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This is rarely seen due to the restrictions of eight specific tenketsu known as the Eight Gates , which limit the amount of chakra an individual can release at a single given time. Day and night, the muscles of your heart contract and relax to pump blood throughout your body. It's not unusual for a first blood pressure reading to be high if a child is nervous, so the health care provider will likely take three readings, then use an average of the three to determine whether a child has or is at risk for high blood pressure. Exercise , the training of the body to improve its function and enhance its fitness. Overcoming setbacks Walking for fitness: Golgi tendon organ GTO , a structure of the nervous system found throughout the body at the intersection of muscle fibers and tendons.
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In addition, not only will you improve your overall cardiovascular endurance, but the efficiency of your entire cardiovascular system as well. The cardiovascular system is defined as your heart and the circulatory system. The cardiovascular system is responsible for transporting food, metabolic wastes, hormones, and gases to and from the individual cells within the body. Included within the circulatory system are the heart, lunges, blood vessels, and blood.
As previously stated, when performing an aerobic exercise the intent is to increase your heart rate to your target heart rate and thereafter, maintain that level for a minimum of 20 consecutive minutes. There are several health, fitness, and mental well-being benefits associated with regularly achieving an aerobic effect and are as follows:. Strengthens the muscles involved in respiration through facilitating the flow of air into and out of the lungs.
Strengthens the heart, allowing it to more efficiently pump and circulate blood throughout the entire body. Promotes efficient transport of oxygen throughout the entire body through an increase in the total number of red blood cells within the body.
Increased the total number of calories burned by the body and hence, assists in weight loss and weight management. Increases high density lipoprotein HDL levels, the good cholesterol, while reducing low density lipoprotein LDL levels, the bad cholesterol. Improves muscular strength depending on the exercise type , flexibility, balance, coordination, and joint range of motion.
In addition to the health, fitness, and mental well-being benefits associated with regularly performing an aerobic activity, performance improvements are also realized.
Below is a brief list of several of the performance benefits associated with aerobic exercise:. Improves endurance by increasing the storage of energy molecules i. Allows for a greater level of energy to be released by increasing the rate in which aerobic metabolism is activated within the muscles. Improves the ability of muscles to utilize fats as an energy source during exercise while maintaining intramuscular glycogen levels.
In order to obtain the benefits listed above most sports physicians recommend that, as a minimum, an individual perform an aerobic activity that will achieve their target heart rate for a minimum of 20 consecutive minutes, 3 times per week.
In addition, it will be necessary to modify your aerobic activity to ensure that you are continually achieving an aerobic effect and that you are forcing your body to constantly improve its cardiovascular condition.
In general, aerobic exercises are performed over a longer period of time and at a moderate level of intensity. Running or jogging at a moderate pace over a fairly long distance is considered an aerobic activity.
Playing singles tennis where you are continually moving is typically considered an aerobic activity. On the other hand, playing team tennis or performing any other activity where short bursts of energy are followed by inactivity are considered anaerobic activities. For individuals that jog or run, you may want to consider modifying the course that you run i.
In another example, swimmers can continually improve their cardiovascular conditioning by modifying their swimming routine to include more difficult swimming strokes or decrease the time in which it takes to complete a specific distance.
There are two basic forms of exercise: The primary differences between the two are defined by the duration and intensity of the muscular contractions and how the energy within the muscles are generated. During the initial stages of an aerobic exercise, glycogen is broken down to produce glucose. Thereafter, the glucose reacts with oxygen to produce carbon dioxide and water. The result of this process is a release of energy. Once these carbohydrates have been depleted, the metabolism of fat will begin.
The metabolism of fat is a slow process and is typically accompanied with a decrease in performance. As the body transitions to consuming fat as a source of fuel the body will begin to slow down. In contrast, anaerobic exercise types include strength training, short distance sprinting, or any form of exercise where a short burst of intense exertion is performed. During anaerobic conditioning, glycogen is respired without oxygen and is a far less efficient process than aerobic conditioning.
For example, an unconditioned runner may "hit the wall" well short of completing a meter sprint. The bottom line is that in order for an activity to be considered and aerobic activity it must be able to increase your heart rate to your target heart rate and maintain that level for a minimum of 20 consecutive minutes.
