The Effect Of Exercise On The Heart

B. Part B. PowerPhys Experiment 4 – Effect of Exercise on Cardiac Output (13 points total)

Four interval times (PR, RT, TP and RR) measured in seconds were recorded both with the subject at rest and after the subject had exercised. The PR and RT intervals remained virtually unchanged with the PR intervals remaining the same both before and after exercise with an interval time of 0.15 seconds, and the RT interval increase by 0.01 seconds from 0.37 at rest to 0.38 seconds after exercise. More substantial changes were noted in TP and RR intervals. The TP interval decreasing from 0.32 seconds at rest to just 0.08 seconds after exercise, a decrease of 0.24 seconds (just 25% of the resting 0.32 seconds). The RR interval decreased from 0.84 seconds at rest to 0.61 seconds seconds after exercise, a decrease of 0.23 seconds

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.

Research Question: What is the effect of practicing aerobic sports on a daily basis, on the recovery heart rate of people?

Being knowledgeable about the heart is very important, especially if one is an athlete. This experiment is significant, because it can tell us how important it is for one to keep their heart healthy. It will also tell us how playing a sport can benefit one’s health and the well being of their heart. Our hypothesis says, if the athleticism of a person increases, then the heart rate recovery time will decrease when heart rate recovery in a function of athleticism. The purpose of this project is to see which type of athlete, or non-athlete has the best heart function.

Introduction: Our bodies need to be in balance in order to function properly, and there are many ways the body maintains balance, or homeostasis. Homeostasis is the maintenance of nearly constant conditions in the internal environment. Our normal heart rate is an example of our body in homeostasis and any sort of change, or stimulus, can alter it. Exercise, adrenaline in the blood, and a low blood pH are all stimuli that increase the heart rate. Exercise, for example, stimulates stretch receptors in the muscles. These receptors then send a signal to a part of the brain called the medulla oblongata that receives the sensory input. It then in turn sends nerve impulses to the sinoatrial node

Investigating the Effect of Exercise on Pulse Rate Aim: To see what happens to the pulse rate during exercise. Prediction: I predict that the pulse rate will increase in order to take more oxygen for respiration. The heartbeat will increase and become stronger to transport oxygen and carbon dioxide to and from the muscle cells. The breathing rate will increase in order to get rid of the extra waste such as Carbon dioxide. Respiration is the release of energy.

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.

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.

Introduction: In this experiment, cardiovascular fitness is being determined by measuring how long it takes for the test subjects' to return to their resting heart rate. Cardiovascular fitness is the ability to "transport and use oxygen while exercising" (Dale 2015). Cardiovascular fitness utilizes the "heart, lungs, muscles, and blood working together" while exercising (Dale 2015). It is also how well your body can last during moderate to high intensity cardio for long periods of time (Waehner 2016). The hypothesis is that people who exercise for three or more days will return to their resting heart rate much faster than people who only exercise for less than three days.

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.

The homeostatic response is the equilibrium between the inside of the body and its external extremities. Exercise affects the body temperature, blood oxygen levels, sugar levels and hydration, it is vital for the body to maintain homeostasis. Without exercise the body maintains homeostasis by eating and drinking correctly. However, during exercise the body needs to have a constant supply of oxygen to the cells to support the moving muscles, “During exercise, your body needs to maintain a constant supply of oxygen in your cells to support your working muscles, which might need 15 to 25 times more oxygen than when they are resting” (Fisk, 2015). Due to this, the breathing rate increases, and keeps increasing the harder the body is being pushed.

Good physical health is a vital part of the well-being of every person. A major component of our physical health is “Cardiovascular fitness”. Cardiovascular fitness is the ability of the heart and lungs to provide oxygen to the muscles for activity of an extended duration. If we have a good level of cardio-vascular fitness we are able to sustain activity for a reasonable period of time and not fatigue easily. This can give individuals a variety of health benefits and allow more regular and enjoyable activity to be participated in. This research report will examine my results of cardio-vascular fitness tests and weekly physical activity events, which

The controlled variable included the exercise bike and heart rate monitor. There are several limitations, systematic and random errors that should be considered when interpreting these results. (4) The controlled variables were not tested before this experiment to see if they were working and reliable. Figure 2 heart rate was quite inconsistent and did not follow the pattern of the other results, which maybe suggest a random error with the heat rate monitor. A systematic error could include the fitness of the participants. One of the test subjects is an endurance athlete and the other does not compete in any sport. This would affect the results because for the endurance-trained athlete, from their training they increase their cardiac output results from a substantial increase in maximal stroke volume. In untrained persons, cardiac output increases in response to exercise primarily by an increase in heart rate. The endurance-trained athlete does so mainly by an increase in stroke volume. Simply meaning that although both participants are doing the same cadence and length the endurance athletes skewers the results by already having an increased rate in stroke volume. Another systematic error may include the rate of perceived effort. For the most accurate results, the measured maximum heart rate would be necessary to give an accurate cadence to ride at.

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).