Write about three things you are an authority on Essay

Write about three things you are an authority on - Essay Example It also teaches us to put our trust in Allah regarding our familial and community relationships so that we could live peacefully with everybody. As one who has been raised in a highly technological environment, I could also say that I am well versed with the internet. The internet is currently the most popular medium used by people around the world to communicate. Where there is a computer and internet connection, one can learn about a lot of things about people one never met or places he never visited. The internet is an awesome discovery that very important because aside from the information, it also provides easier communication through social networking sites such as twitter and facebook. Moreover, it provides people entertainment such as video games. I, for one, play a lot of video games because it releases stress. I enjoy playing with my friends because it is one form of communication for us and it also serves as a common ground for us which we use to create closer relationships. When one has a computer and internet connection, it is easy to find games online and enjoy one’s

My Personal Support Group (Cheerleading) :: essays research papers

My Personal Support Group Honors I am often sorry that my parents did not take it upon themselves to enroll me in any recreational activities in my preadolescent years. I believe that sports are an integral part of growing up. They provide an opportunity to meet and interact with peers. Numerous occasions I can recall feeling excluded from the group because of my lack of involvement. Although I have to admit, I am not a tough girl. Most likely I would not excel in any contact sport.   Ã‚  Ã‚  Ã‚  Ã‚  Cheerleading tryouts proved to be a revelation. I knew it was the activity for me. Although I was not confident in my coordination, I vowed that it would improve with practice. I had regularly admired those spirited girls, being that my sister had once traveled that path. I faithfully attended all high school games, not to watch the players, but the cheerleaders. I was convinced that this was my calling.   Ã‚  Ã‚  Ã‚  Ã‚  The week of tryouts was non-stop practice. I lived, ate, and breathed cheerleading. My mother began to worry that I would not have the energy by the end of the week to try out. When te big day finally arrived I was a tight ball of nerves. I could hardly contain myself. I was brimming with 100 watts of nervous energy. The kind that gives one piercing pains throughout their body at the least expected moments. Waiting for the results my anxiety turned into burning tears. When my name was announced as a member of the squad I thought I would burst.   Ã‚  Ã‚  Ã‚  Ã‚  My freshman year of cheering was exceptional. I became fast friends with my entire squad. For the most part, we got along great. I imagine that we had more fun than the players, or fans. Faster than expected our season came to an end. It was time for tryouts once again.   Ã‚  Ã‚  Ã‚  Ã‚  Now that I knew the ropes, I was praying this tryout would be a breeze. I could not have been farther from the truth. I faithfully practiced every evening until the eagerly anticipated day. The same nervous energy overwhelmed my body as I walked onto the floor that afternoon. It seemed that within a second, the tryout was completed. Once again, I was forced to calmly wait for the crucial results. Finally the outcome was announced. â€Å"Varsity- Kristin Callaway, Jill Jackson, Katie Manley†¦Ã¢â‚¬  I had made the Varsity squad as a sophomore.

Lonely Miss Brill the Eavesdropper

Miss Brill by Katherine Mansfield is about a middle-aged English teacher who secretly listens to other people's conversation due to her loneliness. Every weekend Miss Brill goes out to the parade in a park and listens to other people's conversation because she has nobody to talk to but her fur coat. She treasures her fur coat as if it's her pet and has conversations with it. Towards the end of the story, she realizes that nobody likes her, therefore she goes home into her dark room and cries.Katherine Mansfield, uses imagery, characterization, and point-of-view uses these three literary elements to inform the meaning of the lonliness. The author uses imagery for the reader to better understand the story and to create the apperance of her loneliness. In the beginning of the story, the author states â€Å"She had taken it out of its box that afternoon, shaken out the moth powder†¦ rubbed the life back into the dim little eyes. † (Mansfield 1)Here, Miss Brill takes out her f ur coat and starts to talk to it and pets it as if it is her pet.From this, the reader can can visually interpret that Miss Brill had no friends or family to talk to when she was lonley. Furthermore, towards