In order to achieve an aerobic effect when exercising you will need to calculate your target heart rate. There are several methods that can be used to determine your target heart rate.
The first step in determining your target heart rate is to calculate your maximum heart rate. You maximum heart rate can be calculated by subtracting your age from For example, the maximum heart rate for an individual that is 30 years of age would be — 30 years of age. The next step is to determine at which percentage to calculate your target heart rate.
Below is a more formal example of how to calculate your target heart rate:. Although aerobic exercise is crucial to obtaining good health and fitness many aerobic activities fail to improve overall muscular strength and build lean muscle mass; especially in the upper body area. In addition, the metabolic pathways utilized in anaerobic metabolism i. Several individuals have suffered repetitive stress injuries from performing a specific aerobic exercise type over a long period of time.
The main types are: Brachials take blood to the wings. Pectorals deliver blood to the flight muscles pectoralis. The pulmonary arteries deliver blood to the lungs. Renal arteries deliver blood to the kidneys. Arrow, subsarcolemmal mitochondria; arrowhead, intermyofibrillar mitochondrion. Adaptation for high-altitude flight -- Bar-headed Geese Anser indicus migrate over the Himalayas at up to m elevation, but it is unclear how they sustain the high metabolic rates needed for flight in the severe hypoxia at these altitudes.
To better understand the basis for this physiological feat, Scott et al. Bar-headed Geese had more capillaries per muscle fiber than expected, and higher capillary densities and more homogeneous capillary spacing. Their mitochondria were also redistributed towards the sarcolemma cell membrane and adjacent to capillaries.
These alterations should improve O 2 diffusion capacity from the blood and reduce intracellular O 2 diffusion distances, respectively. Bar-headed Geese have, therefore, evolved for exercise in hypoxia by enhancing the O 2 supply to flight muscle. Most birds live and fly at relatively low altitudes, but some species live, migrate, or are occasionally found at higher altitudes Source: The transport of O 2 occurs along several steps of a cascading physiological pathway from atmospheric air to the mitochondria in tissue cells e.
The effectiveness of this pathway at transporting O 2 during hypoxia is imperative for flight at high altitudes, which depends upon several distinctive characteristics of birds in general and many unique features that have evolved in high flyers. The properties of O 2 utilization and ATP turnover in the flight muscle are also important to consider in high fliers Source: Some major veins in the avian circulatory system: The jugular veins drain the head and neck.
The brachial veins drain the wings. The pectoral veins drain the pectoral muscles and anterior thorax. The superior vena cavae or precavae drain the anterior regions of the body. The inferior vena cava or postcava drains the posterior portion of the body. The hepatic vein drains the liver. The hepatic portal vein drains the digestive system. The femoral veins drain the legs. The sciatic veins drain the hip or thigh regions. In most species, red blood cells are about 6 x 12 microns in size mammalian RBC's are typically 5.
Typical concentrations are 2. Avian red blood cells have a lifespan of days shorter than mammals, e. Red blood cells contain hemoglobin, the molecule responsible for transporting oxygen throughout the body, and are produced in the bone marrow.
However, many bird bones are pneumatic penetrated by air sacs and do not contain marrow. Hemopoietic bone marrow red-blood-cell-producing marrow is located in the radius, ulna, femur, tibiotarsus, scapula, furcula clavicles , pubis,and caudal vertebrae. Skeleton of a Rock Pigeon Columba livia showing the bones shaded that contain red-blood-cell-producing marrow, including the radius and ulna of the wing, femur and tibiotarsus of the leg, furcula and scapula of the pectoral girdle, pubis of the pelvic girdle, and caudal vertebrae.
Most other bones except for very small ones are pneumatized Schepelmann Under these conditions, natural selection favored the loss of nuclei in the red blood cells of mammals making the cells smaller and allowing capilaries to become even smaller in diameter and change to a biconcave shape increasing the amount of surface area and enhancing diffusion into and out of the red blood cells.
Birds, with their efficient respiratory system, evolved during the Jurassic when the oxygen content in the Earth atmosphere approached the present level, so there was no selective pressure to eliminate nuclei from their red blood cells or change in shape Gavrilov Thrombocytes are important in hemostasis blood clotting.
