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Right after exercise, is the amplitude of the pulse smaller or bigger than resting period? And why is that ?
I would guess that pulse pressure increases after exercise. As I understand it,
- Systolic pressure is simply resistance against the pressure wave of the ejected blood. Since the stroke volume is increased in exercise to deliver more blood, systolic pressure will be definitely be increased.
- During diastole, the major resistance to flow is due to peripheral resistance (major arteries now assist flow by releasing stored energy), and this is reduced in exercise due to vasodilation. Although there is more flow, since the resistance is markedly reduced, diastolic pressure may drop.
Hence, pulse pressure should increase.
Michael C. Stevens , . Francesco Moscato , in Mechanical Circulatory and Respiratory Support , 2018
Aortic pressure (AoP) is normally maintained by the baroreflex, which adjusts vascular resistance, venous tone, HR, and contractility [ 30 ]. However, this mechanism may be diminished in heart failure, partly due to reduced ventricular contractility. Adjusting pump speed to maintain AoP may compensate for a reduced baroreflex mechanism. This approach was proposed by Wu and colleagues as a primary control objective [ 31–33 ]. This controller's secondary objective was to maintain constant ΔP control. The reasoning behind this is that if afterload and pump △P are constant, then by extension LVAD inlet pressure must be constant as well, which may aid with suction prevention. Evaluation was performed in silico and in vitro, albeit with inconsistent evaluation protocols. In silico, the controller was subject to step changes in systemic vascular resistance (SVR) and then to a transition from rest to exercise. In vitro, only changes in contractility were simulated. This approach required estimation or measurement of two pressures in order to prevent suction and maintain perfusion. This control strategy appears to be quite beneficial however, its performance has been compared only to a simulated healthy left ventricle.
A&P Lab Report on Blood Pressure & Pulse during exercise
Topic: Human Cardiovascular Physiology- Blood Pressure and Pulse Rate Determination.
Hypothesis: Exercise can raise the blood pressure and the pulse rate.
Aim: To determine the effect of exercise on the blood pressure and the pulse rates of students in the class.
Introduction: The blood pressure of a person is the force exerted by the blood on the walls of the arteries per unit area. The blood pressure unit is mmHg. The blood pressure of an individual is expressed in two ways, the systolic (due to the contraction of the ventricle) and diastolic, (due to the relaxation of the ventricle). The normal blood pressure of an individual is 120/80 (systolic / diastolic). Various factors can alter a person's blood pressure this includes exercise, smoking, stress, diseases and age.
Stepping stool, timer, blood pressure measurement kit (Sphygmomanometer and a stethoscope) and students in-groups of four. In each group one student acted as a patient, while the other acted as a physician or nurse. Another acted as the timekeeper. The fourth student acted as the data recorder.
The base-line pulse rate and blood pressure of the patient (student) were obtained. The patient was asked to perform stepping - up and down the stool 30 X within 5 minutes. After the stepping stool exercise, the patient's blood pressure and pulse rate were immediately obtained again. After resting for 2 minutes, the measurements were repeated and also after 5 minutes.
In order to obtain more data each student in the group acted as a patient and the measurements were repeated.
During exercise it was observed that the breathing rate of the student had increased. As a result, the demand for oxygen and energy had increased. The most efficient way to meet these needs involved the use of oxygen to break down glucose. This occurred when one glucose molecule and six oxygen molecules combined to produce ATP, a usable source of energy. This process also produced carbon dioxide molecules. Also, it was observed that the participants breathing rate increased, in order to facilitate the removal of carbon dioxide and increase the oxygen level inside the lungs to be transported by the haemoglobin molecules to actively working muscle cells. Based on the results show in the table, when the intensity of the exercise activity had decreased and the student was allowed to rest, the breathing rate had slowed down .This occurred because the body was no longer subjected to strenuous exercise activities , which demanded high intake of oxygen. As a result, oxygen intake occurred at a normal breathing rate.
Heart rate can be defined as the average number of heart beats per minute and can be monitored using a stethoscope. A heart beat occurs when the heart contracts to pump blood through the body. There is a relationship between breathing rate and the heart rate . During exercise the muscles, body cells and enzymes (which are denaturing due to higher body temperatures - in simple terms your metabolic rate is vastly decreasing) required more energy because the body was working harder , and so during RESPIRATION there was a demand for more oxygen and frequent removal of Carbon dioxide.
