Cometh Up As Wild Grass Defying Victorian Sister Narrative Conventions. - Literature Essay Samples

Christina Rossetti wrote â€Å"For there is no friend like a sister in calm or stormy weather; To cheer one on the tedious way, to fetch one if one goes astray, to lift one if one totters down, to strengthen whilst one stands.† Following the century of the â€Å"Rise of the Novel†, British women writers, who had been writing novels of Sensation or Manners, commonly used subplots of sister relationships to push their stories forward. Rhoda Broughton, is until this day, remembered as a sensational novelist with a knack for brazen heroines, who’s transgressive actions would eventually lead them to a conversion of passion to spirituality. Broughton’s work, thought of as wildly inappropriate due to her heroines exploring their sexuality fairly openly, was immoderately circulated amongst all classes. This popularity was mirrored in Broughton’s life. Although she never married, she was recognized for her parties and lively conversation. Cometh Up As a Flow er, her second novel published in 1867, presents Eleanora Lestrange (Nell), the youngest girl of a impoverished noble family, who is manipulated by her sister Dorothea (Dolly) into a loveless marriage. She falls in love with Richard M’Gregor (Dick), a soldier she instantly becomes infatuated with. Her frank expression of desires were the most controversial aspect of the novel in Victorian England, however, with time, it is the relationship between the naive Nell and her cold-hearted sister Dolly that has seemingly taken the forefront as the heart of the novel. Cometh Up As a Flower, is in appearance, following the long tradition of using a sister to the protagonist in order to direct her to an inevitable marriage. Broughton reverses the expectations by having Nell, the heroine, be manipulated into an unhappy marriage and having Dolly, an arguable antagonist, live out all her dreams. The story does not rely on sisterly love, but breaks the Victorian conventions, leading one to reflect on the evolving gender roles, place of women’s education and the desperation of women in the marriage market. The novel presents a pair of sisters embodying the Victorian archetypes: The fair sister and the dark sister. In Jane Austen’s Pride and Prejudice, the protagonist Elizabeth Bennett is compared to her sister, the ethereal, even-tempered Jane, throughout the novel. Elizabeth however, is a bluestocking and plain brunette, whom Mr Darcy goes as far as characterizing her appearance as â€Å"barely tolerable†. Broughton writes Dolly as the epitome of aristocratic beauty, defining her as â€Å"a very fair woman to look upon,† and going as far assimilating Dolly’s expressions as â€Å"nun-like, dovelike, Madonna-like.† She is akin to purity itself, whereas her sister has â€Å"red hair and a wide mouth.† Blonde beauty went back to Petrarchan sonnets, in which it not only symbolized virtue, it had an undertone of the unattainable. Red hair on the other hand, was attached to demonic connotations, and the lack of a soul. As Nell is the narrator, all th e descriptions are subjective and the reader is often led to suspect her unreliability. The narrative is paved with reflections of her comparisons such as â€Å"Dolly was beautiful, and the Lestranges had always been beautiful, and it was right she should go forth and be a credit to the old house, and I was ugly, and the Lestranges had never been ugly, and it was meet that I keep in the obscurity, for which I alone was calculated,† (49). She considers herself unattractive, feeble-minded as opposed to her fair, sociable and fashionable sister. Nell has been raised by her father, without her mother, or mother-figure. This had led to a permissive upbringing, which causes her passage to womanhood exceedingly difficult, as the rules that apply to child raised laxly would not translate well to expectations lady in age of marrying. She becomes heavily anxious in the presence of other ladies, stating she prefers the company of men, as the seem to be less judging of her. The perceived inferiority is in her constant comparison to Dolly, and the latter’s constant critic of her younger sister. Dolly on the opposite side of the spectrum, is a socially adept â€Å"femme fatale†. She is highly pragmatic of her position in life as woman in this society, a position is which she cannot afford to make a misstep, lest it make her already precarious prestige lose its last advantage. The Lestrange daughters, being impoverished, yet having an aristocratic background, leaves these women in the situation of marrying rich or resorting to working in undignified (in Dolly’s eyes) professions. Dolly, being aware of this reality, uses her charms to her advantage and does not show remorse when her actions come off as questionable. Nell sees this characteristic of Dolly as something she should learn. As much as she repeats her dislike of her sister, she cannot help but admiring her all the same. Their relationship dynamic is what fuels the plot. An advantageous marriage is the only option for Nell and Dolly to save their family name, causing the already tense dynamics between the sisters to bring out an unconventional â€Å"Sister Narrative†. Nell moves throughout the novel, quite naively unaware of her involvement is her family’s future. They are in a desperate predicament, as Dolly’s fiancà © passed away shortly before their nuptials. Nell seems oblivious to the extent of which her father and sister rely on her marriage to the aggressively average Sir Hugh. She is a teenage girl, who has fallen blindly in love with an inappropriate man. She had no sense of propriety as she repeatedly meets with Dick alone. Dolly is four years her senior, and infinitely more jaded. Her personality is split by a flirtatious, worldly socialite in the Public Sphere and a cold-blooded (not so) mother-figure. As an elder sister with much knowledge of society to impart on to Nell, Dolly is disinterested in teaching her, cons idering it to be but one step above working as a governess. She does not miss an opportunity to critic Nell’s appearance, to the extent of greeting her after a long absence with â€Å"How are you? Much the same as usual, I see —hair arranged with a pitchfork and dress with a view for ventilation,† (114). One could argue that Dolly’s animosity could be fuelled by jealousy of her younger sister as she approaches spinsterhood rapidly. Others may defend Dolly as having Nell’s best interest at heart, albeit with questionable methods, however, she had also been left motherless since childhood, therefore creating a gaping whole in her education in empathy. One must add that Nell is not entirely interested in Dolly’s mentorship, but prefers to know how she learned this, and read up on the subject herself. She is too fond of her freedom to abide by the many social restrictions that her elder sister revels in. Nonetheless Dolly becomes the novelâ€⠄¢s main antagonist when she discovers her sister’s attraction to Dick, a union that would cause a scandal and deter Sir Hugh from marrying her. This would destroy their reputation, the only semblance of dignity they had, but most importantly too Dolly, this would destroy all her prospects. She then sets herself on a mission to create as many obstacles as possible, starting with simple flirtation to redirect Dick’s affections, escalating to her forging Nell’s signature in a letter to Dick, asking him to keep his distances from her. This would be considered a grave offence, and when Nell finds out, after her reluctant marriage to Sir Hugh, she threatens to expose her. Although she is aware her crime could cause her engagement to a wealthy aristocrat to be called off, she shows no sign of remorse for her actions. This leads to Nell coming to the realization that her revenge would not adjudicate her from betraying her own sister, and it would not mend her broken he art. She decides to forgive her, resigns herself to an unhappy yet advantageous marriage and Dolly is wed into the situation she had been striving for all along. Towards the end of the novel, as per convention, both sisters are in respectable situations, despite the fact that they both arrived to this point via sensational actions. This suggests a provocative premise, in which Broughton may be arguing the idea that traditional values are inevitable, and perhaps that resisting this passage to adulthood is to the detriment of the soul. Following Dolly’s marriage, and Nell learning that Dick has passed away, the novels skips two years to which Nell is now dying. She has become deeply religious, suggesting this novel as a conversion narrative. She writes â€Å"Since then, I have been sorry for my sin; at least I have tried to be,† (330). Nell does show signs of acknowledgement of her pasts transgressions with propriety though she longs to see Dick when her time comes. This appears as an unconvincing conversion, as Nell is also dying of consumption, an illness long considered to be caused by a broken heart, due to the rapid weight lo ss. This gave an impression of people withering away and being consumed by their feelings, suggesting her heart is not as pious as she may want to appear. Dolly, despite her machiavellian actions, is the one who not only survives, but is rewarded with all the superficialities she had wanted and most importantly, she survives knowing her sister had forgiven her long ago. Christina Rossetti writes her version of this convention of sisterhood in her children’s poem â€Å"Goblin Market†. Her premise, although different from most sister narratives that end with weddings, she does not write marriage as the core of her protagonists’ happiness. It is Lizzie’s selfless actions of love that save her sister Laura from becoming a fallen woman after tasting the Goblins’ fruit. Cometh Up As a Flower does a similar take on the sisterhood being much more important than the romance. Broughton makes an interesting paradox in which she uses these two archetypes of si sters, the rebel and the angel, pushes them to their extremes to highlight the flaws in the idealization of sisterhood in a world in which all women are rivals in the marriage market. They are but two sides of the same coin. This rings even more true for sisters, considering they would likely have similar dowries and would be bringing the prestige of their family name to the marriage. Such circumstances would entail the