the end of the story, a girl at the park says, â€Å"It's exactly like a fried whiting. â€Å"(Mansfield 4) The reader can visualize the story the author intended on how the little girl at the park makes fun of Miss Brill of her fur coat saying that it looks like fried fish. After hearing this, Miss Brill goes home and cries in her dark room. In addition, the author uses point-of-view for the reader to step into the main characters' shoes.In the beginning of the story, when Miss Brill went to the park to watch the parade, the author states â€Å"Wasn't the conductor wearing a new coat, too? She sure it was new. † (Mansfield 1) From this quote, the reader can see that she went to the parade often, enough to know what the bandsmen wore each weekend to perform. Furthermore , the author states â€Å"But to-day she passed the baker's by, climbed the stairs, went into the little dark room- her room like a cupboard†¦ She sat there for a long time.† (Mansfield 4)After coming back from the parade, getting made fun of, she goes to her room in a depressed mood and cries by herself. Lastly, from the begininng of the story, the reader can tell that Miss Brill had a unique personality. From talking and petting her fur coat, to eavesdropping, her character is a bit different from others. Her lonliness could have lead her to eavesdrop on people and have a fur coat as her friend. The author states, â€Å"This was disappointing, for Miss Brill always looked foward to the conversation.† (Mansfield 1), to show her lonliness.In this quote, the reader can see that Miss Brill liked to talk to people and even if she wasn't in the conversation, she would like to listen to them. Furthermore, he author states â€Å"How she enjoyed it! How she loved sittin g there, watching it all! It was like a play. † (Mansfield 3) This quote is explaining how she enjoyed the parade as if it was a play. The reader can see that she entertained herself by going to the park every weekend to forget about her loneliness.The author successfully used these three literary elements for the readers to better understand the story, to create the appearance of her lonliness and visualize interpret what the author was intending to say. Authors using literary elements in their story is important because they can send what they're trying to say to the readers easily with the literary elements. Furthermore, it is important to the readers because the reader's can better understand the story and relate the story to the world. Reading this story, readers can understand people who too are lonely and step into their shoes to understand their feelings.

Filipino Language and Green Card Bearer - 3250 Words

Group 1 (Cheng, Uy, Alipio) Short Story: Wedding Dance Poem: Bonsai Group 2 (Rosabal, Gocela, Gamalinda) Short Story: The White Horse of Alih Poem: Patalim Group 3 (Barlin and Castillejo) Short Story: Mayday Eve Poem: Bihirang Masulat ang Kaligayahan Group 4 (De Jesus, Dela Cruz, Sioco) Short Story : My Brother’s Peculiar Chicken Poem: Poem 10 Group 5 (Chen, Uy, Qiu) Short Story: Dead Stars Poem: Gabu Group 6 (Fule, Lim, Quinzon) Short Story: The Small Key Poem: You Can Choose Your Afterlife Group 7 (Jeanjaquet, Quiogue, Manzo) Short Story: Ghost Poem: Si Lola Isyang at ang Matandang Puna ng Kaimito Group 8 (Tumulak, Brucelas, Casas) Short Story: Rice Poem: What Poetry Does Not Say Group 9 (Lopez, Gonzales, Lunaria)†¦show more content†¦( Direct and |more common representation like a rose, a heart, or a kiss? | |Indirect ) |Explain the line, â€Å"Araw-araw sinusubok naming mag-asawa ang talim n | |Describe Alih’s relationship with his brother. Omar. |gaming balaraw.† | |Explain the title. What is the significance/ symbolism of the white |Relate this with the last line, â€Å"Ganito kami lagi sapagkat labis ang | |horse in Alih’s life? |pag-ibig naming sa isa’t-isa.† | |What is the original plan of Omar and Alih for the 4th of July |Do you believe that true love is cut to the measure of great | |American parade? What are reasons behind it? |conflicts? Substantiate your answer. | |Explain the line: â€Å"Alih, simply, did not love his white horse, as he | | |did his bouri | | |GROUP 3 |Show MoreRelatedAmerican Holidays11778 Words   |  48 PagesSquare in New York City at 12 o’clock. This event can be seen all over the world on television. Valentine’s Day Saint Valentine’s Day is a day that is set aside to promote the idea of â€Å"love†. It is celebrated on February 14th. People send greeting cards or gifts to loved one and friends to shoe them that they care. Easter Easter is a major Christian holiday that commemorates the resurrection of Jesus Christ. It is celebrated on Sunday between March 22 and April 25. The 40 days leading up to EasterRead MoreOne Significant Change That Has Occurred in the World Between 1900 and 2005. Explain the Impact This Change Has Made on Our Lives and Why It Is an Important Change.163893 Words   |  656 Pagesup to 20 percent of the migrants to North America and Europe since the 1960s, as well as significant streams of professionals from the developed countries into the oil kingdoms. Several immigrant groups in the United States, from Indians and Filipinos to Argentines and Nigerians, have higher educational levels and family incomes than the native-born white population. Immigration law preferences for the wealthy and educated play an important role in this stream, as does the lack of intellectually

