Both the respiratory and circulatory systems play vital roles in order for our body to function. Their individual way of responding to exercise was examined whilst conducting the multistage fitness test in the lab.
The respiratory system is a vital system in our body which takes in oxygen and removes carbon dioxide. For an organism to live and survive each cell within their body needs the supply of oxygen (O2) and energy obtained from food as well as carbon dioxide to exit their body as oxygen enters. These jobs are all responsibilities of the respiratory system.
The process that the respiratory system endures is known as respiration. The respiratory system is made up of the nose, mouth, pharynx, larynx, trachea, bronchi and lungs.
Oxygen in the air is breathed in via the nose or mouth called inspiration caused by the diaphragm contracting. The oxygen passes through the nasal passages transporting the air to the pharynx. The pharynx acts as a pathway to the larynx. White blood cells in the larynx complete their role by attacking potentially diseases causing microbes from travelling any further if they have already passed the other defensive forces in the nasal pathways.
The larynx role in the respiratory system is to transport air to the trachea. Strong rings of cartilage enable the trachea to open so that air can pass through this passageway from the larynx to the bronchi. The bronchi separates into two tubes from the trachea which also split into more tubes known as the bronchioles. Air sacs called alveoli then transport oxygen whilst removing carbon dioxide. From here the oxygen scatters into our capillaries then to vessels which connect the arteries and the veins. Pulmonary veins carry blood to the left atrium of the heart, flowing to the left ventricle. The blood is then pumped to the rest of the body through the arteries and the oxygen is now lost. Haemoglobin in red blood cells also transports oxygen to cells in the body. The blood returns to the heart by the pulmonary veins through the right atrium and ventricle. The deoxygenated blood is now returned to the lungs and the exhalation occurs and this air is breathed out through the nose and mouth.
When oxygen cannot be supplied to the muscles quick enough oxygen from the haemoglobin, myoglobin air in the lungs, and body fluids acts as a temporary substitute until the oxygen flow can regain itself when the borrowed oxygen is returned to wherever it may be borrowed from. This is called oxygen debt.
Blood is continually flowing around our bodies. The bodily parts which the blood flows through make up the circulatory system or alternatively the cardiovascular system. The circulatory system includes the heart, blood and blood vessels.
This system pumps blood containing oxygen and nutrients around the body and collects wastes. The heart is what enables the blood to be pumped around the body. It is situated between the lungs and diaphragm with a muscle wall dividing it into a left and right side. There are two chambers in each side being the atrium and ventricle. Haemoglobin in red blood cells absorbs oxygen and carries it to body cells. Cardiac blood vessels linked from the aorta spread over the myocardium which is a special muscle that these chambers are made up of and allows the heart to pump blood, along with the cardiac cycle.
The cardiac cycle is the process that the heart goes through to contract and relax to receive blood from the veins and pump it to the lungs and around the body. The cardiac process can be described in a two step process. Diastole is when the heart expands and blood flows from the atria into ventricles. Systole is when the heart contracts and deoxygenated blood flows into the arteries form the ventricles and to the lungs and body. Our heart rhythmically contracts requiring a rich supply of blood and oxygen to do this.
The cardio-respiratory system played a vital role in order for me to complete the beep test. Prior to the test both the respiratory and circulatory systems and the co-functioning of these making up the cardiovascular system were all at rest. They were functioning as normal because no extra stress was placed upon the heart. For example; my resting heart rate was measured at 60 beats and my respiration at 16 breaths. Both my heart rate and respiration rate however was evidently affected by exercise as was both of these bodily systems.
I do not think that my demand for oxygen was increased prior to the commencement of the test because I really wasn’t nervous or anticipant which for other people may have led to their heart rate to increase even before the physical aspects of the test had begun.
During the test my respiratory activity increased to facilitate for my demand of increased oxygen consumption. Greater volumes of air were being consumed during the test. For example; I reached level 10, shuttle 2 in the test. My breathing rate had more than doubled over the intercourse of the test. The total output by the heart known as cardiac output also increased during the test and may have reached up to 25 litres per minute.
During the test, the supply of oxygen was increased so that my muscles could continue working. While the test was occurring a greater demand was placed on the heart to pump and circulate blood around the body and to the muscles quicker. My oxygen uptake increased due to the physical demands of the test. Oxygen uptake is how much oxygen my muscles were able to take up when working in conjunction with one another. For example; my VO2 immediately after the test was 47 millilitres per minute on average in comparison to 3.5 millilitres when at rest. Gaseous exchange also occurred during the test. As I inhaled oxygen through the lungs eventuating into the blood, the capillaries then had a greater concentration of carbon dioxide rather than oxygen and diffusion to the alveoli allowed me to breathe out this carbon dioxide.
The greater demand for oxygen is also exemplified by the fact that my results showed that my breathing rate increased up to 182 beats per minute in comparison to 60 which was my resting heart rate (diagram 1). Not only were changes occurring to the circulatory and respiratory systems at the start and end of the test however throughout the test my body was adapting to the exercise as intensity increased.