sisters being distinguished by their beauty and mannerism. Although in this case, the sisters are not competing for the same match, the constant comparison is a recurring theme. Dolly and Nell exchange insults, and attempt to manipulate each other to meet their goals. Broughton takes the convention of sisterly love in a courtship setting, but exploits the realities and not the romanticized version that influenced the women of the time. She also takes the opportunity to make a serious commentary on the crucial aspect of the public sphere in courtship, juxtaposing the many masks a woman must wear in order to be successful. Dolly is the epitome of a social butterfly, but who’s selfish disposition weighs heavily on her entourage at home. Nell is at her most free at home, but finds social gathering, especially in the presence of other women to be source of great anxiety. The Lestrange sisters therefore fail to wear al the masks necessary to be the quintessential Victorian woman, something most women would have probably found some source of relief, as no one could be perfect at all times. It does seem as though Broughton takes a stance on which mask one should prioritize. Sisterly love in a time of radical social shifts is dubitable, albeit not unimaginable. The Victorian Era, is one that follows violent decades of decolonization, revolution and scientific progress. The aristocracy, unless they made the progressive choice of joining the industrial revolution, often found their wealth depleted. This made the daughters of these families particularly vulnerable and highly dependent on a great match if they were to secure a prosperous future. Nell is naive in the way that she priorities her passion and desires until womanhood is forced unto her when her father is on his death bed, leading her to realize just how important her union with Sir Hugh would be. Dolly on the other hand, is not concerned by developing a meaningful relationship with her sister, and manipulates her and Dick expertly in order to achieve her goals. Broughton, draws on this desperate reality, one she may have felt close to due to her being a spinster living with her married sisters, t o emphasize just how the education of women was severely flawed and the lengths to which their environment pushes them beyond the limits of morality. Even though Nell is the one who may seem the indisputable victim with a tragic ending, whereas Dolly may come off as the mercenary villain, one must remember the context. In a Victorian milieu, Nell’s end is a punishment for her transgressions of passions, and Dolly’s actions are not only in the best interest of her future, they are in the best interest of her sister’s future and their family’s as well. Dolly followed the rules, Dolly reaped the massive rewards. In her book Sororophobia: Differences Among Women in Literature and Culture, Helena Michie studies female dynamics in Victorian Literature. She writes â€Å"Feminine passivity will reap the very rewards that female aggression seeks and fails to achieve†. Dorothea Lestrange would beg to differ. Works Cited: Broughton, Rhoda. Cometh Up As a Flower. Broadview Editions, 2010. Faber, Lindsay. Chapter 13 : One Sisters Surrender. Victorian Sensations: Essays on a Scandalous Genre. Columbus: Ohio State UP, 2006. 149-59. Print. Hallum, Kirby-Jane. Aestheticism and the Marriage Market in Victorian Popular Fiction: The Art of Female Beauty Mermin, Dorothy. Heroic Sisterhood in Goblin Market Victorian Poetry 21.2 (1983): 107-18. Web. Rossetti, Christina Georgina. Goblin Market and Selected Poems. Whitefish, MT: Kessinger Pub., 2005. Print.

Qantassaurus - Facts and Figures

Name: Qantassaurus (Greek for Qantas lizard); pronounced KWAN-tah-SORE-us Habitat: Woodlands of Australia Historical Period: Early Cretaceous (115 million years ago) Size and Weight: About six feet long and 100 pounds Diet: Plants Distinguishing Characteristics: Small size; long legs; bipedal posture; round, blunt head with large eyes About Qantassaurus Like its close relative, the equally unpronounceable Leaellynasaura, Qantassaurus lived in Australia during a time (the early Cretaceous period) when that continent was much further south than it is today, meaning this dinosaur thrived in wintry conditions that would have killed most its kind. That explains the relatively slender size of Qantassaurus--there wouldnt have been enough vegetation in its harsh climate to supply a multi-ton herbivore--as well as its relatively large eyes, which it presumably needed to see clearly in the near-Antarctic dusk, and its longer-than-usual legs, with which it could outrun hungry predators. This ornithopod dinosaur was also distinguished by its unusually blunt face; Qantassaurus had slightly fewer teeth than its plant-eating cousins from further north. By the way, Qantassaurus, named after Australias Qantas Airlines, isnt the only prehistoric animal to pay homage to a multinational corporation; witness the ancient amphibian Fedexia, which was discovered near a Federal Express depot, as well as Atlascopcosaurus, which honors a manufacturer of mining equipment. (The husband-and-wife team that discovered Qantassaurus, Tim and Patricia Vickers-Rich, are known for bestowing unusual names on their dinosaurs; for example, Leaellynasaura was named after their daughter, and the bird mimic dinosaur Timimus after their son.)

Garden Of The Gods A State Park - 2133 Words

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The park offers guided horseback ri des where anyone from a novice to an accomplished rider can enjoy the park s views and a slightly faster pace. Trained guides offer not only the phenomenal tour of the state park, but also insightful historic information that any tourist will find interesting. In addition to walking trails and horseback riding, the park is a dreamland for rock climbers. With easy starter rocks that even a child can climb, it is outdoor fun for the whole family. There are also rocks towering over the park thatShow MoreRelatedColorado : The Mountain National Park1011 Words   |  5 Pagesgeological wonder, and natural beauty, Colorado has all that to offer. Colorado is the state where The Rocky Mountain National Park was born. The geological and natural wonders of the park leave many guest visiting the area coming back for more every year. This state is also gifted with one of the biggest attraction in America: The Grand Canyon. 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The function of the human body - Free Essay Example

Sample details Pages: 24 Words: 7348 Downloads: 2 Date added: 2017/06/26 Category Statistics Essay Did you like this example? Exercise represents one the highest levels of extreme stresses to which the body can be exposed. Exercise physiology is the study of the function of the human body during various acute and chronic exercise conditions. These effects are significant during both short, high intensity exercise as well as with prolonged strenuous exercise such as done in endurance sports like marathons, ultramarathons, and road bicycle racing.In exercise, the liver generates extra glucose, while increased cardiovascular activity by the heart, and respiration by the lungs, provides an increased supply of oxygen. Don’t waste time! Our writers will create an original "The function of the human body" essay for you Create order When exercise is very prolonged and strenuous, a decline, however, can occur in blood levels of glucose. In some individuals, this might even cause hypoglycemia and hypoxemia. There can also be cognitive and physical impairments due to dehydration. Another risk is low plasma sodium blood levels.Prolonged exercise is made possible by the human thermoregulation capacity to remove exercise waste heat by sweat evaporation. This capacity evolved to enable early humans after many hours of persistence hunting to exhaust game animals that cannot remove so effectively exercise heat from their body. In general, the exercise-related measurements established for women follow the same general principles as those established for men, except for the quantitative differences caused by differences in body size, body composition, and levels of testosterone. In women, the values of muscle strength, pulmonary ventilation, and cardiac output (all variables related with muscle mass) are generally 60-75% of the exercise physiology values recorded in men. When measured in terms of strength per square centimeter, the female muscle can achieve the same force of contraction as that of a male. The functions of muscle tissues assume roles in homeostasis, as follows: Excitability Property of receiving and responding to stimuli such as the following: Neurotransmitters: Acetylcholine (ACh) stimulates skeletal muscle to contract, electrical stimuli: Applying electrical stimuli between cardiac and smooth muscle cells causes the muscles to contract, Applying a shock to skeletal muscle causes contraction, Hormonal stimuli: Oxytocin stimulates smooth muscle in the uterus to contract during labor.Contractility Ability to shorten. Extensibility Ability to stretch without damageElasticity Ability to return to original shape after extensionThrough contraction, muscle provides motion of the body (skeletal muscle), motion of blood (cardiac muscle), and motion of hollow organs such as the uterus, esophagus, stomach, intestines, and bladder (smooth muscle).Muscle tissue also helps maintain posture and produce heat. A large amount of body heat is produced by metabolism and by muscle con traction. Muscle contraction during shivering warms the body. Skeletal muscle consists of fibers (cells). These cells are up to 100 ÂÂ µm in diameter and often are as long as the muscle. Each contains sarcoplasm (cytoplasm) and multiple peripheral nuclei per fiber. Skeletal muscle is actually formed by the fusion of hundreds of embryonic cells. Other cell structures include the following:Each fiber is covered by a sarcolemma (plasma membrane). The sarcoplasmic reticulum (smooth endoplasmic reticulum) stores calcium, which is released into the sarcoplasm during muscle contraction. Transverse tubules (T tubules), which are extensions of the sarcolemma that penetrate cells, transmit electrical impulses from the sarcolemma inward, so electrical impulses penetrate deeply into the cell. Besides conducting electricity along their walls, T tubules contain extracellular fluid rich in glucose and oxygen.The