Risk Management A Global Supply Chain - 1796 Words

Research Paper: Risk Management in a Global Supply Chain Week 7 Research Paper/TLMT441 D001 Sum 14 Jerry King/Student ID: 4074738 Professor Little Abstract Risk management is a critical component to the success of any supply chain, yet this is still an area that sees little forward movement. In many organizations, risk management is viewed more as a reactive department, only becoming operational when a significant disruption arises in contrast to being an active and continual department with focused effort. As a supply chain moves to take on a global stance, risk management cannot be treated as a reactive measure. Global supply chains are exposed to greater risk than local/domestic supply chains as their linkage is more†¦show more content†¦By reviewing potential community solutions to risk management, supply chain managers will be better postured to develop an effective risk management solution for their organization. Risk management is a continual process that is used by every person throughout their day. It is an autonomous activity, that when an individual is presented with a situation their brain assesses the associated risk and quickly makes a determination as to whether that risk is acceptable; based on the potential benefit or the possibility of an adverse outcome. For just one person, this can be a difficult process and without preparation, the outcome is reliant on chance, as in a toss of a coin. This describes a basic reactionary process; the goal is to develop a proactive stance that eliminates, mitigates, or defers the effects of unknown and unexpected disruption events. Today’s global supply chain has been shaped by the past decades of focus and strategies based on achieving the lowest operational costs coupled with a push towards market expansion and supplier outsourcing. The expansion of global supply chains combined with the increasing number of joined connections to ext ernal business partners has significantly raised the possibility for supply chain disruptions (Poirier, Quinn, Swink, 2010). In today’s global business environment, the importance of risk management continues to grow daily. Several factors must exist up front to

Capital Reconstruction - 6150 Words

Capital Reconstruction Introduction:- The act of placing a company into voluntary liquidation and then selling its assets to another company with the same name and same stockholders, but with a larger capital base. It is the complete overhaul of the capital of a distressed company to save it from liquidation. The object of it is to enable the company to continue as a going concern by the removal of the burden of immediate debt, the attraction of additional capital and the creation of a viable financial structure. Definition:- The reconstruction of capital, which is also known as capital reconstruction, is defined as the plans made by a company for the restructuring of its capital base. Capital reconstruction involves major alterations†¦show more content†¦debt holders). Reconstruction Schemes This addresses the 2nd and 3rd points above. This involves the company * Writing off overdue debt interest and restructuring debt to have lower interest and extended maturity * Writing off cumulative preference shares dividend owed * Writing off amounts owed to suppliers * Issuing new shares (crediting equity reserves) to the previous debt holders, preference shares holders, suppliers for accepting to restructure the debts. Essentially debt holders convert to being equity holders, possibly retaining a lower debt amount. This allows them to recover their funds through the company’s recovery, as opposed to not recovering their funds when the company collapses. Liquidation via a New Company This involves: * Selling assets to another company * Using the proceeds to pay down remaining debts, and liquidating the business. * Profit recognized is based on proceeds less carrying costs of remaining net assets. * The buyer of the assets will still recognize Goodwill based on the fair value of the assets bought. Any of a range of financing transactions aimed at significantly altering the shape of a firms liabilities (cf. recapitalization; reconstructing). There are three basic ways in which this can happen: increases/decreasesShow MoreRelatedThe Demystification of the Freedmens Bureau Essay1262 Words   |  6 PagesThe role of the Freedmen Bureau in African-American development during the Reconstruction era has been a polarizing topic since the Bureau’s inception. While most concur that the Bureau was well intended, some scholars, believe that the Freedmen’s Bureau was detrimental to African-American development. One such scholar was W.E.B. Dubois, who in his book The Souls of Black Folk, expressed his discontent with the actions of the Bureau and suggested that the Bureau did more harm than good. 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Exercise Physiology Free Essays

