. After exercise both pulmonary and muscle oxygen uptake decrease rapidly, but can remain above resting levels for several hours. Resynthesis of substrates such as CP, ATP and glycogen cannot account for the entire excessive post-exercise oxygen uptake (EPOC)

in the exercised muscles and the cause of the elevated muscle oxygen uptake in recovery from exercise remains to be assessed.http://www.ncbi.nlm.nih.gov/pubmed/9578376

4.Athletes from many sports have used altitude training to prepare for a big match or event, and not just when the event will be at a high altitude. They do this because the air is "thinner" at high altitudes meaning there are fewer oxygen molecules per volume of air. Every breath taken at a high altitude delivers less of what working muscles require.While the effect is most dramatic at altitudes greater than 8,000 feet (2,438 meters) above sea level, it is noticeable even at 5,000 feet (1,524 meters) above sea level.To compensate for the decrease in oxygen, one of the body's hormones, erythropoietin (EPO), triggers the production of more red blood cells to aid in oxygen delivery to the muscles.You might have heard of EPO in news stories about performance-enhancing drugs. A synthetic version of EPO has been used by endurance athletes to mimic the body's natural process of red blood cell creation. So far, most sports organizations are more concerned with this artificial version rather than triggering it naturally up in the mountains. athletes train at higher altitudes reek the benefits then take it to competition in lower altitudes http://www.livescience.com/32750-why-do-athletes-train-at-high-altitudes.html