KIN 3431 LAB 10 post lab Cardiovascular Response to Exercise PDF

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Lab Report Cardiovascular Response to Exercise...

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KIN 3431 – Exercise Physiology Laboratory Lab Report Topic:

Introduction During this lab we discussed the cardiovascular response to exercise. The functions of the cardiovascular system are to transport O2 and nutrients to tissue cells, remove metabolic waste, and regulate body temperature. During exercise the body demands a higher amount of O2 due to the increased load. This is met by increased cardiac output and redistribution of blood flow. I am a firm believer that exercise training protects the heart. Regular exercise is cardio protective; it reduces the likelihood and amount of myocardial damage from heart attack. Blood pressure is the force exerted by blood against the arterial walls and is determined by how much blood is pumped and the resistance to blood flow. A sphygmomanometer can be used to measure arterial blood pressure. Systolic blood pressure is the pressure generated as blood is ejected from the heart during ventricular contractions. Diastolic blood pressure occurs during the diastole of the ventricles when the arterial blood pressure decreases. The pulse pressure is the difference between the systolic and diastolic blood pressure. The increased demand for O2 placed on the heart during physical activity can be estimated by examining the rate pressure product. The rate pressure product (RPP) = HR x SBP. Factors affecting arterial blood pressure are cardiac output and total vascular resistance. Mean arterial blood pressure = Cardiac output x total vascular resistance. Several physiological factors that increase blood pressure are increases in: blood volume, heart rate, stroke volume, blood viscosity, and peripheral resistance. Rating of perceived exertion is the rating scale used to identify the level of difficulty that an individual perceives he/she is experiencing. Borg’s RPE is the original scale which begins at 6 to 20 to approximate the HR values from rest to maximum. Normal BP is 120/80 mm HG and normal HR is 60 BPM. I expect blood pressure, heart rate, and any products that derived from blood pressure & heart rate to increase as exercise is conducted to meet the demands of the bodies increased requirement of O2. Methods We were divided into groups of three of three. One subject conducted the cycling exercise of incremental load while the other two group members measured the subjects HR and BP. We utilized a sphygmomanometer to measure arterial blood pressure which consists of an inflatable arm cuff connected to a column of Hg. Biological data was taken of the subject conducting the exercise such as age, sex, height, and mass. HR, BP, RPP, and RPE of the subject conducting the exercise were measured at different phases during this experiment. Each phase lasted for 5 minutes. The phases in chronological order: Seated Rest, warm up 25 watt, stage one 75 watt, stage two 125 watt, cool down 25 watt, seated rest.

Results Subject: Jun - Age: 25 | Sex: Male | Height: 1.615 m | Mass: 58.96 Kg

Protocol (5 min/phase Seated rest Warm up 25 wat Stage one 75 wat Stage two 125 wat Cool down 25 wat Seated rest

Heart rate 60 72 80 100 92 68

Blood Pressure 114/62 130/70 132/74 140/80 115/64 114/60

Rate Pressur e Product 6840 9360 10560 14000 10580 7752

Rating of Perceived Exertion 6 8 12 14 11 6

Discussion As expected HR, BP, RPP, & RPE increased as a result of increased load from exercise. There is a significant increase in the metabolic requirement for O2 compared to when at rest. O2 demand by muscles during exercise is 15 – 25x greater than at rest. Two things occur to meet this demand. Cardiac output increases and redistribution of blood flow from inactive organs to the contracting muscles. The need to synthesize ATP to meet the energy demands of the active contracting muscles is met by vasodilation and increase in blood flow to the muscles. Nitric oxide is one of several factors contributing to vasodilation. Nitric Oxide is produced in the endothelium of the arterioles and is important in the auto regulation of muscle blood flow during exercise. The sympathetic nervous system is responsible for regulating increased HR via cardiac accelerator nerves by stimulating release of neurotransmitter norepinephrine. The release of norepinephrine stimulates the SA and AV node. As discussed already BP increases during exercise and this is important because an increase in arterial pressure allows for an increase in oxygen extraction from the blood. Vasoconstriction in the splanchnic, renal, and inactive skeletal muscles occur so that there is more blood supply to the working muscles which require more O2. During the cool down and seated rest after conducting the workout HR, BP, RPP, & RPE decreased as a result of decreased demand for O2. The parasympathetic nervous system is responsible for regulating decreased HR via vagus nerve by stimulating the release of neurotransmitter acetylcoline. The release of acetylcoline inhibits the SA and AV node....