Direct calorimetry uses the measurement of heat production as an indication of metabolic rate. * Indirect calorimetry estimates metabolic rate via the measurement of oxygen consumption. * Energy expenditure can be expressed in L†¢min-1, kcal†¢min-1, ml†¢kg-1†¢min-1, METs, and kcal†¢kg-1†¢hr-1. We will write a custom essay sample on Exercise Physiology or any similar topic only for you Order Now * To convert L†¢min-1 to kcal†¢min-1, multiply by 5. 0 kcal†¢L-1. * To convert L†¢min-1 to ml†¢kg-1†¢min-1, multiply by 1000 and divide by body weight in kilograms. * To convert ml†¢kg-1†¢min-1 to METs or kcal†¢kg-1†¢hr-1, divide by 3. 5 ml†¢kg-1†¢min-1. Efficiency: * Exercise work rate Efficiency decreases as work rate increases * Speed of movement * There is an optimum speed of movement and any deviation reduces efficiency * Muscle fiber type * Higher efficiency in muscles with greater percentage of slow fibers SUMMARY: Net efficiency is defined as the mathematical ratio of work performed divided by the energy expenditure above rest, and is expressed as a percentage. * The efficiency of exercise decreases as the exercise work rate increases. This occurs because the relationship between work rate and energy expenditure is curvilinear. To achieve maximal efficiency at any work rate, there is an optimal speed of movement. * Exercise efficiency is greater in subjects who possess a high percentage of slow muscle fibers compared to subjects with a high percentage of fast fibers. This is occurs because slow muscle fibers are more efficient than fast fibers. * Not possible to calculate net efficiency of horizontal running * Running Economy * Oxygen cost of running at given speed * Lower VO2 (ml†¢kg–1†¢min–1) at same speed indicates better running economy * Gender difference * No difference at slow speeds At â€Å"race pace† speeds, males may be more economical that females 170-188 CIRCULATORY RESPONSE TO EXERCISE Organization: arteries branch to form vessels, vessels become microscopic and form arterioles, which develop into â€Å"beds† called capillaries. Capillaries are the smallest and most numerous of blood vessels—exchange of oxygen, CO2, and nutrients. Blood passes from capillary beds to venules that move back to heart and increase in size becoming veins. Mixed venous blood= mixture of venous blood from both upper and lower body in the right side of the heart. *it represents an average of venous blood from ent ire body. HEART: Right/left side separated by muscular wall called interventricular septum (prevents mixing blood from sides). Valves: Bicuspid/mitral = left atrioventricular valve **atrioventriculars close when heart contracts to prevent backflow. Tricuspid= right atrioventricular valve Semilunar valve (pulmonary semilunar)- b/w right ventricle and pulmonary artery. Prevents backflow from arteries into ventricles. Aortic valve (aortic semilunar)= b/w left ventricle and aorta. Also prevents backflow†¦ Right side pumps deoxygenated blood to pulmonary circuit so oxygen can be loaded and CO2 released. Left side pumps oxygenated blood to body via systemic circuit. RIGHT: to lungs LEFT: to body Heart sounds are due to closing of atrioventricular valves (first sound-systole) and the closing of aortic and pulmonary valves (second sound-diastole) Wall of heart is 3 layered: 1) outer layer is epicardium, 2) muscular middle layer called myocardium, 3) inner layer endocardium. Myocardium contracts to force blood out. Right and left coronary arteries supply myocardium Cardiac muscle fibers are shorter than skeletal and are branched and involuntary. Heart muscle fibers are all connected via intercalated discs- transmit electrical impulses. They are leaky membranes that allow ions to cross b/w fibers (contract together= functional syncytium). *atria contract separate from ventricles because there is a separating layer of CT *heart is only type 1, slow fiber- highly aerobic, many mitochondria (more than skeletal). Cardiac cycle: Systole- contraction phase (blood ejected) Diastole- relaxation period (arterial BP decreases– filling) There is also an atrial systole and diastole. Atrial contraction during ventricular diastole, atrial relaxation when ventricular systole. *SO there are TWO steps of heart pumping. *atria contract together, which empties arterial blood into ventricles. . 