Discuss the relationship between distribution of muscle fiber type and performance.
In a study from the US National Library of Medicine National Institutes of Health (1991), the relationship between muscle fiber and performance they tested two different groups of athletic boys between the ages of 11-13. The subjects were divided into two groups according their fiber distribution. The fast group comprised 10 subjects with more than 50% fast-twitch fibers and the slow group comprised 8 subjects with more than 50% slow-twitch fibers in their lateralis muscle (Mero, 1990). The 'fast' group had 59.2 +/- 6.3% and the 'slow' group had 39.4 +/- 9.8% type II fibers. Other clear differences (P less than 0.05-0.01) between the groups were observed as
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The heart is one of the strongest muscles in the body. According to Henry Gray's “Anatomy of the Human Body” (2015), the heart is roughly the size of a large fist and weighs between about 10 to 12 ounces (280 to 340 grams) in men and 8 to 10 ounces (230 to 280 grams) in women (Lewis, 2015). The human heart has four chambers: two upper chambers (the atria) and two lower ones (the ventricles). The heart's outer wall consists of three layers; epicardium (outermost wall), myocardium (middle wall), endocardium (inner layer). The tricuspid valve and the mitral valve make up the atrioventricular (AV) valves, which connect the atria and the ventricles (Lewis, 2015). The function of the heart is divided into two pathways: the pulmonary circuit and the systemic circuit. In the pulmonary circuit, deoxygenated blood travels to the lungs by way of the pulmonary artery, then returns as oxygenated blood to the left atrium of the heart via the pulmonary vein. The systemic circuit, delivers oxygenated blood to the body from the left ventricle to the aorta, and from there enters the arteries and capillaries where it supplies the body's tissues with oxygen. Then, deoxygenated blood returns through the veins to the venae cavae, re-entering the heart's right atrium to restart the
Both the right and left atrium contract causing blood to flow though the two valves, and then into the left ventricle. The left ventricle pumps blood into the systemic circulation through the aorta. This systemic circulation system is much bigger than the pulmonary circulation system, which is why the left ventricle is so big. The blood on the left side of the heart is oxygenated. It becomes oxygenated when the deoxygenated blood passes through the right atrium and then flows into the left ventricle. It is then pumped along the pulmonary artery into the lungs where it is oxygenated. It then travels through the pulmonary veins back into the heart. It enters through the left atrium and then travels to the left ventricle. This process is repeated over and over again, to make blood continuously flow through the heart, lungs and body. This process ensures that there is always enough oxygen for the body to work
The cardiovascular system, however, would not be able to effectively complete these functions without help from what is sometimes referred to as the body’s hardest-working organ- the heart. Approximately the size of a fist, the heart is contains four chambers (the uppermost are called the atria and the lowermost are called the ventricles) and four valves. Additionally, the heart is surrounded by the pericardium, a structure that serves to protect the heart, keep the heart stabilized in the chest, and
Abstract: In this experiment the measurements of skeletal muscle fibers of the rabbit are in millimeters. The average length for the three muscle fibers after adding the solution A which contained only 0.25% ATP in distilled water was 20 mm. The average length for the three muscle fibers after adding the solution C which contained 0.5M KCl and 0.001M MgCl2 in distilled water was 1.77 mm and the average length for the three muscle fibers after adding the solution B which contained 0.25 % ATP and 0.5 M KCl with 0.001 M Mgcl2 in water was 1.77 mm.
In a normal human being the heart correctly functions by the blood first entering through the right atrium from the superior and inferior vena cava. This blood flow continues through the right atrioventricular valve into the right ventricle. The right ventricle contracts forcing the pulmonary valve to open leading blood flow through the pulmonary valve and into the pulmonary trunk. Blood is then distributed from the right and left pulmonary arteries to the lungs, where carbon dioxide is unloaded and oxygen is loaded into the blood. The blood is returned from the lungs to the left
The heart is basically a pump that has to circulate the blood around the body delivering oxygenated blood to our organs and then returning deoxygenated blood to our lungs. There are four chambers in the heart, two atria and two ventricles. There are four main valves, mitral, aortic, tricuspid and pulmonary7b.
Rationale, Significance and Hypothesis. An extrinsic factor, which exerts a dominant influence on skeletal muscle fiber phenotype, is the nervous system. Buller et al. (1960) elegantly demonstrated the plastic nature of skeletal muscle fibers in response to changes in innervation type. Later, Lφmo and Westgaard (Lφmo and Westgaard, 1974; Westgaard and Lφmo, 1988) demonstrated that depolarization of muscle with specific patterns and frequencies of electrical activity are sufficient to cause changes in mature muscle fiber phenotypes. However, how myofibrillar gene expression and structural organization is affected by the frequency of impulses during activity, the amount of activity over time, or other characteristics of patterned activity is essentially unknown. To answer these questions will require the isolation and study of subsets of muscle-specific proteins in relation to different electrical activation patterns in vivo, an issue that cannot be easily addressed in preparations currently used in the study of muscle development and maintenance. However, using novel in vivo approaches can, in part, circumvent this difficulty.
