The effect of exercise on blood pressure

The effect of exercise on blood pressure Introduction: The Cardiopulmonary System is the system in the body that is responsible for collecting and distributing oxygen to all parts of the body for use in cellular respiration and is also for removing the waste carbon dioxide that the body produces after burning the oxygen. This system is comprised of the respiratory and circulatory systems which include the heart, lungs, veins, arteries, and capillaries. The respiratory system is what collects the oxygen from the outside environment and expels CO2 through breathing. When someone breaths they inhale oxygen into their lungs and exhale CO2 out of their lungs. The circulatory system is the organ system that transports the bodys blood throughout itself. The blood carries important materials like oxygen and carbon dioxide to every inch of the body. The heart is a muscle about the size of a clenched fist and weighs approximately 10.5 ounces (Science Clarified 2010). It is the control center of the circulatory system and moves the blood to the lun gs and the other parts of the body through contracting and relaxing itself in a rhythm that keeps blood constantly traveling in the body. The way the cardiopulmonary system works is the heart is always pumping blood through its 4 chambers (right and left atrium and ventricles) and out through arteries out to the body. The right atrium and right ventricle pumps CO2 rich and O2 poor blood to the lungs, where thinner blood vessels called capillaries absorb oxygen from the lungs and releases its CO2 into the lungs. The oxygen rich blood returns to the heart through veins into the left atrium and then the left ventricle. The oxygen rich blood is then pumped out into more arteries that take the blood to other organs and parts of the body. The oxygen is released into the cells through thin capillaries again, and then return as oxygen poor and carbon dioxide rich blood returns to the heart. The functions of the cardiopulmonary system can be measured by taking a humans heart rate and blood pressure. The heart rate or pulse is how many times a humans heart beats per minute. The heartbeat can be measured only through arteries, because when the heart contracts, the forced blood causes pressure that can be felt in the arteries, known as arterial pressure. Veins traveling back to the heart have much thinner walls and therefore dont have enough pressure from the heart pumping to be used to measure pulse. The pressure within veins is affected by conditions outside the vessels themselves, such as contraction of surrounding skeletal muscles (Weedman and Sokoloski 2009). Blood pressure is taken by measuring a persons diastolic pressure and systolic pressure. The diastole is the period of the hearts pumping cycle when the atria and ventricles fill and the heart relaxes. The systole is when the heart contracts and forces the blood out of the heart. The total elapsed time for a compl ete cycle of both the atria and the ventricles is 0.8 second (Fredrick and Pauline 1987). In this lab, the question for the experiment was how exercises will affect your blood pressure and pulse. The hypothesis tested was walking up or down four flights of stairs will increase blood pressure and pulse, unlike the null hypothesis that blood pressure and pulse after walking up or down the stairs will not be affected. We hypothesized that blood pressure and pulse will increase because walking up or down stairs requires more energy than a body at rest. This exercise requires the heart pump blood faster in order to supply more oxygen to the body to provide the energy to walk up and down the stairs. The importance and relevance of this experiment is that someone who is unhealthy and prone to a heart attack may be at risk of suffering an attack while walking up flights of stairs if it raises blood pressure and heart rate. Methods and Materials: The experiment was done in a building with four flights of stairs, with 24 participants from our class separated into groups of two. The two partners had a sphygmomanometer that measured blood pressure and pulse, and a pencil and paper to record pulse and blood pressure. The heart rate and blood pressure was tested for walking up and down the stairs by making partner one walk up four flights as partner two waited at the top of the stairs. When partner one reached the top, partner two was there too measure partner ones heart rate and blood pressure using the sphygmomanometer. The inflatable cuff on the device was attached to the partners upper arm and inflated. The cuff was then deflated as the sphygmomanometer analyzed the blood pressure and pulse from the partners artery running down their arm. Partner two measured the blood pressure and pulse once after