1 second and then ventricles contract to deliver blood to systemic and pulmonary circuits. *when atria relax, blood flows into them from venous circulation as they fill, pressure inside increases. Increase in HR less time spent in diastole (not as much impact on time in systole until at high HR) Arterial Blood Pressure: -greatest in arteries BP = the force exerted by blood against the arterial walls. Determined by how much blood is pumped and the resistance to blood flow. -male: 120/80, female: 110/70 systolic/diastolic dif between the two is calls â€Å"pulse pressure† â€Å"mean arterial pressure†= av pressure during cardiac cycle. determines rate of blood flow through systemic circuit Mean arterial pressure = DBP + . 33 (pulse pressure) (DBP: diastolic blood pressure) (pulse pressure: dif between systolic and diastolic pressure) SO, if someone has bp 120/80, Mean arterial pressure= 80mmHg + . 33(120 – 80) = 93 mmHg *but this calculation is only used for cardiac cycle at rest. Hypertension- increases workload on left ventricle so cardiac mass increases, but this eventually results in diminished pumping capacity. Also increase risk for other disease/damage of body parts like brain and kidneys. 20% all US adults Factors influencing arterial BP: ) cardiac output—amount of blood pumped from heart 2) total vascular resistance – sum of resistance to blood flow by all systemic blood vessels. —blood volume, blood viscosity Mean arterial blood pressure = (cardiac output x total vascular resistance) *so increase in either will increase the mean art. BP Blood pressure increases when increase in: blood volume, HR, SV, blood viscosity, peripheral resistance. And it decreases when any of those decrease. BP regulated short term by the sympathetic NS, long term by the kidneys (bc they control blood volume). Baroreceptors- sense arterial blood pressure in carotid artery and aorta. Increase in pressure send impulses to CV control center which will decrease the sympathetic activity (lowers cardiac output and/or reduces vascular resistance lowers BP). Decrease in BP reduction of baroreceptors activity to brain CV control center increases sympathetic activity raise BP to normal Electrical Activity of the Heart: Sionatrial node (SA node)- in the right atrium (by the vena cava). responsible for spontaneous electrical activity in normal heart, it’s the pacemaker. Occurs due to decay of resting membrane potential (bc of diffusion of NA during diastole). When SA is depolarized and reaches threshold, a wave of depolarization is spread over the atria contraction! Wave of atrial depolarization needs special conductive tissue to transport it to the ventricles. This conductive tissue is called the atrioventricular node (AV node- in floor of right atrium). When blood from atria empties into ventricles, the conductive pathways branch into smaller fibers called purkinje fibers that spread the wave of depolarization through ventricle so it can contract. Electrocardiogram (ECG)- recording of electrical charges in myocardium during cardiac cycle. –ability of hear to conduct impulses. P wave- depolarization of atria QRS complex- depolarization of ventricles and atrial repolarization(during beginning of systole, aprx . 10 seconds after Pwave) T wave- ventricular repolarization (same time as QRS, but at the beginning of diastole) CARDIAC OUTPUT (Q): Q = HR X SV Regulation of heart rate: -because SA node controls HR, changes in HR involve factors influencing SA node. Most influence over HR: parasympathetic and sympathetic NS Parasympathetic NS- acts as braking system to slow HR using vagus nerve which touches SA and AV node and releases acetylcholine decrease activity of SA and AV nodes due to hyperpolarization= reduce HR. —initial increase in HR during exrcise up to 100bpm is due to decrease in parasympathetic tone. Sympathetic fibers use cardiac accelerator nerves to innervate both SA node and ventricles. Increase HR and myocardial contraction when they release norepinephrine. –beta receptors *all beta-blocking drugs will decrease resting HR and exercise HR. CV control center regulates- pressure receptors in right atrial respond when there is increased pressure by increasing Q to reduce the BP. Body Temp also influences HR. increase temp = increase HR Regulation of stroke volume: ) end-diastolic volume (EDV aka â€Å"preload†) (volume of blood at end of diastole) 2) average aortic BP 3) strength of ventricular contraction EDV- Frank and Starling, stronger contraction with higher EDV bc there is more stretch of ventricles. EDV influenced by rate of venous return to heart- more return= higher EDV. Venous return regulated by: 1) venoconstriction – reduced volume capacity of veins to store blood. *sympathetic control- activates organ increase HR (the parasympathetic inhibits activation decrease HR) 2) muscle pump—muscles contract and compress veins blood pushed to heart. Venous return reduced when muscles are contracted. isometric exercise, mechanical. 