A Biological Description on the Correlations Between Heart Rate, Respiration and Physical Exercising

THE EFFECT OF EXERCISE ON HEART RATE AND RESPIRATION RATE

Introduction

Homeostasis is a term that is used to describe the survival of organisms within an ecosystem and to describe the survival of cells inside an individual organism. When discussing the inner workings of an organism homeostasis describes an environment that supports the survival of cells. All of your body systems work together to maintain homeostasis inside your body. Homeostasis is achieved by making sure temperature, pH, oxygen, glucose, hormones and many other factors are just right for your cells to survive. It is important that these homeostatic levels will be different for different species and may even be slightly different within a species.

One method of homeostatic control that the human body uses are called negative feedback loops. These are the more common of the two, the alternate being a positive feedback loop. In a negative feedback loop, there is a change to the internal or external conditions, a detection by receptor, and an effector to return the levels to normal. It is a corrective mechanism to return back to the optimal conditions.

The circulatory system, comprised of the heart and all associated vessels, ensures that oxygen and nutrients are being delivered to all cells in the body, and is also responsible for the removal of waste, such as carbon dioxide. Resting heart rate in a human is approximately 60-70 beats per minute however, this can change depending on the needs of the body, tissues and muscles.

The respiratory system consists of the mouth, nose, trachea, lungs and associated muscles. This system is responsible for breathing. Within the alveoli of the lungs, the oxygen from the air we breathe in is diffused into the capillaries and blood surrounding the alveoli sac. At the same time, the carbon dioxide from the blood is diffused into the alveoli and we breathe it out. The two systems are very closely related as the respiratory system and circulatory system need to match each other. For examples, if the tissues require more oxygen, the heart pumps faster and breathing rate increases to ensure there is sufficient oxygen for the tissues.

Variables

Independent Variable: In this experiment the exercise intensity of 4 subjects will be changed. One subject will be at rest, one will exercise mildly by walking on a treadmill, one subject will exercise moderately by jogging on a treadmill, and one subject will exercise intensely by sprinting on a treadmill.

Dependent Variable: The heart rate and breathing rate of the subjects will be tested. They will be wearing watches that monitor their heart rate, and someone will count the number of breaths they take in the minute immediately after they finish exercising.

Controlled Variables: In this investigation the things that will kept same is the time they exercise, the treadmill, the environment in which they exercise and the person doing the exercise.

Research Question

Is there a relationship between the intensity of exercise and the breathing and respiratory rate of person?

Method

1. The first subject wore the device that would monitor heart rate.
2. The subject stood on the treadmill but did not move or walk.
3. A timer was started for 5 minutes.
4. At the end of the 5 minutes the number of breaths taken by the subject was recorded.
5. The heart rate data was taken from the device and recorded.
6. The second subject wore the device that would monitor heart rate.
7. The timer was started and the subject walked on the treadmill at a speed 5km/h.
8. At the end of the 5 minutes the number of breaths taken by the subject was recorded.
9. The heart rate was taken from the device and recorded.
10. Steps 6 to 9 were repeated for moderate exercise, at 10km/h, and intense exercise, at 16km/h.

Results Collection

Heart Rate (beats/minute)

Subject 1 Subject 2 Subject 3 Subject 4

1 minute 76 79 80 80

2 minute 75 82 84 88

3 minute 75 85 85 94

4 minute 77 85 170 102

5 minute 76 83 95 110

Breathing Rate (beats/minute)

Subject 1 Subject 2 Subject 3 Subject 4

End of Trial 15 15 22 36

Graphs

Discussion

Interpret the results, are there any patterns or trends?

Throughout this experiment there were various patterns and trends. Looking at the graphs it is visible that an increase in exercise intensity leads to a faster heart rate and breathing rate. The first subject stood on the treadmill but did not walk or move therefore the heart rate was constant. Subject 2 walked on the treadmill at 5km/h, hence the heart rate started with 79 beats/minute and ended with 83 beats/minute. However, both first and second subjects had a breathing rate of 15 breaths/minute at the end of the trial. Subject 3 exercised at 10km/h with a heart rate of 80 beats/minute, a sudden increase can be seen on the graph at four minute, by five minutes the heart rate was 95 beats/minute with a breathing rate of 22 breaths/minute. Finally, subject 4 exercised intensely at 16km/h and had a heart rate of 110 beats/minute at 5 minutes. The breathing rate was 36 breaths/minute.

Analyse the data. Use scientific concepts to explain patterns, trends or relationships identified in the data. Use specific points from the results in your answer to support your statements.

As per the results it is obvious that the heart rate and breathing rate increased due to the high intensity of the exercise. This can be connected scientifically. As a person is exercising at a higher intensity more oxygen is needed in the body to be used, this also means a lot of waste is also being removed from the body. The heart rate was increasing as the body was pumping more oxygen into the legs, giving the legs more energy to do the exercise. The person’s breathing rate also increases so that they can inhale more oxygen and exhale more carbon dioxide. The respiratory system and the circulatory system worked together to produce more oxygen for the body to be pumped out to the legs to produce energy for the legs to maintain the exercise the whole way. Though the first two subjects had only a slight increase of 1 or 2 beats/minute, this highlights that the person isn’t exercising or they are very fit, hence their heart doesn’t have a huge increase. Subjects 3 and 4 clearly shows the higher the intensity the higher the heart rate and breathing rate is.

Are they any errors (such as sample size, sample selection, measurement control, poor variable control)? What is the significance of each of these?

They were many significant errors throughout the experiment. In the first table of data, subject three’s heart rate goes from 80, to 84, to 85, to 170 and back down to 95. The 170 is a major outlier, this is an evident mistake. This could have been a simple mistake made by the recorder or the heart rate monitor might have had a slight error. The research question was also includes an error as they compare the breathing rate and respiratory rate. This is the same thing, it should have been heart rate and respiratory rate. Also the results had beats/minute for breathing rate instead of breaths/minute.

Conclusion

Evaluate the design of the experiment. Was the experiment reliable and valid? Is this a fair test, consider the use of the experiments variables? Would the results be replicated if someone else followed the method exactly?

The experiment was done well however there are few things that would have helped to be a fair test. The ‘subjects’ (people being tested) could have been stated. Results can vary by the person doing the exercise. For example, if an obese person was doing the exercise, the heart rate and breathing rate would have been different, it could have been higher. However, if a fit person was doing the exercise, the breathing and heart rate might have been lower. This is a major variable that should have been kept same and a change to this would have helped to be a fair test. The method is clearly stated but as indicated before, informing the audience the type of person doing the test would have made it easier.

How could the design of the experiment have been improved to reduce error and increase fairness and accuracy so that the results are higher quality for next time? Explain how they will improve the experimental design.

This experiment could have been done better to reduce error and increase fairness and accuracy by stating the type of person doing the experiment. This is a huge variable and should be kept the same however, in this experiment there was no statement on the gender or type of person. In addition, instead of having four people doing the exercise there should have been one. This would help to make this a higher quality for next time. Making one person do all four different intensity levels would have made it more accurate as they should have the same heart rate and breathing rate and could have been easily compared. Furthermore, the experiment only held 1 trial, ideally it would have been better if it was 3 trials. This would increase the accuracy of the experiment.

In the experiment and results, the research question has been answered. Looking at the data, it has been determined that in this experiment an increase in exercise intensity will lead to a faster heart rate. It was also shown that increasing in exercise intensity will lead to more breaths per minute taken.