The Human Heart Rate Aim: To study changes in the rate of the human heartbeat. Introduction: Blood is sent pulsing through the body's veins, arteries and capillaries with each beat of the heart. The circulation of blood through the body delivers oxygen and food to the cells and removes wastes. The cells cannot survive if circulation stops for even a small amount of time. With an increase in body movement there is an increase in the cell's energy use and the heart rate must increase to pump enough blood to the cells. Then, as body movement decreases again, so does the heart rate.

The heart muscle can be enlarged with regular vigorous exercise. A larger heart is more efficient than a smaller heart as it is stronger and can hold more blood. The heart is a cardiac muscle and contracts by itself, even when removed from the body. The muscles rhythmic beat is sped up or slowed down by the autonomic nerves that are attached to the heart. The heartbeat has two phases.

Systole is the name given to the contraction phase and diastole is the name given to the relaxation phase. The heart valves slapping closed provides the sound of the heartbeat. Materials. Stopwatch Procedure - Part A 1.

The group sat quietly and relaxed for two minutes. 2. The stopwatch was used to time 30 seconds while the pulse of the members was taken. The pulses were then multiplied by two. Part B 1. The group walked around the building for three minutes.

2. Step 2 of Part A was repeated. Part C 1. The group took part in various forms of vigorous exercise including running, step-ups, running up the stairs and star jumps for three minutes. 2. Step 2 of Part A was repeated.

ResultsRestingBox Rate Box Rate 1 74 15 762 54 16 563 78 17 824 70 18 905 50 19 1086 78 20 607 84 21 708 66 22 769 78 23 8410 78 24 6611 50 25 8012 62 26 8013 74 27 6614 74 28 76 Mild Exercise Box Rate Box Rate 1 94 15 1102 84 16 783 98 17 1004 90 18 985 72 19 1026 84 20 767 76 21 868 88 22 949 94 23 10610 102 24 7211 84 25 9212 90 26 10213 88 27 6814 94 28 86 Vigorous Exercise Box Rate Box Rate 1 150 15 1342 128 16 1323 160 17 1604 120 18 1525 102 19 1546 148 20 1327 124 21 1508 146 22 1489 142 23 15010 24 9811 140 25 15412 128 26 16013 114 27 14814 138 28 152. Individuals involved in regular exercise. Analysis of Results 1. (84 - 54) X 100 = 55. 5542. (128 - 54) X 100 = 173.

037543. 80 X 54 = 4320 mL per minute 4320 X 60 = 259200 mL per hour 4. 80 X 128 = 10240 mL per minute 10240 X 60 = 614400 mL per hour See attached graph. Discussion 1. The individuals who exercise regularly tend to be concentrated in the low area of the histograms. 2.

The individuals who exercise regularly will have a stronger heart and therefore a slower heart rate as it takes less to pump the blood around the body. 3. The range is the greatest in the vigorous exercise section of the graph. Critical Analysis The pray overall was successful but a few things could have been improved.

The pulse was taken only once at each state. If the pulse had been taken three times and an average found it would have been more accurate. Also, the pray was rushed. When individuals found it hard to find their pulse it made them flustered and feel they were holding the class up. This may have raised their heart rate giving an incorrect resting heart rate. If there were more time to do this pray this would not have been a problem.

The readings taken for the mild and vigorous exercise states could have been more accurate as well. If all of the individuals had walked at the same rate and done the same vigorous exercise at the same rate the reading would have been more accurate. These are only a few minor flaws in the pray. It was overall a good pray and very successful. Conclusion The pray was successful in studying the changes in the human heart rate. With many different subjects and levels of fitness in those subjects it gave a wide range of results to study.

The differences in heart size and strength were evident and useful data has been recorded.