3) respiratory pump- breathing decreases pressure in chest and increases abdominal pressure so venous blood flows from abdominal into thorax and increases return. *more respiration in exercise Aortic pressure (mean arterial pressure/afterload)- to eject blood, pressure in left ventricle must be more than in the aorta. Increase in aortic pressure= decrease SV. Less afterload during exercise bc arteriole dilation reduces afterload. Circulating epinephrine-norepinephrine (increase Ca+ entry) and direct sympathetic stimulation of heart by cardiac accelerator nerves. Increase in sympathetic stimulation of heart increases SV at any level of EDV. HEMODYNAMICS: -blood flow is in a continuous loop. Physical characteristic of blood- composed of plasma (watery portion, contains ions/proteins/hormones) and cells (called the hematocrit: RBC/platelets/WBC). Hematocrit= 42% of blood (38% in college women), the rest is plasma. RBCs are largest part of a blood cell—influence viscosity. Anemia decreases RBC, so decreases viscosity Relationships among pressure, resistance, and flow: Rate of flow is proportional to pressure difference. Inversely proportioned to resistance. Blood Flow= change in pressure/ resistance -Change in pressure is the dif between the two ends of the circulatory system -resistance due to length of vessel and viscosity, and radius of vessel **Blood flow increases with increase in BP or with decrease in resistance. -during exercise blood flow increases mainly due to decrease in resistance with small rise in pressure. Resistance = (length x viscosity)/ radius^4 (**so radius is VERY important-vasoconstriction/vasodilation) Sources of vascular resistance: -vasoconstriction/vasodilation the greatest vascular resistance in blood flow occurs in arterioles. Pg 188 – 196 Changes in oxygen delivery to muscle during exercise: Metabolic need for O2 increases so there is an increase in blood flow to muscle- increase O2 delivery by 1) increased cardiac output and 2) redistribution of blood flow from inactive organs to working skeletal muscle. Changes in cardiac output during exercise: -cardiac output increases in proportion to metabolic rate for task -maximal cardiac output decreases after 30 yrs of age mostly bc of decreased maximal heart rate with age. Cardiac output = heart rate X stroke volume Max HR = 220 – age (years) Changes in Arterial-Mixed Venous O2 content during exercise: -change in arterial-mixed venous oxygen difference (a – VO2 diff)during exercise. It represents the amount of O2 taken from 100 ml of blood by the tissue during 1 systemic circuit. The relationship between cardiac output (Q), a – VO2 diff, and oxygen uptake is given by the Fick equation: VO2 = Q X (a- VO2 diff). Fick equation: VO2 is equal to the product of cardiac output and the a-VO2 diff. *SO INCREASE IN CARDIAC OUTPUT OR (a – VO2 diff ) WOULD ELEVATE VO2. Redistribution of Blood Flow During Exercise: Increase flow to skeletal muscles and decrease to less-active organs like liver, kidneys, GI tract. Increase in muscle blood flow and decrease in splanchnic blood flow change as a linear function of %VO2 max. -at rest aprx 15-20% total cardiac output is directed to skeletal muscles. -during maximal exercise 80-85% of total cardiac output goes to skeletal muscle (to help meet oxygen needs for contracting) -during heavy exercise % that goes to brain is reduced compared to rest. -total coronary blood flow increases due to increase in cardiac output -reduction of blood flow to skin and abdominal organs Regulation of local blood flow during exercise: Regulated with arterioles in skeletal muscles that have a high vascular resistance at rest (due to adrenergic sympathetic stimulation which causes vasoconstriction). This results in low blood flow to muscle (4-5 ml/min per 100g muscle) but this is still 20-25% total flow from heart. **autoregulation (an intrinsic metabolic control) -vasodilation (opens vessels) results from local changes during exercise like decrease in O2 tension, increase in CO2 tension, nitric oxide, potassium and adenosine concentrations, increase in acidity. Vasodilation reduces vascular resistance and therefore increases blood flow. Also aided by recruitment of cappilaries- at rest only 5-10% of capillaries are open, all are open during heavy exercise. **level of vasodilation regulated by metabolic need of the muscle (intensity and # of motor units recruited determines blood flow to active muscle fibers) during exercise, vascular