Heart Rate And Systolic Blood Pressure example essay topic

Abstract The aim of the study was to investigate the effects exercise had on heart rate, systolic and diastolic blood pressure. The aim was to compare heart rate, systolic and diastolic blood pressure between lying supine and when cycling at 100 W intensity and to detect any significant differences. The group of subjects comprised 10 first year Sports Science male (n = 7) and female (n = 3) students. Measurements of subjects heart rate and blood pressure were recorded when lying supine and in the final minute of a 5 minute bout on a cycle ergometer at exercise intensity 100 W. During exercise heart rate needs to increase so as to increase the amount of oxygen to working muscles and to get rid of waste products such as carbon dioxide and lactic acid. During exercise it is due to an increase in cardiac output that blood pressure rises; systolic pressure rising quickly and then evening out and diastolic pressure reasonably unaffected. The heart rate readings showed a group result (mean +/- S.D.) of 125.1 +/- 6.8 beats per minute when lying supine and 146.8 +/- 9.1 beats per minute at exercise intensity 100 W. The systolic blood pressure readings showed a group result of 125.1 +/- 6.8 mmHg when lying supine and 146.8 +/- 9.1 mmHg at exercise intensity 100 W. The diastolic blood pressure readings showed a group result of 75.7 +/- 8.4 mmHg when lying supine and 112.1 +/- 18.9 mmHg at exercise intensity 100 W. To conclude, there was significant difference between subject's heart rate (.

000), systolic blood pressure (. 000) and diastolic blood pressure (. 001) when lying supine and when at exercise intensity 100 W. Introduction The cardiovascular system makes sure that blood is constantly distributed to the body. The heart acts as the one main cardiovascular pump.

Blood leaves the heart via arteries and returns via veins. Cardiac output (CO) is the volume of blood that each ventricle manages to pump out per minute. Cardiac output is the result of stroke volume (SV) and heart rate (HR). Therefore, CO (ml / min ) = SV (ml / beat ) x HR (beats / min ). 'The average resting heart rate in an adult is 70 beats per minute; the average stroke volume is 70 to 80 ml per beat' (Van de Graaff & Fox, 1999, p. 656). During exercise heart rate needs to increase so as to increase the amount of oxygen to working muscles and to get rid of waste products such as carbon dioxide and lactic acid.

Three factors are associated with an increase in heart rate: neural control, hormonal control and intrinsic control. Before the onset of exercise heart rate will begin to increase. This is caused by the release of adrenaline into the bloodstream which stimulates the Sinuatrial (SA) node. At the onset of exercise muscle receptors in the working muscles stimulate the cardiac control centre to increase heart rate. During exercise chemoreceptors in the working muscles and carotid arteries sense an increase in chemicals such as carbon dioxide and lactic acid. These receptors stimulate the cardiac control centre to increase heart rate.

An increase in venous return will further stimulate the SA node to increase heart rate. 'Blood pressure is the force per unit area exerted on the wall of a blood vessel by its contained blood' (Marie, 2001, p. 727). At rest, during ventricular contraction (systole), the average pressure exerted by the heart of a young adult to move blood through the vascular system is about 120 mmHg. During ventricular relaxation (diastole), the average pressure exerted reduces to about 80 mmHg. 'Increased blood flow during moderate exercise causes systolic pressure to rise rapidly in the first few minutes of exercise and level off, usually between 140 to 160 mmHg, while diastolic pressure remains relatively unchanged (McArdle et al, 1994 p. 246). During exercise vasodilation occurs in skeletal muscle thus reducing friction and blood pressure.

It is due to an increase in cardiac output that 'negates this effect of vasodilation' (Honey bourne et al, 1996) and thus increases blood pressure overall. The aim of the study was to investigate the effects exercise had on heart rate and systolic and diastolic blood pressure. The aim was to compare heart rate, systolic and diastolic pressure between lying supine and when cycling at 100 W intensity and to detect any significant differences. Cycling is a rhythmic muscular activity and causes dilation of blood vessels in working muscles.

As a result of this blood flow is increased through a large part of the body and is therefore likely to increase heart rate and systolic blood pressure whereas diastolic blood pressure will stay reasonably unaffected. Method The subjects comprised 10 first year Sports Science male (n = 7) and female (n = 3) students. Their mean (+/- S.D.) age and body mass were as follows: males, 20.1 +/- 1.1 years and 81.6 +/- 9.5 kg, respectively; females, 19.7 +/- 0.6 years and 60.9 +/- 4.5 kg, respectively. Measurements of subjects heart rate and blood pressure were recorded at rest. Using a Polar heart rate monitor (S 610, Polar Electro, Finland), each subjects heart rate (HR) was measured over a 2 minute period when they were lying supine and standing. Once the measurements were completed the heart rate readings were taken from the monitor and recorded.

Using a Sphygmomanometer (Omron M 4, Healthcare Europe, Holland), each subjects blood pressure (BP) was measured when they were lying supine and standing. The inflatable cuff was fitted on the upper arm, with the lead facing down over the brachial artery. The MODE button was pressed followed by the START button on the monitor to start inflation of the cuff. Once the measurements were completed the systolic and diastolic pressure readings were taken from the monitor and recorded. Measurements of subjects heart rate and blood pressure were recorded during exercise. Subjects performed a 5 minute bout of exercise on a cycle ergometer (Mon ark 818 E, Var berg, Sweden) at an exercise intensity of 100 W. During the final minute heart rate was recorded using a Polar heart rate monitor (S 610, Polar Electro, Finland) and blood pressure was recorded using a Sphygmomanometer (Omron M 4, Healthcare Europe, Holland).

Once the measurements were completed the heart rate readings and the systolic and diastolic pressure readings were taken from their respective monitors and recorded. All data was described as the mean (+/- S.D.) unless otherwise stated. The SPSS (Statistical Package for Social Sciences) was used to analyse the subjects results. Paired samples t-tests were used to compare, and detect significant differences between, subjects heart rate, systolic pressure and diastolic pressure when lying supine and when cycling at intensity 100 W. Results Table 1. Subjects heart rate, systolic and diastolic blood pressures and mean +/- S.D. values when lying supine and at exercise intensity 100 W Subject Number: 1.2. 3.4. 5.6. 7.8.

9.10. Mean Std. Dev. Figure 2. Figure 3. From the result table (Table 1.) and paired samples test (Figure 6.) it can be concluded that there was significant difference between subject's heart rate when lying supine and when at exercise intensity 100 W. The paired samples test (Figure 6.) showed a result of.

000 and the result table (Table 1.) showed a result of 68.9 +/- 10.8 beats per minute (mean +/- S.D.) when lying supine and 116.8 +/- 19.2 beats per minute at exercise intensity 100 W. From the result table (Table 1.) and paired samples test (Figure 9.) it can be concluded that there was significant difference between subjects systolic blood pressure when lying supine and when at exercise intensity 100 W. The paired samples test (Figure 9.) showed a result of. 000 and the result table (Table 1.) showed a result of 125.1 +/- 6.8 mmHg when lying supine and 146.8 +/- 9.1 mmHg at exercise intensity 100 W. From the result table (Table 1.) and paired samples test (Figure 12.) it can be concluded that there was significant difference between subjects diastolic blood pressure when lying supine and when at exercise intensity 100 W. The paired samples test (Figure 12.) showed a result of. 001 and the result table (Table 1.) showed a result of 75.7 +/- 8.4 mmHg when lying supine and 112.1 +/- 18.9 mmHg at exercise intensity 100 W. For there to be any significant difference between the two variables, the p-value must be.