sarcoplasm of fiber is rich in glycogen (glucose polymer) granules and myoglobin (oxygen-storing protein). It also is rich in mitochondria. Eac h fiber contains hundreds to thousands of rodlike myofibrils, which are bundles of thin and thick protein chains termed myofilaments. From a cross-sectional view of a myofibril, each thick filament is surrounded by a hexagonal array of 6 thin filaments. Each thin filament is surrounded by a triangular array of thick filaments.myofilaments are composed of 3 proteins: actin, tropomyosin, and troponin. Thick myofilaments consist of bundles of approximately 200 myosin molecules. Myosin molecules look like double-headed golf clubs (both heads at the same end). The heads of the golf clubs are called myosin heads; they are also called cross-bridges because they link thick and thin filaments during contraction. They contain actin andadenosine triphosphate (ATP) binding sites. Myosin heads project out from the thick filaments, allowing them to bind to the thin filaments during contraction. Actin is a long chain of multiple globular proteins, similar in shape to kidney beans. Each globular su bunit contains a myosin-binding site. Tropomyosin is a long strand of protein that covers the myosin-binding sites on actin when the muscle is relaxed. Troponin is a polypeptide complex that binds to tropomyosin, helping to position it over the myosin-binding sites on actin. During muscle contraction, calcium binds troponin, which causes tropomyosin to roll off of the myosin binding sites on actin. A muscle action potential travels over sarcolemma and enters the T tubules, causing the sarcoplasmic reticulum to release calcium into the sarcoplasm. This triggers the contractile process.Myosin cross-bridges pull on the actin myofilaments, causing the thin myofilaments of a sarcomere to slide toward the centers of the H zones.Deep fascia is a broad band of dense irregular connective tissue beneath and around muscle and organs. Deep fascia is different from superficial fascia, which is loose areolar connective tissue.Other connective-tissue components (all are extensions of deep fascia) include epimysium, which covers the entire muscle; perimysium, which penetrates into muscle and surrounds bundles of fibers called fascicles; and endomysium, which is delicate, barely visible, loose areolar tissue covering individual fibers (ie, individual cells).Tendons and aponeuroses are tough extensions of epimysium, perimysium, and endomysium. Tendons and aponeuroses are made of dense regular c onnective tissue and attach the muscle to bone or other muscle. Aponeuroses are broad, flat tendons. Tendon sheaths contain synovial fluid and enclose certain tendons. Tendon sheaths allow tendons to slide back and forth next to each other with lower friction. Tenosynovitis is inflammation of the tendon sheaths and tendons, especially those of the wrists, shoulders, and elbows. Tendons are not contractile and not very stretchy; furthermore, they are not very vascular and they heal poorly. Nerves convey impulses for muscular contraction. Nerves are bundles of nerve cell processes. Each nerve cell process (ie, axon) divides at its tip into a few to 10,000 branches called telodendria. At the end of each of these branches is an axon terminal that is rich in neurotransmitters.Blood provides nutrients and oxygen for contraction. An artery and a vein usually accompany a nerve that penetrates skeletal muscle. Arteries in muscles dilate during active muscular activity, thus increasing the supply of oxygen and glucose.A motor nerve is a bundle of axons that conducts nerve impulses away from the brain or spinal cord toward muscles. Each axon transmits an action potential (ie, nerve impulse), which is a burst of electricity. The nerve impulse travels along the axons at a steady rate, like fire travels along a fuse; however, nerve impulses travel extremely fast. Each axon has 4-2000 or more branches (ie, telodendria), with an average of 150 telodendria. Each separate branch suppl ies a separate muscle cell. Thus, if an axon has 10 branches, it supplies 10 muscle fibers. Small motor units are for fine control of muscles; large motor units are for muscles that do not require such fine control.The neuromuscular junction is made of an axon terminal and the portion of the muscle fiber sarcolemma it nearly touches (called the motor endplate). The neurotransmitter released at the neuromuscular junction in skeletal muscle is ACh. The motor endplate is rich in thousands of ACh receptors; the receptors are integral proteins containing binding sites for ACh and sodium channels. Nerve impulse (action potential) reaches the axon terminal, which triggers calcium influx into the axon terminal.Calcium influx causes synaptic vesicles to release ACh via exocytosis. ACh diffuses across synaptic cleft.ACh binds to theACh receptor on the sarcolemma. Succinylcholine, a drug used to induce paralysis during surgery, binds to ACh receptors more tightly than ACh. Succinylcholine initially causes some depolarization, but then itbinds to the receptor, preventing ACh from binding. Therefore, it blocks the muscles stimulation by ACh, causing paralysis. Another drug that acts in a similar fashion is curare. These drugs do not cause pain relief or unconsciousness; thus, they are combined with other drugs during surgery.When ACh binds the receptor, it opens chemically regulated ion channels, which are sodium channels through the receptor molecule. Sodium, which is in high concentration outside cells and in low concentration inside cells, rushes into the cell through the channels.The cell, whose resting membrane potential along the inside of the membrane is negative when comparedwith the outside of the membrane, becomes positively charged along the inside of t he membrane when sodium (a positive ion) rushes in. This change from a negative charge to a positive charge along the inner membrane is termed depolarization.The depolarization of one region of the sarcolemma (the motor endplate) initiates an action potential, which is a propagating wave of depolarization that travels (propagates) along the sarcolemma. Regions of membrane that become depolarized rapidly restore their proper ionic concentrations along their inner and outer surfaces in a process termed repolarization. (This process of depolarization, propagation, and repolarization is similar to dominoes that topple each other but also spring back into the upright position shortly afterward.)The action potential also propagates along the membrane lining the T tubules entering the cell.This action potential traveling along the T tubules causes the sarcoplasmic reticulum to release calcium into sarcoplasm.Calcium binds with troponin, causing it to pull on tropomyosin to change its orien tation, exposing myosin-binding sites on actin.An ATPase, which also functions as a myosin cross-bridging protein, splits ATP into adenosine diphosphate (ADP) + phosphate (P) in the previous contraction cycle. This energizes the myosin head. The energized myosin head, or cross-bridge, combines with myosin-binding sites on actin.Power stroke occurs. The attachment of the energized cross-bridge triggers a pivoting motion (ie, power stroke) of the myosin head. During the power stroke, ADP and P are released from the myosin cross-bridge. The power stroke causes thin actinmyofilaments to slide past thick myosin myofilaments toward the center of the A bands.ATP attaches to the myosin head again, allowing it to detach from actin. (In rigor mortis, an ATP deficiency occurs. Cross-bridges remain, and the muscles are rigid.)ATP is broken down to ADP and P, which cocks the myosin head again, preparing it to perform another power stroke if needed. Repeated detachment and reattachment of the cross-bridges results in shortening without much increase in tension during the shortening phase (isotonic contraction) or results in increased tension without shortening (isometric contraction).Release of the enzyme acetylcholinesterasein the neuromuscular junction destroys ACh and stops the generation of a muscle action potential. Calcium is taken back up (resequestered) in the sarcoplasmic reticulum, and myosin cross-bridges separate. ATP is required to separate myosin-actin cross-bridges. The muscle fiber resumes its resting state. The chemical energy that fuels muscular activities is ATP. For the first 5 or 6 seconds of muscle power, muscular activity can depend on the ATP that is already present in the muscle cells. Beyond this time, new amounts of ATP must be formed to enable the activation of muscular contractions that are needed to support longer and more vigorous physical activities. For activities that require a quick burst of energy that cannot be supplied by the ATP present in the muscle cells, the next 10-15 seconds of muscle power can be provided through the bodys use of the phosphagen system, which uses a substance called creatine phosphate to recycle ADP into ATP.4 For longer and more intense periods of physical activity, the body must rely on systems that break down the sugars (glucose) to produce ATP. The complete breakdown of glucose occurs in 2 ways: through anaerobic respiration (does not use oxygen) and through aerobic respiration (occurs in the presence of oxygen). The anaerobic use of gluc ose to form ATP occurs as the body increases its muscle use beyond the capability of the phosphagen system to supply energy. In particular, the glycogen lactic acid system, through its anaerobic breakdown of glucose, provides approximately 30-40 seconds more of maximal muscle activity. For this system, each glucose molecule is split into 2 pyruvic acid molecules, and energy is released to form several ATP molecules, providing the extra energy. Then, the pyruvic acid partially breaks down further to produce lactic acid. If the lactic acid is allowed to accumulate in the muscle, one experiences muscle fatigue. At this point, the aerobic system must activate.The aerobic system in the body is used for sports that require an extensive and enduring expenditure of energy, such as a marathon race. Endurance sports absolutely require aerobic energy. A large amount of ATP must be provided to muscles to sustain the muscle power needed to perform such events without an excessive production of l actic acid. This can only be accomplished when oxygen in the body is used to break down the pyruvic acid (that was produced anaerobically) into carbon