resistance in skeletal muscle decreases and vascular resistance to flow in the visceral organs/other inactive tissue increases. *because on increased sympathetic output to these organs regulated by CV control center. increase in visceral vasoconstriction during exercise decreases blood flow to viscera by 20-30% resting value. During exercise in upright position, SV reaches plateau at 40% VO2 max, therefore, at work rate about 40% VO2 max, the rise in cardiac output (Q) is due to increased HR only. CIRCULATORY RESPONSES TO EXERCISE: HR and blood pressure at any VO2 (oxygen uptake) are higher in arm than in leg -higher HR in hot/humid conditions emotional influence- HR increase with high emotion because increase in sympathetic NS activity. Does not generally alter peak HR or blood pressure during exercise itself but does elevate pre-exercise HR. ransition from rest to exercise- increase in HR and SV and cardiac output at beginning of exercise (after 1st second! ) then if work is constant it plateaus recovery from exercise- recovery from short-term/low intensity is rapid. Recovery after exercise better in trained individuals bc their HR doesn’t get as high. Recovery from long-term is slower because elevated body temp. incremental exercise- HR and cardiac output increase in direct proportion to O2 uptake. More O2 uptake = more blood flow to muscles. Plateau of cardiac output and HR at 100% VO2 max (no more hemoglobin to transport O2). The increase in HR and systolic BP results in increased workload on the heart (increased metabolic demand on heart estimated by: double product = HR x systolic BP) maximal exercise increases workload on heart by 500% Useful equation to tell patients with coronary artery blockage how they can exercise. **cardiac output increases because decrease in vascular resistance to flow and increase in mean arterial blood pressure. Arm vs. Leg exercise- HR and BP higher in arm because greater sympathetic outflow to heart during arm work when compared to leg work. Large increase in BP for arms because of vasoconstriction in inactive muscle groups. Large muscles (legs) have more resistance vessels dialated, so there is lower peripheral resistance and lower BP (cardiac output x resistance= pressure). Intermittent exercise- (interval training), recovery of HR and BP depends on level of fitness, environmental conditions, and duration and intensity. Recovery not complete if the temperature is high because that increases HR. with repeated bouts of light exercise, many repetitions can be preformed. Prolonged exercise- cardiac output at constant level. SV declines while HR increases because the increase (cardiac output constant bc HR increases and balances SV decrease). Cardiovascular drift= increase in HR and decrease in SV during prolonged exercise. , it is due to rising body temp and reduction in plasma volume. Reduction in plasma volume reduces venous return to heart and thus decrease in SV REGULATION OF CARDIOVASCULAR ADJUSTMENTS TO EXERCISE –increase in sympathetic stimulation of heart and vasodilation of arterioles and increase resistance of vessels in less-active areas= increase cardiac output so that blood flow to muscle matches metabolic needs. Central command- CV change due to centrally generated cv motor signals **also modified by heart mechanoreceptors, muscle chemoreceptors, muscle mechanoreceptors, and pressure-sensitive receptors (baroreceptors) â€Å"tuners† during exercise: muscle chemoreceptors- muscle metabolites (K, lactic acid, etc. ) muscle mechanoreceptors- force and speed of muscular movement baroreceptors- change in arterial BP- regulate arterial BP Page 267-269, 277-280 VO2 max = HR max X SV max X (a- vO2 dif)max STROKE VOLUME SV = End diastolic volume(EDV) – End systolic volume (ESV) *EDV increase ecause increase in ventricle size/increase in venous return (â€Å"preload†), increase in myocardial contractility, and decrease in resistance to blood flow out of heart (â€Å"afterload†) End diastolic volume (EDV) Left ventricle increase with endurance training bc of volume loading during exercise Plasma volume increases with endurance training (loss of plasma volume = decrease VO2 m ax in first weeks of detraining) **EDV increase with training. FRANK-STARLING MECHANISM: increase stretch of ventricle = increased SV Cardiac contractility- strength of contraction when fiber length, afterload, and HR are constant. Afterload- peripheral resistance against which the ventricle contracts in order to push portion of EDV into aorta. Decrease in resistance = increase max cardiac output, SO arterial BP is unchanged (MAP = Q x TPR) **endurance training lower resistance in working muscle to facilitate higher blood flow blood pressure falls when muscles capacity for blood flow exceeds hearts ability to provide it.. —to maintain BP some of muscle