The heart had to pump harder to get more oxygen to these cells, and to remove the carbon dioxide inside the blood which goes up to the lungs to get oxygenated and then returns to "offload" deoxygenated blood. Hence, breathing rate increased in order to get the blood oxygenated and get rid of this carbon dioxide. Thus, the heart pumped at a quicker rate to get this oxygen into its cells. After, an exercise, the heart rate gradually decrease and oxygen intake occurred at a normal level.
Exercise and Your Heart
Your heart is a muscle — and just like the other muscles in your body, it gets stronger with exercise. Kaiser Permanente explains that when your heart gets stronger, it pushes out more blood with every beat — which means it doesn't have to work as hard to circulate adequate oxygen and nutrients when you exercise. So your heart rate will still rise with exercise, but it won't have to rise as much.
Regular exercise helps the rest of your circulatory system get more efficient too. This includes greater ability to utilize oxygen, better blood flow in small arteries around your heart and an improved cholesterol profile.
As Kaiser Permanente notes, if you haven't exercised in a long time or have a history of high blood pressure, stroke, dizziness, heart disease or exercise-related pain, you should talk to your doctor before working out.
Your resting heart rate can provide a useful glimpse into your heart health. Count your pulse for 60 seconds, after a good night's sleep and before you get out of bed. The result is your resting heart rate.
As the American Heart Association (AHA) notes, for most people who are sitting or lying down — calm, relaxed and not ill — a resting heart rate of 60 to 100 beats per minute (bpm) is normal. Your resting heart rate might be lower if you take certain drugs, such as beta blockers. Athletic people may also have lower resting heart rates, down to about 40 bpm, because their entire circulatory system works more efficiently.
The AHA warns that if you have a very low pulse or if you have frequent episodes of unexplained fast heart rates — especially if you also feel weak, dizzy or faint — you should consult a doctor to determine whether you're having a medical emergency.
A heartbeat is a duration taken for your heart to be filled with blood and contracts to pump it to your body. Medically, the speed of your heartbeat is referred to as heath rate. Therefore, heart rate is the speed of the heartbeat measured by the number of contractions of the heart per minute.
According to the American Heart Association, all things being equal, the normal heart rate of every adult is 60-100 bpm. Heart rate above 100bpm is known as tachycardia and heart rate below 60 is known as arrhythmia.
So during exercise, the heart does more work than when the body is at rest. The heart pumps blood faster than normal thereby increasing the heartbeat. Increase in heartbeat leads to an increase in heart rate
Blood pressure is the pressure of blood against the blood vessel walls during the cardiac cycle it is influenced by a variety of factors.
Describe the process of blood pressure regulation
- Normal blood pressure for a healthy adult is 120 mm Hg during systole (peak pressure in the arteries ) and 80 mm Hg during diastole (the resting phase).
- Blood pressure is regulated in the body by changes to the diameters of blood vessels in response to changes in the cardiac output and stroke volume.
- Factors such as stress, nutrition, drugs, exercise, or disease can invoke changes in the diameters of the blood vessels, altering blood pressure.
- cardiac output: the volume of blood being pumped by the heart, in particular by a left or right ventricle in the time interval of one minute
- hydrostatic: of or relating to fluids, especially to the pressure that they exert or transmit
- stroke volume: the volume of blood pumped from one ventricle of the heart with each beat
Blood pressure is the pressure of the fluid (blood) against the walls of the blood vessels. Fluid will move from areas of high to low hydrostatic pressures. In the arteries, the hydrostatic pressure near the heart is very high. Blood flows to the arterioles (smaller arteries) where the rate of flow is slowed by the narrow openings of the arterioles. The systolic pressure is defined as the peak pressure in the arteries during the cardiac cycle the diastolic pressure is the lowest pressure at the resting phase of the cardiac cycle. During systole, when new blood is entering the arteries, the artery walls stretch to accommodate the increase of pressure of the extra blood. During diastole, the walls return to normal because of their elastic properties.
Blood pressure values are universally stated in millimeters of mercury (mm Hg). The blood pressure of the systole phase and the diastole phase gives the two readings for blood pressure. For example, the typical value for a resting, healthy adult is 120/80, which indicates a reading of 120 mm Hg during the systole and 80 mm Hg during diastole.
Relationship between blood pressure and velocity: Blood pressure is related to the blood velocity in the arteries and arterioles. In the capillaries and veins, the blood pressure continues to decease, but velocity increases.
Blood Pressure Regulation
Throughout the cardiac cycle, the blood continues to empty into the arterioles at a relatively even rate. However, these measures of blood pressure are not static they undergo natural variations from one heartbeat to another and throughout the day. The measures of blood pressure also change in response to stress, nutritional factors, drugs, or disease. The body regulates blood pressure by changes in response to the cardiac output and stroke volume.