dioxide, water, and energy by way of a very complex series of reactions known as the citric acid cycle. This cycle supports muscle usage for as long as the nutrients in the body last. The breakdown of pyruvic acid requires oxygen and slows or eliminates the accumulation of lactic acid. In summary, the 3 different muscle metabolic systems that supply the energy required for various activities are as follows: Phosphagen system (for 10- to 15-sec bursts of energy)Glycogen lactic acid system (for another 30-40 sec of energy)Aerobic system (provides a great deal of energy that is only limited by the bodys ability to supply oxygen and other important nutrients) Many sports require the use of a combination of these metabolic systems. By considering the vigor of a sports activity and its duration, one can estimate very closely which of the en ergy systems are used for each activity. During muscular exercise, blood vessels in muscles dilate and blood flow is increased in order to increase the available oxygen supply. Up to a point, the available oxygen is sufficient to meet the energy needs of the body. However, when muscular exertion is very great, oxygen cannot be supplied to muscle fibers fast enough, and the aerobic breakdown of pyruvic acid cannot produce all the ATP required for further muscle contraction. During such periods, additional ATP is generated by anaerobic glycolysis. In the process, most of the pyruvic acid produced is converted to lactic acid. Although approximately 80% of the lactic acid diffuses from the skeletal muscles and is transported to the liver for conversion back to glucose or glycogen, some lactic acid accumulates in muscle tissue, making muscle contraction painful and causing fatigue. Ultimately, once adequate oxygen is available, lactic acid must be catabolized completely into carbon dioxide and water. After exercise has stopped, extra oxygen is required to metabolize lactic acid; to replenish ATP, phosphocreatine, and glycogen; and to replace (pay back) any oxygen that has been borrowed from hemoglobin, myoglobin (an iron-containing substance similar to hemoglobin that is found in muscle fibers), air in the lungs, and body fluids. The additional oxygen that must be taken into the body after vigorous exercise to restore all systems to their normal states is called oxygen debt. The debt is paid back by labored breathing that continues after exercise has stopped. Thus, the accumulation of lactic acid causes hard breathing and sufficient discomfort to stop muscle activity until homeostasis is restored.5 Eventually, muscle glycogen must also be restored. Restoration of muscle glycogen is accomplished through diet and may take several days, depending on the intensity of exercise. The maximum rate of oxygen consumption during the aerobic catabolism of pyruvic acid is called maximal oxygen uptake. Maximal oxygen uptake is determined by sex (higher in males), age (highest at approximately age 20 y), and size (increases with body size). Highly trained athletes can have maximal oxygen uptakes that are twice that of average people, probably owing to a combination of genetics and training. As a result, highly trained athletes are capable of greater muscular activity without increasing their lactic acid production and have lower oxygen debts, which is why they do not become short of breath as readily as untrained individuals. The best examples of light exercise are walking and light jogging. The muscles that are recruited during this type of exercise are those that contain a large amount of type I muscle cells, and, because these cells have a good blood supply, it is easy for fuels and oxygen to travel to the muscle. ATP consumption makes ADP available for new ATP synthesis. The presence of ADP (and the resulting synthesis of ATP) simulates the movement of hydrogen (H+) into the mitochondria; this, in turn, reduces the proton gradient and thus stimulates electron transport. The hydrogen on the reduced form of nicotinamide adenine dinucleotide (NADH) is used up, nicotinamide adenine dinucleotide (NAD) becomes available, and fatty acids and glucose are oxidized. Incidentally, the calcium released during contraction stimulates the enzymes in the Krebs cycle and stimulates the movement of the glucose transporter 4 (GLUT-4) from inside of the muscle cell to the cell membrane. Both these exercise-induced respo nses augment the elevation in fuel oxidation caused by the increase in ATP consumption. An increase in the pace of running simply results in an increased rate of fuel consumption, an increased fatty acid release, and, therefore, an increase in the rate of muscle fatty acid oxidation. However, if the intensity of the exercise increases even further, a stage is reached in which the rate of fatty acid oxidation becomes limited. The reasons why the rate of fatty acid oxidation reaches a maximum are not clear, but it is possible that the enzymes in the beta-oxidation pathway are saturated (ie, they reach a stage in which their maximal velocity [Vmax] is less than the rate of acetyl-coenzyme A [acetyl-CoA] consumption in the Krebs cycle). Alternatively, it may be that the availability of carnitine (the chemical required to transport the fatty acids into the mitochondria) becomes limited. Whatever the reason, the consequence is that as the pace rises, the demand for acetyl-CoA cannot be me t by fatty acid oxidation alone. The accumulation of acetyl-CoA that was so effective at inhibiting the oxidation of glucose is no longer present, so pyruvate dehydrogenase starts working again and pyruvate is converted into acetyl-CoA. In other words, more of the glucose that enters the muscle cell is oxidized fully to carbon dioxide. Therefore, the energy used during moderate exercise is derived from a mixture of fatty acid and glucose oxidation. As the intensity of the exercise increases even further (ie, running at the pace of middle-distance races), the rate at which the muscles can extract glucose from the blood becomes limited. In other words, the rate of glucose transport reaches Vmax, either because the blood cannot supply the glucose fast enough or the number of GLUT-4s becomes limited. ATP generation cannot be serviced completely by exogenous fuels, and ATP levels decrease. Not only does this stimulate phosphofructokinase, it also stimulates glycogen phosphorylase. This m eans that glycogen stored within the muscle cells is broken down to provide glucose. Therefore, the fuel mix during strenuous exercise is composed of contributions from blood-borne glucose and fatty acids and from endogenously stored glycogen.Being fit (biochemically speaking) means that the individual has a well-developed cardiovascular system that can efficiently supply nutrients and oxygen to the muscles. Fit people have muscle cells that are well perfused with capillaries (ie, they have a good muscle blood supply). Their muscle cells also have a large number of mitochondria, and those mitochondria have a high activity of Krebs cycle enzymes, electron transport carriers, and oxidation enzymes. Individuals who are unfit must endure the consequences of a poorer blood supply, fewer mitochondria, less electron transport units, a lower activity of the Krebs cycle, and poorer activity of beta-oxidation enzymes. To generate ATP in the mitochondria, a steady supply of fuel and oxygen and decent activity of the oxidizing enzymes and carriers are needed. If any of these components are lacking, the rate at which ATP can be produced by mitochondria is compromised. Under these circumstances, the production of ATP by aerobic means is not sufficient to provide the muscles with sufficient ATP to sustain contractions. The result is anaerobic ATP generation using glycolysis. Increasing the flux through glycolysis but not increasing the oxidative consumption of the resulting pyruvate increases the production of lactate. The purpose of respiration is to provide oxygen to the tissues and to remove carbon dioxide from the tissues. To accomplish this, 4 major events must be regulated, as follows: Pulmonary ventilation. Diffusion of oxygen and carbon dioxide between the alveoli and the blood, Transport of oxygen and carbon dioxide in the blood and body fluids and to and from the cells, Regulation of ventilation and other aspects of respiration: Exercise causes these factors to change, but the body is designed to maintain homeostasisWhen one goes from a state of rest to a state of maximal intensity of exercise, oxygen consumption, carbon dioxide formation, and total pulmonary and alveolar ventilation increase by approximately 20-fold. A linear relationship exists between oxygen consumption and ventilation. At maximal exercise, pulmonary ventilation is 100-110 L/min, whereas maximal breathing capacity is 150-170 L/min. Thus, the maximal breathing capacity is approximately 50% greater than the actual pulmo nary ventilation during maximal exercise. This extra ventilation provides an element of safety that can be called on if the situation demands it (eg, at high altitudes, under hot conditions, abnormality in the respiratory system). Therefore, the respiratory system itself is not usually the most limiting factor in the delivery of oxygen to the muscles during maximal muscle aerobic metabolism. VO2 max is the rate of oxygen consumption under maximal aerobic metabolism. This rate in short-term studies is found to increase only 10% with the effect of training. However, that of a person who runs in marathons is 45% greater than that of an untrained person. This is believed to be partly genetically determined (eg, stronger respiratory muscles, larger chest size in relation to body size) and partly due to long-term training. Oxygen diffusing capacity is a measure of the rate at which oxygen can diffuse from the alveoli into the blood. An increase in diffusing capacity is observed in a state of maximal exercise. This results from the fact that blood flow through many of the pulmonary capillaries is sluggish in the resting state. In exercise, increased blood flow through the lungs causes all of the pulmonary capillaries to be perfused at their maximal level, providing a greater surface area through which oxygen can diffuse into the pulmonary capillary blood. Athletes who require greater amounts of oxygen per minute have been found to have higher diffusing capacities, but the exact reason why is not yet known. Although one would expect the oxygen pressure of arterial