How Exercise Can Affect The Heart Rate

Enhancing cardiac output allows you to maintain lower heart rates during physical activity. For example, at the start of a program you may have a heart rate of 150 beats per minute while running at a 6 mph pace. After three or more months of training increased cardiac output enables you to sustain the same running intensity at a lower heart rate such as 125 beats per

Heart rate anticipatory response – this is where the heart rate starts to automatically increase before you start to exercise. The heart rate is able to increase automatically by chemical hormones, the hormones are adrenaline and noradrenaline. These hormones are found inside the brain. The reason the heart rate increase before exercise is because it prepares the muscles for exercise, the reason it prepares the muscles for exercise is because by the heart rate increase the more oxygen is getting to the muscles there fore they will not be needing a such a large oxygen supply all at once. It doesn’t only supply oxygen it supply’s nutrients, the supply of nutrients also provides energy and helps to repair the muscles after exercise. By the heart rate starting to increase gives the heart a head to start pumping hard this enables the heart to not have as much stress on it.

Exercise increases heart rate by a process of sympathetic autonomic stimulation. Sympathetic (adrenergic) nerves increase the excitability of the sino-atrial node and reduce the P-R interval .As exercise continues, the physiological changes in the body are continuously monitored by a number of physiological systems and the balance of activity of the sympathetic system (speeding up) and the parasympathetic system (slowing down) is constantly adjusted. When exercise is over, the heart rate does not drop immediately as the body has to undergo a period of re adaption to return to the resting state.

However with regular exercise people can reach lower rate of heart beat and can creat tighter muscles and stop the strain on their heart.

Stroke volume is the amount of blood pumped out of the heart during each contraction measured in mL/beat. A long term effect of exercise on stroke volume is that it will increase. As the left ventricle grows in size, more blood can be filtered in and out.

The effects of heart rate on differing durations of exercise were studied in this experiment. For people, heart rate tends to increase as they perform physical exercises. The amount of beats per minute gradually increases as people perform physical activities. Heart rates taken before exercise are relatively low, and heart rates taken one minute after exercise increase significantly. Heart rates slowly begin to decrease after they are taken two minutes and three minutes after performing the step test, which is to be expected. The rates of intensity throughout exercise relates with changes in heart rate throughout the step test performed in the experiment (Karvonen 2012). The age of the participants affected the experiment, since the heart rate during physical exercise, in this case the step test, is affected by age (Tulppo 1998).

Introduction: Exercise is a physical activity or particular movement that is used in order to become healthier and stronger. (1) Exercise, in all of its forms, has various effects on the different systems in the human body. One of the main benefits is cardiovascular health, including circulation and heart health. Exercise uses a lot of energy, which the cells derive from oxidising glucose. Meaning that the heart has to work harder to pump more blood throughout the body and the heart has to beat faster in order to achieve a high effort. (2) The heart benefits from exercise include being able to pump more blood through the body and continue working at a higher level with less strain. (3)

During rest or normal physical activity muscles use glucose and break it down to CO2 and H2O to give ATPs (energy) to the muscles to work. This reaction requires oxygen which comes from the blood. Therefore your heart constantly requires to pump oxygenated blood from the lungs to the body muscles and carry back the CO2. the independent variable would be exercise, leaving the heart rate as the dependent variable; thus it is the one that it affected. This lab was to fully understand how the heart is affected by exercise.During exercises, more ATPs are required and hence more glucose is broken down, therefore more oxygen is required. therefore the heart needs to pump oxygenated blood into the muscles faster and Therefore the heart rate increases.

Method and results - The study was compiled of seven female students from the University of Huddersfield. For the exercise a step was used, a polar heart rate monitor was used for each participant with an independent assessor timing the participants, and recording the readings. Results of the study showed there was an increase in heart rate when performing mild exercise.

The effects of exercise on blood pressure, heart rate, respiration rate and electrical activity of the heart were assessed. The measurements of respiration rate, pulse rate and blood pressures were noted as described in Harris-Haller (2016). Data was first taken from subjects in a relaxed position and then followed by sets of reading after exercising based on one minute intervals. The data also noted sitting ECG traces from Harris-Haller (2016). The respiratory rate, pulse, blood pressure, P wave, QRS complex and T wave were defined for each subject. The class average was calculated for males and females and graphed to illustrate the results by gender for each cardiopulmonary factor.

As the intensity of exercise increased, so did the rates of the heart and breathing. After a small period of rest, the heart rate and breathing rate both decreased to a point close to their resting rate. This proved the stated hypothesis. First, the hearts average resting rate was recorded to be 76 bpm. The heart is therefore transporting oxygen and removing carbon dioxide at a reasonably steady rate via the blood. During the low intensity exercise (Slow 20) the heart rate increases to 107 bpm, which further increases to 130bpm at a higher intensity level (Fast 20). The heart therefore needs to beat faster to increase the speed at which oxygen is carried to the cells and the rate at which carbon dioxide is taken away by the blood.

The literature on the effects of exercise of cardiac output maintains the idea that exercise should affect cardiac output- pulse rate, systolic blood pressure, diastolic blood pressure, QRS-pulse lag, P-T and T-P intervals, because of increased heart rate. For our experiment, we tested this theory by measuring our cardiac output before and after some rigorous exercise. We measured the individual cardiac output and then combined the data to compose a class-wide data average. We compared the results of the experiment to what we expected, which was that exercise does affect our heart. Our data from this experiment supported the notion that exercise does, in fact, change cardiac output.

I predict that during exercise the heart and respiratory rate (RR) will increase depending on the intensity of exercise and the resting rates will be restored soon after exercise has stopped. I believe that the changes are caused by the increased need for oxygen and energy in muscles as they have to contract faster during exercise. When the exercise is finished the heart and ventilation rates will gradually decrease back to the resting rates as the muscles’ need for oxygen and energy will be smaller than during exercise.

The amount of blood pumped out during systole is called the stroke volume and is less than the end diastolic volume because the ventricles do not completely empty themselves during systole. At all levels of physical activity stroke volume is increased. There is an improvement in ventricular performance with an increase of plasma volume [4] and a faster peak lengthening the rate of the left ventricle during diastole [6]. Training can improve stroke volume but by no more then about 20%. Due to the decreased heart rate an increase of ventricular filling will result and an increase in ventricular volume and thickening of ventricular walls thus

The muscles demand more energy and oxygen due to the increased workload that comes from exercise. This causes the heart rate and respiratory rate to increase in order to provide the required additional fuel to the muscles. In addition, the entire circulatory system works more efficiently due to vascular dilation and cholesterol reduction. By improving the condition of your cardiovascular fitness you are also helping yourself live longer, decrease the risk of heart disease, lower blood pressure, strengthen your cardiovascular system, and the list goes on. These reasons alone could save you from having heart disease.