Cardiac output is the volume of blood pumped by the heart in one minute. It is calculated by multiplying the number of heart contractions that occur per minute (heart rate) times the stroke volume (the volume of blood pumped into the aorta per contraction of the left ventricle). Therefore, cardiac output can be increased by increasing heart rate, as when exercising. However, cardiac output can also be increased by increasing stroke volume, such as if the heart were to contract with greater strength. Stroke volume can also be increased by speeding blood circulation through the body so that more blood enters the heart between contractions. During heavy exertion, the blood vessels relax and increase in diameter, offsetting the increased heart rate and ensuring adequate oxygenated blood gets to the muscles. Stress triggers a decrease in the diameter of the blood vessels, consequently increasing blood pressure. These changes can also be caused by nerve signals or hormones even standing up or lying down can have a great effect on blood pressure.
Changes in Cardiovascular System during Exercise | Human | Biology
In this article we will discuss about the changes which occurs in cardiovascular system during exercise.
Prolonged and systematic exercise causes enlargement of the heart, and this is happens only to cope with the excessive work load imposed upon the heart during work. There is a lot of misunder­standing that prolonged exercise may cause dilatation of the heart similar to that happens in heart disease. But the hypertrophy of the heart in athletes is caused by physiological processes.
The nature of processes is similar to the hypertrophy of skeletal muscle resulting from systematic exercise. Thus hypertrophied athletic heart is more powerful, efficient and capable of greater increase in stroke volume but the dilated diseased heart is less efficient and has a limited capacity for work.
II. Heart Rate Changes during Exercise (Fig. 7.112):
The acceleration of the heart is observed immediately fol­lowing exercise. It has been observed that the heart rater is increased slightly even before onset of exercise and it is presumably due to influence of the cerebral cortex on the medullary cardiac centre. A short rise of heart rate is observed at first minute of exercise but after that this rate of rise is slight decreased.
Within 4 to 5 minutes of exercise the maximal rise is more or less achieved. A ‘plateau’ is observed if the exercise is further continued. But the time is variable from individual to individual and even with different degrees of work load. In athletes, the rate of rise of the heart will be slower.
Besides these, maximal heart rate that is reached during exercise and the rapidity with which the maximal value is attained depends upon several factors which are:
(b) Environmental temperature and humidity, and
(c) Physical conditions of the subjects.
There is no satisfactory explanation of the increase of heart rate in man during exercise. The explanation is mostly based on the animal experimentation. It is claimed that both nervous and chemical factors are playing in such process. Initial rise of heart rate (anticipatory heart rate) just before exercise is due to the influence of cerebral cortex and other higher brain centres.
With the onset of exercise the rise of heart rate may be due to:
(a) Reflexes originating in the receptors of moving joints or contracting muscle,
(b) Stimulation of chemoreceptors in muscles by the acid metabolites,
(c) Sympathetico-adrenal activation causing section of much larger amounts of epinephrine in the blood,
(d) Rise of body temperature, and
(e) Stimulation of stretch receptors in atrium by the rapid venous return in heart thus causing Bainbridge reflex.
There is controversial opinion regarding the Bainbridge reflex. None does believe that the increase of heart rate during exercise is due to the effect of such reflex, because during the right atrial pressure does not rise and if it is so then instead of rise there is possibility of increase of heart rate.
Regarding the return of heart rate to initial resting level depends upon the intensity of work load and also on the physical condition of the individual. The rapidity with which the heart rate returns to the resting level following cessation of exercise is considered as a test for physical fitness. In trained individual or in physically fit person the recovery period is very short.
During exercise the cardiac output is greatly increased. In trained athletes, it may achieve a maximal output of 30 litres per minute, at an O2 uptake of 4 litres per minute but in non-athletes, the output may be average 22 litres at an O2 uptake of 3.3 litres per minute. The exercise in cardiac output during exercise is the result of the increase in stroke volume and heart rate.
It has been claimed for a long time that the increased stroke volume during exercise is due to functioning of Starling law of heart. But Starling law of heart cannot hold good because modern technique claims that the diastolic size of the heart is not increased during exercise. Instead, the diastolic size of the heart is decreased during exercise so that the increased stroke volume cannot be caused by greater stretching.
Besides this, Rushmer (1959) has claimed that the increased cardiac output during exercise does not necessarily involve increase in stroke volume and heart rate. He claimed that the stroke volume during exercise is increased no doubt, but by about the same amount on changing from standing to the supine position. He claimed that increase in cardiac output is mostly due to increase of heart rate.