blood to decrease during strenuous exercise and carbon dioxide pressure of venous blood to increase far above normal, this is not the case. Both of these values remain close to normal. Stimulatory impulses from higher centers of the brain and from joint and muscle proprioceptive stimulatory reflexes account for the nervous stimulation of the respiratory and vasomotor center that provides almost exactly the p roper increase in pulmonary ventilation to keep the blood respiratory gases almost normal. If nervous signals are too strong or weak, chemical factors bring about the final adjustment in respiration that is required to maintain homeostasis. Regular exercise makes the cardiovascular system more efficient at pumping blood and delivering oxygen to the exercise muscles. Releases of adrenaline and lactic acid into the blood result in an increase of the heart rate (HR). Basic definitions of terms are as follows:VO2 equals cardiac output times oxygen uptake necessary to supply oxygen to muscles. The Fick equation is the basis for determination of VO2. Exercises increase some of the different components of the cardiovascular system, such as stroke volume (SV), cardiac output, systolic blood pressure (BP), and mean arterial pressure. A greater percentage of the cardiac output goes to the exercising muscles. At rest, muscles receive approximately 20% of the total blood flow, but during exercise, the blood flow to muscles increases to 80-85%. To meet the metabolic demands of skeletal muscle during exercise, 2 major adjustments to blood flow must occur. First, cardiac output from the heart must increase. Second, blood flow from in active organs and tissues must be redistributed to active skeletal muscle. Generally, the longer the duration of exercise, the greater the role the cardiovascular system plays in metabolism and performance during the exercise bout. An example would be the 100-meter sprint (little or no cardiovascular involvement) versus a marathon (maximal cardiovascular involvement). The cardiovascular system helps transport oxygen and nutrients to tissues, transport carbon dioxide and other metabolites to the lungs and kidneys, and distribute hormones throughout the body. The cardiovascular system also assists with thermoregulation.The pumping of blood by the heart requires the following 2 mechanisms to be efficient:Alternate periods of relaxation and contraction of the atria and ventriclesCoordinated opening and closing of the heart valves for unidirectional flow of blood The cardiac cycle is divided into 2 phases: ventricular diastole and ventricular systole.This phase begins with the opening of the atrioventricular (AV) valves. The mitral valve (located between the left atrium and left ventricle) opens when the left ventricular pressure falls below the left atrial pressure, and the blood from left atrium enters the left ventricle.Later, as the blood continues to flow into the left ventricle, the pressure in both chambers tends to equalize.At the end of the d iastole, left atrial contractions cause an increase in left atrial pressure, thus again creating a pressure gradient between the left atrium and ventricle and forcing blood into the left ventricle.Ventricular systole begins with the contraction of the left ventricle, which is caused by the spread of an action potential over the left ventricle. The contraction of the left ventricle causes an increase in the left ventricular pressure. When this pressure is higher than the left atrial pressure, the mitral valve is closed abruptly.The left ventricular pressure continues to rise after the mitral valve is closed. When the left ventricular pressure rises above the pressure in the aorta, the aortic valve opens. This period between the closure of the mitral valve and the opening of the aortic valve is called isovolumetric contraction phase.The blood ejects out of the left ventricle and into the aorta once the aortic valve is opened. As the left ventricular contraction is continued, 2 process es lead to a fall in the left ventricular pressure. These include a decrease in the strength of the ventricular contraction and a decrease in the volume of blood in the ventricle.When the left ventricular pressure falls below the aortic pressure, the aortic valve is closed. After the closure of the aortic valve, the left ventricular pressure falls rapidly as the left ventricle relaxes. When this pressure falls below the left atrial pressure, the mitral valve opens and allows blood to enter left ventricle. The period between the closure of the aortic valve closure and the opening of the mitral valve is called isovolumetric relaxation time. Right-sided heart chambers undergo the same phases simultaneously. Most of the work of the heart is completed when ventricular pressure exists. The greater the ventricular pressure, the greater the workload of the heart. Increases in BP dramatically increase the workload of the heart, and this is why hypertension is so harmful to the heart.Arterial BP is the pressure that is exerted against the walls of the vascular system. BP is determined by cardiac output and peripheral resistance. Arterial pressure can be estimated using a sphygmomanometer and a stethoscope. The reference range for males is 120/80 mm Hg; the reference range for females is 110/70 mm Hg. The difference between systolic and diastolic pressure is called the pulse pressure. The average pressure during a cardiac cycle is called the mean arterial pressure (MAP). MAP determines the rate of blood flow through the systemic circulation.During rest, MAP = diastolic BP + (0.33 X pulse pressure). For example, MAP = 80 + (0.33 X [120-80]), MAP = 93 mm Hg. During exercise, MAP = diastolic BP + (0.50 X pulse pressure). For example, MAP = 80 + (0.50 X [160-80]), MAP = 120 mm Hg. The heart has the ability to generate its own electrical activity, which is known as intrinsic rhythm. In the healthy heart, contraction is initiated in the sinoatrial (SA) node, which is often called the hearts pacemaker. If the SA node cannot set the rate, then other tissues in the heart are able to generate an electrical potential and establish the HR.The parasympathetic nervous system and the sympathetic nervous system affect a personsHR. Parasympathetic nervous system: The vagus nerve originates in the medulla and innervates the SA and AV nodes. The nerve releases ACh as the neurotransmitter. The response is a decrease in SA node and AV node activity, which causes a decrease in HR. Sympathetic nervous system: The nerves arise from the spinal cord and innervate the SA node and ventricular muscle mass. The nerves release norepinephrine as the neurotransmitter. The response is an increase in HR and a force of contraction of the ventricles.At rest, sympathetic and parasympathetic n ervous stimulation are in balance. During exercise, parasympathetic stimulation decreases and sympathetic stimulation increases. Several factors can alter sympathetic nervous system input.Baroreceptors are groups of neurons located in the carotid arteries, the arch of aorta, and the right atrium. These neurons sense changes in pressure in the vascular system. An increase in BP results in an increase in parasympathetic activity except during exercise, when the sympathetic activity overrides the parasympathetic activity. Chemoreceptors are groups of neurons located in the arch of the aorta and the carotid arteries. These neurons sense changes in oxygen concentration. When oxygen concentration in the blood is decreased, parasympathetic activity decreasesand sympathetic activity increases. Temperature receptors are neurons located throughout the body. These neurons are sensitive to changes in body temperature. As temperature increases, sympathetic activity increases to cool the body and to reduce internal core temperature.SV is controlled by end-diastolic volume, average aortic BP, and the strength of ventricular contraction. End-diastolic volume: This is often referred to as the preload. If the end-diastolic volume increases, the SV increases. With an increased end-diastolic volume, a slight stretching of the cardiac muscle fibers occurs, which increases the force of contraction. Average aortic BP: This is often referred to as the afterload. The BP in the aorta represents a barrier to the blood being ejected from the heart. The SV is inversely proportional to the aortic BP. During exercise, the afterload is reduced, which allows for an increase in SV. Strength of ventricular contraction: Epinephrine and norepinephrine can increase the contractility of the heart by inc reasing the calcium concentration within the cardiac muscle fiber. Epinephrine and norepinephrine allow for greater calcium entry through the calcium channels in cardiac muscle fiber membranes. This allows for greater myosin and actin interaction and an increase in force production.Venoconstriction occurs as a response to sympathetic nervous system stimulation. Sympathetic stimulation constricts the veins that drain skeletal muscle. This causes greater blood to flow back to the heart.The muscle pump is the rhythmic contraction and relaxation of skeletal muscle that compresses the veins and thus drains the skeletal muscle. This causes greater blood flow back to the heart. The muscle pump is very important during both resting and exercise conditions. During exercise, the respiratory pump helps increase venous return. The pressure within the chest decreases and abdominal pressure increases with inhalation, thus facilitating blood flow back to the heart. Because of the increased respira tory rate and depth of breathing during exercise, this is an effective way to increase venous return. The circulatory system is a closed-loop system, and flow through the circulatory system is the result of pressure differences between the 2 ends of the system, the left ventricle (90 mm Hg) and the right atrium (approximately 0 mm Hg). Systemic blood flow affects hemodynamics. The control of blood flow during exercise is extremely important to ensure that blood and oxygen are transported to the tissues that need them most. Blood flow to tissues is dependent on the relationship between BP and the resistance provided by the blood vessels. Blood flow at rest is equal to the change in pressure divided by the resistance of the vessels (ie, BF = P/R, where BF is blood flow, P is pressure, and R is resistance). Blood flow during exercise is regulated by changing BP and altering