mass is vasoconstricted (other is vasodialated) training decrease resistance of vascular bed to match increase in max cardiac output to maintain BP Arteriovenous O2 difference: increase in difference could be due to elevation of the arterial oxygen content, or decrease in the mixed venous oxygen content. -increase capacity of muscle to extract O2 after training probably because increase in capillary density (mitochondria too) accommodate more blood flow *training-induced increase in maximal SV due to increase in preload and a decrease in afterload. Preload increased because end diastolic ventricular volume and associated increase in plasma volume. Afterload decreased because decrease in arteriolar constriction in trained muscles increases maximal muscle blood flow but no change in mean arterial BP. in young, sedentary ppl, 50% of increase in VO2 is bc of increase in systemic a-VO2 dif (due to increase in capillary density). Decrease in VO2 max when you stop training because decrease in max SV and decrease in oxygen extraction. 277-280 net cost of walking is ? of net cost running use pace maker test for kids field test for CRF use walking, running, stepping. Can test many ppl at low cost. Hard to measure response for some, and motivation can be a variable. VO2 max estimates from all-out run tests are based on the linear relationship b/w running speed and oxygen cost of running. VO2 max estimated in endurance test is influences by CV function and % body fat. Canadian home fitness test: submaximal, uses lowest two 8-inch steps in a staircase. Evaluates cardiorespiratory fitness using post-exercise HR. 1 mile walk test: VO2 based on age, weight, sex, time, HR improved fitness: lower HR and/or time and higher VO2 max cardiorespiratory fitness measured using: treadmill, cycle ergometer, stepping bench measured by: palpation (carotid/radial artery), stethoscope (systolic- 1st korotkoff sound, diastolic- 4th sound), ECG ncreased metabolic demand on heart estimated by: double product= HR x systolic BP -double product is estimate of myocardia O2 demand arrhythmia- irregularity in normal electrical rhythm: atrial fibrillation, premature contractions conduction disturbances- depolarization is slowed/blocked (first-degree AV block or bundle branch block) myocardial ischemia- inadequate perfusion of the myocardiumflow limitation= O2 insufficiency (angina pectoris- sympt om)(ST segment depression-sign upsloping, horizontal, downsloping—downsloping is worst) teady state: HR measured over 15-30 seconds post exercise HR: measured for 10 seconds within first 15 seconds of stopping exercise, then multiple the # by 6 HR and systolic BP increase with exercise intensity * Typical measurements obtained during a graded exercise test include heart rate, blood pressure, ECG, and rating of perceived exertion. * Specific signs (e. g. , fall in systolic pressure with an increase in work rate) and symptoms (e. g. , dizziness) are used to stop GXT. VO2 max: â€Å"gold standard† to measure CRF VO2 increases with increasing loads on a GXT until max capacity reached- VO2 estimated based on final work rate achieved in graded exercise test- can also be estimated from HR responses to submaximal exercise using age, also consider environmental factors. Estimation of VO2 max from last work rate: Poorly fit individuals take longer to achieve the steady state at moderate/heavy work rates may overestimate the VO2 max when using formula Estimation of VO2 max from submaximal HR response: HR plotted against work rate (or estimated VO2) until termination criterion of 70%- 85% of age-adjusted maximal HR reached (220-age). careful of environmental factors- dehydration, temp, emotions, medication * VO2 max Estimation of VO2 max from Last Work Rate Estimation of VO2 max from Submaximal HR Response CRITERIA FOR ACHIEVING VO2 MAX: * Leveling off of VO2 with higher work rate lt;150 ml†¢min–1 or lt;2. 1 ml†¢kg–1†¢min–1 * Post-exercise blood lactate gt;8 mmoles†¢L–1 * R gt;1. 15 * HR within 10 beats†¢min–1 of age-predicted maximal HR * Usefulness has been questioned * Should not expect subjects to meet all criteria * Graded Exercise Test: Protocols Treadmill Cycle Ergometer Step Test * Gra ded Exercise Tests: Measurements Heart Rate Blood Pressure ECG Rating of Perceived Exertion Termination Criteria Treadmill- don’t have to adjust for body weight in calculation because subject is carrying their own weight ( so VO2 is proportional to weight). Health or cardiac risk inventory—PAR-Q (physical activity readiness questionnaire) – heart condition, pain in chest when doing physical activity, lose balance/dizziness/lose consciousness, bone/joint probs, drugs/meds for BP or heart condition * Estimating VO2 max * Based on extrapolating submaximal HR during incremental test * YMCA protocol How to cite Exercise Physiology, Papers