partner one reached the top of the stairs, then again after two minutes passed, and after four minutes passed. The same process wa s taken for the other partner walking down the stairs. The independent variable was the subject either walking up or down the stairs. The dependent variable was each partners heart rate and blood pressure. After the experiment, we gathered the data from everyone in the class and averaged their results and compiled the data into tables and graphs for interpretation. Results: The results from the participants of the experiment were that on average, after each partner did their exercise, their blood pressure and heart rate increased. Comparing walking up the flights of stairs to walking down however, our results showed that walking up stairs increased blood pressure and pulse more than walking down the stairs. Our classs averages are compiled in the data table below. The data from the table is also displayed on graphs to show the trend of blood pressure and pulse. T-tests were done on the data from the basal reading to 0 minutes after walking up or down the stairs and from 0 minutes after to 4 minutes after walking up or down the stairs. The t-tests show the probability that the results from walking up or down starts are based on chance, or if there is significance to the results. If the P value of each t-test is greater than .05 then the results are based on chance and are insignificant. Data Table: Pulse (bpm) Down Up Basal 71.5 67.7 0 min post 72.6 88.6 2 min post 73.6 67.2 4 min post 73.9 70.3 Systolic BP (mm Hg) Basal 113.3 119.3 0 min post 121 141 2 min post 119 122 4 min post 112 123 Diastolic Bp (mm Hg) Basal 71.3 71 0 min post 76 91 2 min post 77 81 4 min post 78 78 T-Tests: T-Test T-Test Down T-Test Up Pulse Rate Basal- 0 Min. 0.646774259 0.021762917 0 Min. 4 Min. 0.628728428 0.032305937 Systolic Blood Pressure Basal- 0 Min. 0.04246026 0.002469184 0 Min. 4 Min. 0.017651827 0.000671518 Diastolic Blood Pressure Basal- 0 Min. 0.074034579 0.000739125 0 Min. 4 Min. 0.567643162 0.001016322 Graphs: According to the averages in blood pressure and pulse, the graph and data tables show that walking up stairs increases the blood pressure and pulse more than walking down the stairs. The T-test for each measurement says that in the majority of the data Discussion: Before the experiment, I hypothesized that when someone walks up or down the stairs, it would increase the persons blood pressure and pulse. The experiment results instead only supported the hypothesis that walking up the stairs increases blood pressure and pulse, but the data and t-tests showed for walking down stairs showed that it wasnt a significant increase. My hypothesis wasnt fully correct and a more appropriate hypothesis would have been that walking up the four flights of stairs would increase blood pressure and pulse more than walking down the same amount of stairs. This is because while walking upstairs the body has to work against the force of gravity which is more energy consuming than walking down stairs. This explains our results that after walking up the stairs, the subject tested had a higher blood pressure (141/91) and pulse (89) than the subject who walked down the stairs (BP 121/76 Pulse 72). The heart had to pump faster and with more force going up the stairs to move oxygen faster to the parts of the body and thus raised the bodys blood pressure and pulse. Some errors that manipulated the results were the two being tested had different features like height, weight, shape, and health. These differences would lead to different results because someone that is in better physical condition would not have as high a blood pressure and pulse than someone who isnt as fit. This is because their heart is stronger and doesnt need to work as hard to supply the body with the right amount of oxygen. The entire class also had a range of body types all in different physical shape that also could have affected results. Also the partner who walked down the stairs did not get measured on time for the 2 minute and 4 minute measurements and the sphygmomanometer didnt always properly read the subjects blood pressure and pulse properly. If this experiment was to be repeated it would be better if only one person walked up and down the stairs, and that there was a control measurement of the persons pulse and blood pressure before they walk up the stairs and are at rest. Cited Literature: Cornett D. Frederick, Gratz Pauline. 1987. Modern Human Physiology. United States: Holt, Rinehart and Winston, Publishers. p 337. Science Clarified, Circulatory System, http://www.scienceclarified.com/Ci-Co/Circulatory-System.html, Sept. 7, 2010. Weedman, Sokoloski. 2009, Biology of Organisms A Laboratory Manual for LIFE 103. Mason OH: Cengage Learning. p 176.