the peripheral resistance of the vessels. The pressure change at rest in the cardiovascular system is 93 mm Hg, as follows: Mean aortic pressure = 93 mm Hg, mean right atrial pressure = 0 mm Hg, and driving pressure in the system = 93 mm Hg. During exercise, BP increases so that blood flow through the body increases. Blood flow is also increased during exercise by decreasing the resistance of the vessels in the systemic circulation of active skeletal muscle. Resistance is determined by the following formula: Resistance = (length of tube X viscosity of blood)/radius. Changing the radius of the vessels has the most profound effect on blood flow. Doubling the radius of a blood vessel decreases resistance by a factor of 16. Decreasing the radius of a blood vessel by half increases resistance by a factor of 16. The arterioles have the most control over blood flow in the systemic circulation. The changes in oxygen delivery to muscle during exercise are: BP increases as exercise intensity increases, rising from approximately 120 mm Hg to approximately 200 mm H, SV increases during exercise until 40% of VO2max (maximum oxygen uptake level) is reached, rising from approximately 80 mL/beat to approximat ely 120 mL/beat, HR increases with intensity until VO2max is reached,rising from approximately 70 beats per minute to approximately 200 beats per minute, Cardiac output increases with intensity until VO2max is reached, rising from approximately 5 L/min to approximately 25-30 L/min. The arterial-venous oxygen difference is the amount of oxygen extracted from the blood as it passes through the capillary bed. This difference rises from approximately 4 mL of oxygen per 100 mL of blood at rest to approximately 18 mL of oxygen per 100 mL of blood during high-intensity aerobic exercise.At rest, 15-20% of blood goes to skeletal muscle; during exercise, this amount increases to 80-85%. The percentage of blood to the brain decreases, but the absolute amount increases. The same percentage of blood goes to cardiac muscle, but the absolute amount increases. Blood flow to visceral tissues and inactive skeletal muscle reduces. In addition, the cutaneous blood flow initially decreases, but it later increases during the course of exercise.The redistribution of the blood is brought about by several mechanisms. During exercise, generalized vasodilatation occurs because of the accumulation of vasodilatory metabolites. This leads to a decrease in the peripheral resistance, which, in turn, elicits a strong increase in the sympathetic activity through the activation of baroreceptors. The increase in sympathetic activity leads to vasoconstriction in the visceral organs, whereas the vasodilatation predominates in the blood vessels of the muscles and the coronary circulation because of the local vasodilatory metabolites. The cutaneous blood vessels initially respond to the sympathetic activity by vasoconstriction. As the exercise continues, temperature reflexes are activated and cause cutaneous vasodilatation to dissipate the heat produced by the muscle activity, resulting in an increase in the cutaneous blood flow. The local blood flow is controlled by chemical factors, metabolites, paracrines, physical factors such as heat or cold, stretch effects on endothelial membrane, active hyperemia, and reactive hyperemia. The paracrine regulation is mainly regulated by nitric oxide, histamine release, and prostacyclin. Nitric oxide diffuses to smooth muscle and causes vasodilation by reducingcalcium entry into smooth muscle.HR and blood flow are controlled by various centers in the brain. These centers receive input from receptors located throughout the body. The centers work to initiate the appropriate response from tissues and organs in the body. Aerobic exercise requires oxygen to be present for the generation of energy from fuels such as glucose or glycogen. Aerobic exercise results in no buildup of lactic acid as a result of metabolism. This process is more efficient than anaerobic metabolism. During normal rest and aerobic exercise, carbohydrates and fats are used as fuels. A high degree of aero bic fitness requires a well-adapted ability to take in, carry, and use oxygen. Laboratory measurements are most accurate, but they are expensive. An individuals fitness level may be estimated according to these measurements. Anaerobic exercise produces lactic acid and is usually of short duration. Anaerobic exercise is high intensity and has a greater inherent risk of injury. Individuals who are unfit have a lower anaerobic threshold than athletes who are aerobically trained. The well-trained athlete may be able to approach 80% of the VO2max aerobically without lactate production. The usual VO2 measurements are in L/min; however, if the size of the individual needs to be accounted for, the measurements may be in mL/kg/min. The values for the average person aged 20 years are 37-48 mL/kg/min. Male athletes who are highly trained may approach measurements in the high 70s to low 80s. Training enhances the ability of the body, in particular the muscle cells, to better handle oxygen. Musc le must be able to use oxygen efficiently to keep anaerobic metabolism at a given level of effort to a minimum. Cardiac output is a major determinant of oxygen uptake. VO2max declines with age as the maximum HR declines. This is one of the major factors causing the approximately 7% decline with each decade of life after age 30 years. Muscle training and use of oxygen at the end organ, muscle, is the second factor that affects oxygen uptake. The arterial-venous oxygen difference comes about as a combination of arterial oxygen content, shunting of blood to muscles, and the muscle extraction of oxygen. Training results in a more efficient heart and an increase in the maximum SV. An increase in VO2 results in an ease in the stress of a given workload. When maximum SV is increased, the heart can work more efficiently at a given pulse rate. This lessens the necessity of an increased pulse at a given workload. Resting pulse is lower, as is the pulse at any given workload. One metabolic uni t (MET) equals the VO2 at rest. The estimate of the value of one MET is 3.5 mL of oxygen per kg/min. Conversion of VO2 measurements may be obtained by dividing the value of the VO2 in mL of oxygen per kg/min by the value of one MET or 3.5. For example, a VO2 measurement of 35 mL of oxygen per kg/min is equivalent to an output of 10 METs. Cardiovascular changes during isometric exercise differ from those during dynamic exercise. Static exercise causes compression of the blood vessels in the contracting muscles, leading to a reduction in the blood flow in them. Therefore, total peripheral resistance, which normally falls during dynamic exercise, does not fall and may, in fact, increase, especially if several large groups of muscles are involved in the exercise. The activation of the sympathetic system with exercise thus leads to an increase in HR, cardiac output, and BP. Because the total peripheral resistance does not decrease, the increase in HR and cardiac output is less and an increase in the systolic, diastolic, and mean arterial pressure is more compared with those seen with dynamic exercise. Because BP is a major determinant of afterload, the left ventricular wall stress, and thus the cardiac workload, is significantly higher during static exercise compared with the cardiac workload achieved during dynamic exer cise.In most cases, the SV plateaus at a VO2 of approximately 40-60% of the maximum. This applies to both trained and untrained males and females. The SV for untrained males may approach 100-120 mL/beat/min. For trained males, this value is 150-170 mL/beat/min. For highly trained athletes, maximal SV may reach or even exceed 200 mL/beat/min. The values for women are lower than those for men. Maximal SV for untrained women is usually between 80 mL/beat/min, and for trained women, itisusually between100 mL/beat/min. These changes translate into an increase in the circulation blood volume and in cardiac output, with a corresponding decrease in the resting HR and the resting and exercise BP. The heart undergoes certain morphologic changes in response to chronic exercise, commonly seen via echocardiography. These morphologic changes define what is commonly referred to as an athletic heart. Athletic heart syndrome is characterized by hypertrophy of the myocardium (ie, an increase in the m ass of the myocardium). Although the hypertrophy in athletes heart is morphologically similar to that seen in patients with hypertension, several important differences exist. In contrast to the hypertension-induced hypertrophy, the hypertrophy in the athletic heart is noted in absence of any diastolic dysfunction, with a normal isovolumetric relaxation time, with no decrease in the peak rate of left ventricular filling, and with no decrease in the peak rate of left ventricular cavity enlargement and wall thinning. Because the wall stress in the athletes heart is normal, sometimes the hypertrophy seems to be disproportionate to the level of resting BP. In addition, the rate of decline in the left ventricular hypertrophy and mass is much more rapid when the training is stopped compared with the regression in the same parameters in treated hypertension. On average, the decline in these parameters is seen 3 weeks after stopping exercise, and these morphologic changes can be seen on echo cardiograms. Sometimes, these morphologic changes are confused with the changes seen in patients with hypertrophic cardiomyopathy (HCM). A few important morphologic differences exist. In athletic heart syndrome, the hypertrophy is usually symmetrical, as opposed to the asymmetrical hypertrophy in HCM. Also, the left ventricular size isgenerally normal or increased, and the left atrial size is normal, as opposed to a small left ventricular cavity with a larger left atrial cavity size (usually 4.5 cm) in HCM. Despite these differences, sometimes making a distinction between 2 conditions is a challenge. Exercise is accomplished by alteration in the body response to the physical stress (exercise physiology). These responses to exercise include an increase in the HR, BP, SV, cardiac output, ventilation, and VO2. The metabolism at the cellular level is also modulated to accommodate the demands of exercise. These changes occur temporarily during the exercise. Long-term changes also occur in the body metabolism and function.