Although my heart rate and respiration rates were not recorded midway of the test, I could notice that both were gradually increases. For example when I was out of breath, my respiratory system had performed to the maximum of its potential. Whilst completing the test my systolic pressure, cardiac output and stroke volume also increased to meet the demands that my body had placed on these systems. For example; the muscles became responsible for up to 85-90 per cent of the cardiac output whereas at rest the other tissues took on this role.
Our circulatory and respiratory systems’ working together is what enabled my performance in the beep test. Whilst the blood flowing to my lungs was increased by the functioning of the circulatory system, my respiratory system made it possible for a greater volume of air to flow into my lungs through inspiration and expiration to meet the demand of oxygen that was required for my body to perform this task
*Graph displaying that exercise rapidly increased heart rate and respiration rates after five minutes of recovery heart rate was the same as it was prior to commencing the test.
The stress that had been previously placed on the heart was reducing when the test finished. The body was no longer exercising thus when exercise is over, the heart rate drops quickly and then gradually returns to the resting heart rate. Carbon dioxide levels are reduced during the recovery period and oxygen levels are increased. For example; the following table demonstrates how after minute intervals my heart rate continued to decrease and after 5 minutes both my respiration and heart rates were already back to my reasting rates
*The changes of the respiration and heart rates over the duration of the test particularly recovery
As can be seen the ability and efficiency of the cardio-respiratory system is vital when participating in exercise and testing methods such as the beep test can be used to effectively test this.
3. Evaluate your own level of cardio-respiratory fitness with specific reference to their recorded respiration rates, heart rates, level of achievement in the beep test and norms. (10 marks)
In the beep test I achieved level 10 shuttle 2. On the day I wasn’t all that motivated and my performance wasn’t as competent as previous attempts I have had at completing the beep test. My motivation, surface and time of day were all relevant contributing factors that I believe may have affected my performance and possibly not given a true indication of my cardio-respiratory fitness. However according to my results my level of shuttle was in the very good range in comparison to the norms (displayed in the table below).
*Graph displaying the Norms for the Beep Test
Achieving a high result in the beep test can be an indication that I have a high level of cardio-respiratory fitness which is why I am capable of completing this test and scoring highly in consideration with the norms.
My average resting heart rate was 60 beats per minute. Heart rate can be affected by fitness levels, age, gender and other variables. The normal heart rate is around 70 beats per minute when at rest however this increases for children. When comparing my heart rate to the norms prior to beginning the test, my resting heart rate is much lower than the norms showing that my body and muscles have a lower demand for oxygen than the ‘average’ person when physical activity is not a contributing factor. My heart rate rapidly increased over the test and my heart rate immediately after the test was 182 beats per minute. The normal number of beats per minute is 180-200. As I was in the lower range of this norm again reflects my resting heart rate which was also lower and shows that my previous experience in training specified for cardio-respiratory fitness was beneficial for me to perform this task. My resting heart rate also shows that my anticipation was controlled and didn’t impact my heart rate to increase before commencing the test.
Training for a specific purpose for example; to improve cardiorespiratory endurance will assist to improve the result of this test. I do regularly train in this style and my preferred form of exercise is of long duration and a gradual build up of intensity which is exactly what the beep test requires. Once your body is trained in a particular way for a lengthy period of time then the systems within it become accustomed to work at that pace. For example- If I were to complete the beep test each week in the same conditions however increased training between testing then I would significantly notice an increase in my result, as well as decreased heart rate and respiratory rates in comparison to this testing because my cardio-respiratory system would become familiar with having this demand placed upon them.
My respiration rate prior to the test was 16 and immediately after the test were 36 breaths. After completing the beep test I was very out of breath and the feeling of exhaustion embodied upon me. The circulatory and respiratory systems roles as described in question 2, had to work at a much faster pace to supply oxygen to the heart and pump blood around the body and the muscles so that the too could work effectively thus why my breathes rapidly increased to try to facilitate and consume as much oxygen and replace the oxygen from the process of oxygen debt.
Non Athletes
My relative VO2 max is 47.4 ml/kg/min and this categorised me into the very good range. The norms for relative VO2 for people ages 10-19 years is 38-46 ml/kg/min. These results display that I am able to take up a greater amount of oxygen to my muscles than the average female in the 10-19 year old age group. My absolute VO2 max is 3.0 L/min which categorised me in the excellent range.
In conclusion I have an overall excellent individual level of cardio-respiratory fitness. My results indicate that when compared to the norms for my respiration rate, heart rates and level of achievement I am well above average and in the top category for each of these. This means that my respiratory and circulatory system work efficiently and partake their roles both as independent systems and when working together.
Bibliography
Websites
Books:
Ruskin Ron.(2000) Outcomes 1: PDHPE preliminary course. John Wiley and Sons Australia Ltd, QLD
Various authors. “Physical Activity in Australia: A Snapshot”. Australian Bureau of Statistics.2004-05; 4835.0.55.001.
Ruskin Ron.(2000) Outcomes 1: PDHPE preliminary course. John Wiley and Sons Australia Ltd, QLD
Assignment cover sheet pg4