White blood cells play an important role in protecting birds from infectious agents such as viruses and bacteria. Birds have several types of white blood cells: Avian White Blood Cells The lymphocyte is the most numerous white blood cell. Lymphocytes are either T-lymphocytes formed in the thymus or B-lymphocytes formed in the bursa of Fabricius. B-lymphocytes produce antibodies; T-lymphocytes attack infected or abnormal cells.
The heterophil is the second most numerous WBC in most birds. Heterophils are phagocytic and use their enzyme-containing granules to lyse ingested materials. Heterophils are motile and can leave blood vessels to engulf foreign materials. Monocytes are motile cells that can migrate using ameboid movements. Monocytes are also phagocytic. The function is these cells is unclear. Scanning electron microscope view of bird thrombocytes adhering to a collagen-lined plate exposure to collagen causes bird thrombocytes, and mammalian platelets, to release chemicals that make them 'sticky'; the chemicals released by mammalian platelets are different from those released by bird thrombocytes and make platelets 'stickier' than thrombocytes.
Avian thrombocytes are larger than mammalian platelets, have a nucleus, and, unlike mammalian platelets, do not form 3-dimensional aggregates. Can birds have heart attacks and strokes? Platelet thrombi that form in the coronary and carotid arteries of humans can also cause common vascular diseases such as myocardial infarction 'heart attacks' and stroke and are the target of drugs used to treat these diseases. Birds have high-pressure cardiovascular systems like mammals, but have nucleated thrombocytes in their blood rather than platelets.
Avian thrombocytes are larger than mammalian platelets and are less 'sticky' because they release different chemicals than mammalian platelets when exposed to collagen connective tissue to which thrombocytes and platelets are exposed when there's a break in a blood vessel. When carotid arteries of mice are damaged, platelets form thrombi that can block blood flow check this video showing the response of human platelets when exposed to a plate covered with collagen ; similar damage to the carotid arteries of Budgerigars similar in size and speed and pressure of blood flow to the carotid arteries of mice did not cause the formation of thrombi check this video showing the response of chicken thrombocytes when exposed to a plate covered with collagen.
These results indicate that mammalian platelets, in contrast to avian thrombocytes, will form thrombi even in arteries where blood flow is rapid and under high pressure, an essential element in human cardiovascular diseases. Heart disease linked to evolutionary changes that may have protected early mammals from trauma. Covariation between relative brain mass of juvenile birds and relative mass of bursa of Fabricius in different bird species. Relative mass was calculated as residuals from a phylogenetically corrected regression of logtransformed organ mass on logtransformed body mass.
The lines are the linear regression lines for males and females, respectively From: B-lymphocytes, the cells that produce antibodies, are initially produced in the embryonic liver, yolk sac and bone marrow, then move through the blood to the bursa of Fabricius BF.
Within the BF, B-lymphocytes mature then migrate to other body tissues. The bursa is a blind sac that extends from the dorsal side of the cloaca, the common portal of the reproductive, urinary, and digestive systems. Within the bursas of young birds are extensive leaf-like folds composed of simple, columnar epidermis and a loose connective tissue with lots of blood vessels and lymph nodules. Atrophy of the BF typically occurs around the time of sexual maturation.
In birds, most of the Ig diversification occurs by gene conversion in the bursa of Fabricius. However, further Ig diversification is achieved by somatic hypermutation in secondary lymphoid organs From: B-lymphocytes produce three classes of antibodies after exposure to a disease organism: Ig M appears after days following exposure to a disease organism and then disappears by days. Ig A appears after 5 days following exposure.
This antibody is found primarily in the mucus secretions of the eyes, gut, and respiratory tract and provides "local" protection to these tissues. Antibodies do not have the capability to kill viruses or bacteria directly. Antibodies especially IgY perform their function by attaching to disease organisms like bacteria and blocking their receptors.
The disease organisms are then prevented from attaching to their target cells. The attached antibodies can also facilitate the destruction of pathogens by phagocytes. The T-lymphocytes include a more heterogeneous population than the B-cells.