The Things They Carried By Tim O Brien - 917 Words

The Things They Carried is an autobiographical novel written by Tim O’Brien that details his time as a soldier in the Vietnam War. Considered to be â€Å"the best work of fiction ever written about Vietnam, some even think it is the best about war,† (Greenya 1). The stories that are contained within the novel talk about themes such as loss, burdens, and the horrifying truths of the Vietnam War, the first war to take place during a more ‘modern’ era, as the tragedies of the war could be broadcasted through television. Much like many soldiers that fought in the war, Tim O’Brien was forced to face through many tragedies. Due to this, the book is used to preserve those who have died in Tim O’Brien’s life. The two chapters within The Things They Carried develop the importance of O’Brien’s coping mechanism. In The Little Brown Reader, ‘Snapshot: Lost Lives of Women’ by Amy Tan contains a similar structure to the two chapters of O’Brien’s novel. I believe that Tim O’Brien’s The Things They Carried is similar to Amy Tan’s ‘Snapshot: Lost Lives of Women in the structure detailing the past and the idea of keeping people’s lives preserved through the art of storytelling, O’Brien’s last two chapters are essential in showing this similarity. People often carry mementos as a sense of comfort or in order to remind themselves of something in the past, in the case of the men of Alpha Company the things that they carry is a sense of who they are. Tim O’Brien starts the beginning of the novel withShow MoreRelatedThe Things They Carried By Tim O Brien892 Words   |  4 PagesThe Vietnam War was a long, exhausting, and traumatic experience for all of the soldiers and those who came with them. The Things They Carried, by Tim O Brien illustrates the different affects the war had on a variety of people: Jacqueline Navarra Rhoads, a former nurse during the Vietnam war, demonstrates these effects within her own memoir in the book, The Forgotten Veterans. Both sources exemplify many tribulations, while sharing a common thread of suffering from mental unpredictability. DesensitizationRead MoreThe Things They Carried By Tim O Brien1377 Words   |  6 Pageslove to have it as good as we do. Tim O’Brien’s The Thin gs They Carried discusses many veterans who experience the burden of shame and guilt daily due to their heroic actions taken during the Vietnam War. The book shows you how such a war can change a man before, during, and after it’s over.     Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   As I reflect on the many conflicts America has been a part of, none can compare to the tragedies that occurred in The Vietnam war. As told in The Things They Carried (O’Brien), characters such as NormanRead MoreThe Things They Carried By Tim O Brien1457 Words   |  6 Pagesthe theme pertains to everyone regardless of their background. It conveys the same ideas to people from all across our society. Lastly, a classic is timeless, which means it has transcended the time in which it was written. In Tim O’Brien’s novel, The Things They Carried, he offers a new, intriguing way to view war or just life in general and also meets all of the crucial requirements mentioned above to qualify it as a book of literary canon. Though this book is technically a war novel, many peopleRead MoreThe Things They Carried By Tim O Brien1242 Words   |  5 Pagesâ€Å"Tim O’Brien is obsessed with telling a true war story. O Brien s fiction about the Vietnam experience suggest, lies not in realistic depictions or definitive accounts. As O’Brien argues, absolute occurrence is irrelevant because a true war story does not depend upon that kind of truth. Mary Ann’s induction into genuine experience is clearly destructive as well as empowering† (p.12) Tim O’s text, The Things they Carried, details his uses of word choice to portray his tone and bias. Tim O’BrienRead MoreThe Things They Carried By Tim O Brien1169 Words   |  5 Pagesbut are set in the past and borrows things from that time period. A story that fits this genre of literature is The Things They Carried. The story is about Tim O Brien, a Vietnam veteran from the Unite States, who tells stories about what had happ ened when he and his team were stationed in Vietnam. He also talks about what he felt about the war when he was drafted and what he tried to do to avoid going to fight in Vietnam. The Things They Carried by Tim O Brien was precise with its portrayal of settingRead MoreThe Things They Carried By Tim O Brien1004 Words   |  5 Pages Tim O’Brien is a veteran from of the Vietnam War, and after coming home from his duty he decided to be a writer. His work â€Å"The Things They Carried† is about a group of soldiers that are fighting in the Vietnam War. The first part of the story talks mostly about physical items that each soldier carries, and also mentions the weight of the items as well. Though, there is one exception to the list of physical things. Lieutenant Cross is a character of the story, and Tim O’ Brien quickly states theRead MoreThe Things They Carried By Tim O Brien896 Words   |  4 PagesTrouble without a doubt is what First Lieutenant Jimmy Cross c arried around his shoulders because he was out in war, where mistakes happen. Lost and unknown of his surroundings he had to lead his men into safety, while destroying anything they found. First Lieutenant Jimmy Cross only holds onto one thing for hope and that is Martha, the woman who he hopes is a virgin to come back to. Tim O’ Brien introduces symbolism by adding a character that has a meaning of purity and a pebble, which symbolizesRead MoreThe Things They Carried By Tim O Brien Essay832 Words   |  4 PagesSummary: â€Å"By and large they carried these things inside, maintaining the masks of composure† (21). In Tim O’brien’s The Things They Carried, the American soldiers of the Vietnam War carry much more than the weight of their equipment, much more than souvenirs or good-luck charms or letters from home. They carried within themselves the intransitive burdens—of fear, of cowardice, of love, of loneliness, of anger, of confusion. Most of all, they carry the truth of what happened to them in the war—aRead MoreThe Things They Carried By Tim O Brien1369 Words   |  6 PagesMany authors use storytelling as a vehicle to convey the immortality of past selves and those who have passed to not only in their piece of literature but in their life as an author. In Tim O’Brien’s work of fiction The Things They Carried, through his final chapter â€Å"The Lives of the Dead,† O Brien conveys that writing is a matter of survival since, the powers of s torytelling can ensure the immortality of all those who were significant in his life. Through their immortality, O’Brien has the abilityRead MoreThe Things They Carried By Tim O Brien1407 Words   |  6 Pages       Our introduction stated that in â€Å"The Things They Carried,† author Tim O’Brien tells us not directly of the soldiers of Vietnam, or the situations they find themselves in, but about the things they carry on their shoulders and in their pockets. These â€Å"things† identify the characters and bring them to life.   I find that to be true as the author unfolds the stories about war and the uncommon things one carries in to war both inadvertently and on purpose.  Ã‚  Ã‚  As it was noted: Stories about war –

Analysis Paper. Wikipedia - 838 Words

Launched on 15 January 2001, Wikipedia is a free encyclopedia that uses the web platform for online users to access. Boasting with over 26 million pieces of writing in 285 languages, Wikipedia has transformed to be a giant in the field of search engines optimization technology. The open source concept that it rides have made it cheap to access and a better choice for many online users. This is especially among the users who find it cumbersome to follow prolonged registration processes to access information on the internet. Any search term queried on the Googleâ„ ¢ home page search engine will definitely give a hit from the Wikipedia site, and if not present, a prompt will request the user to create a page for such a term. In this way,†¦show more content†¦In this particular article, issues have been raised for peer review. To begin with, the article appears to lack information by a way of proper referencing from reliable sources. Secondly, it sets a bad precedence to talk of personality biographies to the living. It is to my view that any article and especially the ones found in the Wikipedia should not have a biased or libelous view on issues. To correct this misgiving, I suggest that a proper research be conducted in regards to Jackie Chan from renowned journalists, who may find it a pleasure to access and interview Jackie Chan himself. In this regard, my role would fit in well as a peer reviewer rather an author or illustrator. This is partially because I possess excellent skills on information searching, data analysis and attention to details and because it is highly unlikely for me to secure a face-to-face interview session with Jackie Chan. However, due to the amount of time needed in background research and analysis, I would only attempt to add â€Å"Off Camera† section that will be open for peer review and talk on the website. Wikipedia Sandbox is a platform in the Wikipedia site that offers an experimental practical approach to editi ng articles in the Wikipedia. It is clearly structured with, my only proposition; to be that the summary area should be highlighted in a different color. This canShow MoreRelatedA Stand Against Wikipedia Essay1208 Words   |  5 PagesAgainst Wikipedia As Wikipedia has become more and more popular with students, some professors have become increasingly concerned about the online, reader-produced encyclopedia. 