Cellular Respiration

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.

Brooks GA, Fahey TD, Baldwin KM (2005). Exercise Physiology: Human Bioenergetics and Its Application. 4th Edition

As stated before the three energy systems used by the body are the ATP-PC, anaerobic glycolysis and aerobic system. The ATP-PC and anaerobic glycolysis system (also known as lactic acid system) are anaerobicly based meaning that they don’t need a sufficient amount of oxygen to produce ATP. The aerobic system requires oxygen to produce ATP hence its name. All three system have fuels’ which produce energy. The ATP-PC uses phoso creatine and creatine phosphate, the lactic acid system uses glycogen and the aerobic system uses glycogen and triglycerides . Glycolysis refers to the breaking down of glycogen to from glucose which is used in ATP.

Your body requires energy in order to be able to perform tasks. Energy comes in many different forms. They are chemical, light, sound, heat and mechanical. You can get energy from different food substances i.e. glucose, fatty acids, sugars and amino acids. To be able to get the energy from these food substances energy needs to be released with oxygen. This is known as aerobic respiration. The role that energy plays in our body is the process of moving molecules in and out of our cells while breaking down the larger molecules and building new molecules. The cardiovascular system transports oxygenated blood around the body and to the cells. It will then collect the deoxygenated blood which is ready for the excretion from the cells. The cardiovascular system will deliver the nutrients oxygen and glucose via the blood stream. Oxygen is need for aerobic respiration to occur. The cardiovascular system will pump oxygen and nutrients carrying blood throughout the body. The glucose molecules that are carried by the blood are transported into the cells. Along with the oxygen that is diffused into the cells they are used in respiration to produce ATP. The respiratory system is responsible for bringing in oxygen as well as using it to burn the nutrients that we need for energy. The respiratory system contains alveoli which allow the diffusion of oxygen into the blood stream

Metabolism comprises of a vital set of biochemical reactions that all living organisms require to sustain life. For a marathon runner, their physiological response to strenuous exercise depletes both their fats and carbohydrate storage in order to supply energy in the form of Adenosine Triphosphate (ATP). ATP is the energy form that the human body uses for biological processes such as movement and synthesis of biomacromolecules. In regards to running a marathon, the athlete is capable of using a combination of both anaerobic and aerobic pathways, but these different systems predominate at different intervals in order to increase the energy allowed for the muscles.

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).

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.

However, if intense physical demands such as cycling, swimming or running are placed on the body, the systems respond by producing much higher levels of ATP to ensure that our immediate energy needs are met. When doing these exercises ATP then becomes ADP, as there is a loss in the phosphate molecules. The body has two main energy systems, the aerobic energy system which utilises fats, carbohydrate and sometimes proteins for re-synthesising ATP for energy use.

The energy system that is able to generate ATP without oxygen is called the anaerobic system. Anaerobic meaning without oxygen. This system is formed from the combination of ATP and lactic acid. The metabolic pathway of the anaerobic system is called anaerobic glycolysis. Glucose is broken down during the metabolic pathway glycolysis, with or without oxygen present. Carbohydrates are the only macronutrient that can be catabolized during glycolysis.

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

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.

The Three Energy Systems The Anaerobic Energy System The term ‘anaerobic’ means ‘without oxygen’, however this does not mean that you should hold your breath whilst participating in activity. It means that at that point in time when the energy being used is created, there is an insufficient amount of oxygen present, and this is generally because the short duration of the activity doesn’t allow the body to create enough oxygen. Anaerobic energy production occurs during activities that last less than 90 seconds and require power, such as sprinting and weight lifting.

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.

Physical fitness has two main classifications-performance related and health related. People have different performance related requirements in accordance with their occupation but all people have the same health related requirements (The World). Then there are two types of exercise that helps tone a person’s body while increasing its endurance. These are aerobic and anaerobic. Aerobic exercise is exercise that uses the muscles and bones. Cardio activities are a good example of this, such as running or biking. This type of exercise increases the strength of a person’s heart and boosts their lung capacity. Anaerobic exercise is an intense but short amount of exercise (Payment). Since it is only for a brief amount of time, it does not require the amount of oxygen aerobic exercise does. Instead it uses glycogen which comes from the sugar in a person’s blood. An example of this exercise is weight lifting or sprinting. A person’s requires both anaerobic and aerobic exercise for good health. Simply doing a cardio work out is not healthy, and for a person to see real results there must be some activity like weight lifting (“Anaerobic”).