Each type of muscle fiber has a different power output. These fibers are fast-twitch, and slow-twitch muscle fibers. Fast-twitch fibers are used for explosive movements that are sustained for a short amount of time. While slow-twitch fibers are used for periods of time when movement is sustained for a long period. Slow-twitch fibers utilize aerobic beta-oxidation for energy. This means this type of muscle fiber uses fatty acids for energy and requires oxygen to break them down. This breakdown takes place within the mitochondria. Fast-twitch fibers get energy from anaerobic glycolysis. Meaning this fiber utilizes the breakdown of glucose without oxygen. Humans are born with these fibers in different proportions than others. Genetics determines the amount of each fiber a person will have, and these pre-genetically determined number of fibers will remain constant throughout a person’s life. Due to the different capabilities of each fiber, the amount of slow and fast-twitch fibers can determine the person’s capability. Therefore, those who have more fast-twitch fibers will jump higher than those with more slow-twitch fibers of the same stature. (BSC 228,
Oxygen and nutrients the body requires for function are pumped around this complex network of blood vessels by the heart. At roughly the size of a human fist, the heart is a four-chambered muscle and performs two functions of circulation simultaneously and continuously. Systemic and pulmonary circulation. The heart is made up from three separate layers of cardiac tissue; the outer layer called the pericardium, which is a double sac-like outer covering with serous fluid inside to keep the middle layer, the myocardium from adhering to the outer layer. This middle layer of the heart is the heart muscle which is thicker on the left side, to aid with the pressure needed to sustain systemic circulation. The inner layer of the heart is the endocardium. It’s lining is smooth to help prevent the blood which circulates around the inside of the heart from clotting. The heart is the human body’s in-built pacemaker, and the electrical signals sent through the it cause the heart to contract and relax. This process is triggered by the autonomic nervous system and the contraction and relaxing cycle is
The heart consists into three layers in which are endocardium, the myocardium, and the epicardium. The endocardium is the inner layer of the heart (chambers and valves). The myocardium is the middle muscular layer which is responsible for heart contraction. The epicardium is the outside layer of the heart
The heart is a very strong muscle that has one major job. The heart’s job is to pump blood throughout the entire body. The heart is made up of 4 chambers, and 4 valves. There is the right and left atrium, and a right and left ventricle. The atriums are the superior chambers, and the ventricles are inferior chambers. The left ventricle is the most important, because that is where the blood travels through to go to the aorta, and eventually the rest of the body (Taylor 2015).
Individual muscles are made up of individual muscle fibers and these fibers can be further organized into a motor unit grouped within each muscle. A motor unit is simply a bundle of grouped muscle fibers. When you want to move the brain instantaneously sends a signal or impulse through the spinal cord that reaches the motor unit. Muscle fibers are cells like the basic building block of the muscle. There are a few different types of muscle fibers, each are designed for a specific type of muscle activity. Some muscle fibers are good for endurance exercises, other work best for the short bursts. Each muscle fiber is a single cell. Each cell consists of a structure.
Almost 80% of people die from heart disease. The only way to know your level of risk is to be assessed by a healthcare professional and to be checked for factors such as your blood pressure, cholesterol and glucose levels, waist measurement and BMI. Once you know your overall risk, agree with your healthcare professional on a plan for specific actions you should take to reduce your risk for heart disease and stroke. The Circulatory System is made up of three main parts: The heart, the blood vessels and the blood. Sometimes the watery fluid called lymph and the vessels that carry it are considered to be part of the Circulatory System. The heart is a special pump that pumps the blood around the body. The purpose of this paper was to summarize information about the heart, explain how it works, and discuss its purpose. It was said that the heart evolves through several different stages inside the womb, first resembling a fish's heart, then a frog's, which has two chambers, than a snake's, with three, before finally adopting the four-chambered structure of the human heart. I also told you how the heart works. When the heart contracts, the chambers become smaller, forcing blood first out of the atria into the ventricles, then from each ventricle into a large blood vessel connected to the top of the heart. Now the purpose of the heart is the size of its owner's clenched fist, the organ sits in the middle of the chest, behind 1the breastbone and between the lungs, in a moistened chamber that is protected all round by the rib cage. It can also be easy to fix the heart. The only way to know your level of risk is to be assessed by a healthcare professional and to be checked for factors such as your blood pressure, cholesterol and glucose levels, waist measurement and BMI. The heart is very important for your
The heart is located beneath the rib cage, between the lungs, to the left of the sternum (breastbone). Most people believe that the heart is located on the left side of the chest because the bottom of the heart is tipped to the left. Therefore, you feel more of your heart on the left side. The heart is a powerhouse with muscular walls that contract, thrusting blood throughout the body’s blood vessels. The blood must flow in one direction in order for the heart to function properly. The three focal types of vessels are arteries, capillaries, and veins which form the circulatory system. These vessels, like elastic tubes, transport blood to every portion of the body. Arteries carry oxygen-rich blood away from the heart to all of the body’s tissues. They progressively become smaller as blood is carried further away from the heart. The capillaries are the small, thin blood vessels that connect the arteries to the veins. Nutrients, carbon dioxide and waste products are allowed to pass to and from the tissue cells by their thin walls. Veins, on the other hand, carry the oxygen-poor blood back to the heart. These vessels gradually become larger as they get near to the heart. The blood vessel system runs over 60,000 miles long.
has to work harder pumping blood to the rest of the body. Blood in our
From my high school Human Anatomy and Physiology class, I vaguely remember the structure of the human heart. The human heart is fairly simple at a non-cellular level. Your heart contains a right and left atrium, and directly under those, a left and right ventricle. These are the four chambers of the human heart. Your heart also has two main exiting arteries: the pulmonary trunk which exits from the right ventricle and the aorta which exists from the left ventricle. The pulmonary trunk carries “dirty”, deoxygenated blood from the right ventricle to the two lungs to become oxygenated in a system called the pulmonary circuit. This oxygenated blood is then carried back to the left atrium by the pulmonary veins. The aorta carries this freshly oxygenated blood to the entire body in a system called the systemic circuit. The inferior vena cava and superior vena cava are major arteries leading into the heart, carrying the “dirty” blood to be cleaned. (See figure one). I know of these parts, however I want to know how these parts are able to function together as the body ages.