Venous return is greatly increased during exercise for the following reason:
(a) Milking or Massaging Action of Skeletal Muscles:
During exercise, the alternate contraction and relaxation of the muscle act as a booster pump for flowing blood towards the heart. Due to presence of valves in the veins, the blood is squeezed out from the vein towards the heart during contraction and allowed to fill blood during relaxation of the muscle. This pumping mechanism depends upon intensity and type of exercise,
(b) Respiratory Movements:
Respiratory movements exert a sucking effect over the right heart and great veins so that greater venous return may occur. Visa fronte is the consequence causing of the above effect during respiratory effort. During inspiration the thoracic cavity is enlarged causing fall of intrathoracic pressure. This fall of intrathoracic pressure as well as increase of pressure on the anterior abdominal wall due to descent of diaphragm cause rapid return of blood into the heart. Expiration has got the opposite effect, and
(c) Contraction of Limb Veins:
It is claimed that limb veins undergo reflex vasoconstriction during exercise thus facilitating rapid venous return to the heart.
Blood pressure is raised with the onset of exercise. There may be an anticipatory blood pressure due to nerve impulses originating from the cerebral cortex to the medullary cardiac and vasocon­strictor centres. Other factors that may participate in the rise of blood pressure during exercise are due to activation of sympathetico adrenal systems causing shifting of blood from the splanchnic beds to the other parts of the body.
So the rise of arterial blood pressure during exercise is due to:
(a) Increase of cardiac output, causing greater distention of aorta and large arteries,
(b) Increase of heart rate, and
(c) Compensatory vasoconstric­tion in the non-active organs (splanchnic beds and skin) and vasodilatation in the active organs so as to perfuse the active organs with a greater pressure.
The nature of blood pressure rise cannot be generalised because the pressure changes mostly depend upon the type, speed and duration of the activity and also of the physical condition of the subject.
VI. Circulatory Status During Exercise:
During exercise, the circulation is adjusted in such a way that the active muscles as well as the vital organs get blood supply to a greater proportion than that of the inactive organs and the non-vital organs. It has been observed that the active muscle gets more blood supply during exercise and the circulation is increased more than about 30 times (Fig. 7.113).
It is claimed that this greater supply is due to decrease of vascular resistance caused by locally accumulated metabolites. During exercise sudden lack of O2 caused the increased accumulation of CO2, lactic acid, adenosine, intracellular K + and histamine. These substances may cause hyperaemia (reactive hyperaemia) and thus the resistance to blood flow is decreased.
As the work load of the heart is increased tremendously during exercise, the coronary flow is increased accordingly to its own nourishment, otherwise hypoxia may prevail. So in moderate exercise, coronary flow is increased according to the O2 requirement of the cardiac muscle. But in severe exercise, the coronary flow may be increased no doubt, but the cardiac muscle due to tremendous increase of heart rate, will fail to maintain its O2 according to its need and the subject may feel anginal pain.
Pulmonary circulation during exercise is increased in proportion to the increase in venous return to the heart. But with the increase of pulmonary circulation, the pulmonary arterial pressure is insignificantly increased possibly due to distensibility of its blood vessels. Blood flow to the brain is relatively under normal state and remains mostly unaltered during exercise.
During exercise the blood flow in the active muscle, lung, heart is increased, but the same in the abdominal organ, kidneys and in the skin (initially) is greatly decreased due to compensatory vasoconstriction. This happens possibly through the chemoreceptor reflex initiated by the accumulated metabolites during exercise so as to cause redistribution of blood from abdominal organs to the exercising muscle, heart, lung and skin (later stage). Skin blood flow is initially decreased but as the work is continued and the body temperature is increased the skin blood flow is also increased only to eliminate excess heat produced by the contracting muscle.
When you finish exercise, your parasympathetic nervous system slows your heart rate, breathing rate and blood pressure to return your heart rate to resting levels 1. This system undergoes a training effect after you consistently spend time in exercise. The parasympathetic nervous system becomes more efficient and will slow your heart rate quicker as you become more physically fit.
How Long for Your Blood Pressure to Return to Normal After Running?
Your heart undergoes a training effect as you exercise and becomes more efficient in pumping out necessary oxygen. One of the benefits of exercise training is that your heart pumps out more blood with each beat, so it does not have to beat as often as it did when you were untrained. This causes your training heart rate to be lower, so your return time to your resting level will be shorter.