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This source will be very valuable for my paper as it is written by an expert and provides a wide variety of information pertaining to the band. It will be a useful resource in the analysis of both their road to success and the individual album News of the World as well as the dynamics that went into their achievements. Brooks, Greg, and Gary Taylor. â€Å"Album DetailsRead MoreBus 591 Complete Week 5624 Words   |  3 PagesBUS 591 Complete Week 5 Purchase here http://chosecourses.com/ashfordbus591completeweek5 Product Description Week 5 ASHFORD BUS 591 Week 5 DQ 1 Liabilities and Financial Analysis Liabilities and Financial Analysis. Discuss current liabilities and long-term liabilities. What are the differences between the two? Illustrate your understanding of liabilities, making sure to identify major types of current liabilities. 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She also writes about some of the sites featuresRead MoreState Regulation On Uber And Cab Drivers Essay1322 Words   |  6 PagesIntroduction The history of regulation could be traced back to the ancient civilizations such as standardized weights and measures in ancient Rome, paper currency system in China, and others including Egyptian, Indian and Greek (Plagiarism, Wikipedia: The Free Encyclopedia). In the modern society, governments choose to intervene to correct market failure, to achieve an equitable distribution of income and wealth and to improve the performance of economy (Geoff, 2006), such as the debate on state

Dancing with the North Stars free essay sample

â€Å"Wait a second! Is that our number?† Jackson nodded and we high-fived each other. My first ballroom dance competition was the first time I realized that I was really as good as I said I was. I found out that the most important thing in dancing was to be confident, or act confident. Acting was crucial. It all started around 6 a.m. I didn’t go to school that day so I could prepare. The coach bus would leave the studio at 2 p.m. So I had several hours to pack. I wasn’t going to be competing that Friday afternoon, but I was still exited beyond belief. My mom braided my hair and we drove to the studio to catch the coach bus. I spent the whole ride listening to my iPod and going over the dance steps in my head. Thus, the ride dragged on for an hour and a half. Finally, we arrived at the Shakopee ballroom. It was a huge room that reminded me of a cave. The ceiling was covered with some sort of brown shag carpet. I assumed it was to keep the loud music from getting out. It actually looked like a cave, and had an intimidating quality to it. I watched the other dancers perform for several hours, then I finally picked up a program. It actually looked more like a notebook and had over twenty pages. The cover said â€Å"Star Of The North State Games, Dancesport Competition.† I quickly flipped through it and noticed that all the dances were separated into 2 minute segments called heats. Then I read something that kind of scared me. My partner, Jackson, and I would be competing in American style tango, which was something we had never learned. We found our teacher and pulled her aside. She gave us a quick lesson but I still didn’t feel prepared. My partner Jackson was shorter than me. What a big surprise! (sarcasm) He wasn’t shorter by much. He had close cropped hair that stuck straight up like the bristles of a brush. His competing clothes were for a funeral. They were all black and made the cavern like room seem ever more gloomy. On Saturday I woke up at 4 a.m. and my mom, who was a chaperone, began the slow and sometimes painful process of fixing my hair. This routine was fairly familiar. First my mom would push, pull and comb my hair into a bun, using bobby pins, combs and hairnets. Then she loads it down with hairspray and unbelievable amounts of gel. When that dries, it becomes as hard as a rock. The last step is to attach decorative fake flowers with even more bobby pins. Our first scheduled dance was in heat 33 at nine o’clock. By the time that rolled around, remarkably, I still wasn’t nervous at all. First it was east coast swing, then rumba. Unfortunately, those were the ones I despised the most. What a way to start! I thought miserably. We lined up at the gate with the other competitors, to enter the floor. The announcer began to speak. â€Å"Heat numbers 33 and 34, amateur American rumba and amateur new comers swing semi-finals. American rhythm division. Presenting couple 101, Eric Almeida and Robin Shaw, couple 124 Jackson Davidson and Kelly Howell†¦Ã¢â‚¬  and so on. As each dance couple walked onto the floor he said the names and numbers. The music started and we waited for the tempo to pick up speed. Then we were dancing our hearts out. My feet, clad in two and a half inch heels seemed to barely touch the floor they were moving so fast. I smiled at the audience and the judges. Despite all the times I mixed up, I was havin g fun. Afterwards, I decided that I had done horribly and nothing could change my mind about that fact. My friends insisted that I had done well. But I still hoped the judges hadn’t been watching too closely. We danced in many more heats for American rhythm including Cha cha, swing and rumba. That made it all the way to 9:22. I was exhausted and sat down with a bottle of water, reviewing all my mistakes in my mind. It’s a miracle I didn’t trip somebody I thought half heartedly grinning. My friend again insisted I had done great but I wasn’t so sure. I waited in agony until the awards ceremony at noon. All the dancers were asked to come out onto the dance floor. Why bother? I thought as I followed Jackson onto the floor anyway. We stayed in the back of the crowd. The announcer began to speak and the judges handed out medals one by one. It seemed like everyone had won something but us, I rolled my eyes in anticipation. Then he got to our division. I held my breath. â€Å"Heat number 33!† he boomed into the microphone. â€Å"In first place east coast swing we have couple 124!† All was silent for a moment. I let out a great whoosh of breath I had been holding. â€Å"Wait a second!† I said â€Å"Isn’t that our number?† Jackson nodded. We high-fived each other and made our way to the front to accept our totally awesome gold medals, and 50 dollar scholarships. Much to my surprise and delight, we had to stay up there for almost the whole ceremony because we just kept winning. We won first in swing twice, first in cha cha once, along with a 3rd and 5th. In rumba, we got first once and 5th three times. Looking at the program later I realized that all the times our place had fallen below 3rd, we had been against people two levels higher than us. The smooth dance portion of the competition was about begin. It was 2:00 p.m. and heat number 169 came up. We glided across the floor like a boat on a calm sea as we danced American waltz. We made our movement sharp in American tango, in foxtrot we stayed on our toes. By the time we were done dancing my shoes were biting into my heals and my feet hurt! A great dancer once said  ¦ Dancers are the only athletes who arent allowed to show how much it hurts. And boy was I living those words right now! The two and a half inch heels were a torture device. But through all the cortes and feather steps I survived. We made it to finals six times, half in the higher levels. And several more medals came our way for a grand total of five gold, six silver, and two bronze along with two fifty dollar scholarships and several certificates for 4th and 5th place. That was the day that my confidence in dancing soared to epic proportions and I realized that my dream of becoming a great dancer was close r than I thought.