Sports Science Coursework General Aim: Investigate the reasons for fitness levels of individuals in relation to weight and number of minutes of physical activity undertaken per week. Research Question: Is there a greater relationship between the weight of an athlete and their fitness levels, or the number of minutes of physical activity they do per week and fitness levels? Hypothesis: There will be a greater relationship between the number of minutes of physical activity individuals do per week and fitness levels than weight and fitness levels. Background Information Many coaches and trainers use the Multi- Stage Fitness (Bleep test) test in order to find out the approximate VO2 max of an athlete. For this experiment I will be using the bleep test as a measure of students fitness levels in order to determine whether there is a relationship between the mass of an individual and their fitness levels, whether there is a relationship between the number of minutes of physical activity per week an individual takes and fitness levels, and which is greater. The test involves each student running 20m shuttles before the bleep sounds on the recorded CD. The time between the bleeps gradually decreases, forcing the individual to run faster. I will be measuring the fitness of the students by recording the amount of times they can run the 20m shuttles in time with the beep. Normally, the bleep test is measured in levels. Within each level, there are a certain number of bleeps that have to be achieved in order for it to be completed. This number increases throughout the test. Rather than measuring the test in levels, in order to improve accuracy, I will be measuring the test in the number of bleeps completed before the individual fails to complete a shuttle. The conversion from levels to number of shuttles completed can be found in the appendix. The individuals tested will be of similar gender, age and sporting ability in order to make the test valid. The longer and further the individuals can run, the greater their fitness level. Independent Variables The independent variable for my investigation will be the weight (kg) of the individuals being tested as well as the number of minutes of physical activity that they do per week. Dependant Variable The dependant variable will be the number of shuttles completed whilst undertaking the bleep test. Sports, exercise and health science teacher support material 1
Controlled Variables Distance Running Surface Clothing Activity undertaken before test Age Gender Sample Test conductor Bleep test Scales How to Control the Variables Distance- I will use the same tape measure and same area to do the tests in order to make sure the 20m distance remains constant throughout. Running surface- Similarly, I will make sure that the surface I use to carry the tests out on is the same. i.e. I will use the same sports hall for each student tested. Clothing- the students tested will be in PE kit in order to make sure the test is fair and that students results are not affected by their clothing. Activity undertaken before Test- The students will be on lunch prior to the test and would have therefore not undertaken any activity prior to the test. Age- All of the students that I am testing will be between the ages of 13 and 14 because they are all in grade 8. Gender- There will be no discrepancy as a result of students of different gender being tested, as they are all female. Sample- The sample is the Set 1 Grade 8 PE class, which means they are all of a similar skill level for sport in general. Test Conductor- In order to ensure all of the tests are carried out in the same way, I will be the only test conductor plus one other assistant to help to monitor the other end of the sports hall, and collect other data as I cannot do both. Bleep Test- the students will all be using the bleep test CD with the bleep test on it, and also all students will be conducting the test at the same time. Scales- Each student will be measured in kilograms and the same scales will be used. The recorder will record the students weight on a piece of paper and pass the paper to the second recorder to avoid any embarrassment for the individual over their weight. Sports, exercise and health science teacher support material 2
Table of apparatus Name Number Size/ concentration Error Margin (+/-) 20m running 1 20m space 0.5m surface Tape Measure 1 20.0m 0.5cm Bleep Test CD 1 1 - Scales 1 1 0.05kg Cones 4 20 - CD Player 1 1 - Method 1. Measure each students weight in kilograms on the same set of scales. 2. Test conductor will measure weight of each student, write it down and pass it to assistant conductor to be recorded. This will avoid embarrassment over weight issues. 3. Measure each student s height in cm using the same measuring stick. 4. Test conductor will measure height, write it down and pass it to assistant conductor to be recorded. This ensures data that is collected for height is collected in the same way as data collected for weights. 5. Mark the starting line with 10 cones the same distance apart, parallel to one another. 6. Mark the finish line 20m from the start line with 10 cones the same distance apart, directly opposite the cones on the start line. 7. The conductor will ask for the students to divide into two groups of what they perceive to be similar paces. 8. Conductor will explain the aim of the investigation and the way in which it will be carried out (see background information). 9. The bleep test CD starts with a five second countdown and students must continually run 20m shuttles in time with the bleep ensuring that either foot touches the line, either at the sound of the bleep, or before it. 10. If students do not reach the line before or at the sound of the bleep then they have one more chance to make the bleep. If they fail to do this then they must stop performing the test and then number of bleeps that sounded before this point will be recorded. 11. The conductor must ask students to stop to ensure that the test is valid and fair. Sports, exercise and health science teacher support material 3
12. While the first twelve students are running the bleep test, the other twelve students will be watching one other student each and counting the number of bleeps achieved. 13. When their partner stops or fails to reach the line before the bleep twice, their score is recorded. 14. Once the first twelve students have completed the test, the second twelve students will carry out the test in the same way. Sports, exercise and health science teacher support material 4
Data Collection and Presenting -Raw Data Table (1) to show the weight, height, number of bleeps achieved in the bleep test and the number of minutes of physical activity individuals undertake per week. Name Weight (kg) +/- 0.05 kg Height (cm) +/- 0.05cm Bleeps Achieved Minutes of physical activity per week (minutes) +/- 0.5 minutes 1 48.1 162 59 550 2 43.1 158 88 485 3 46.7 169 64 490 4 44.3 160 75 610 5 54.3 163 75 580 6 42.8 155 72 500 7 45.5 164 93 550 8 46.5 158 87 520 9 66.2 169 32 490 10 62.9 160 50 160 11 47.4 156 53 220 12 50.0 162 75 300 13 46.0 156 66 250 14 56.1 157 54 160 15 49.7 157 79 700 16 54.5 169 81 1080 17 40.6 159 111 620 18 49.1 157 73 940 19 67.1 169 65 640 20 57.8 167 73 580 21 55.0 163 62 540 22 49.7 167 93 550 23 46.2 156 62 700 24 43.6 160 101 610 Sports, exercise and health science teacher support material 5
Data Processing and Presenting Table (2) to show the weights, number of bleeps achieved, and number of minutes of physical activity done per week of individuals. Processed Data Anomalies Individuals Weight (kg) +/- 0.05 kg Bleeps Achieved Minutes of physical activity per week (minutes) +/- 0.5 minutes 1 48.1 59 550 2 43.1 88 485 3 46.7 64 490 4 44.3 75 610 5 54.3 75 580 6 42.8 72 500 7 45.5 93 550 8 46.5 87 520 9 66.2 32 490 10 62.9 50 160 11 47.4 53 220 12 50.0 75 300 13 46.0 66 250 14 56.1 54 160 15 49.7 79 700 16 54.5 81 1080 17 40.6 111 620 18 49.1 73 940 19 67.1 65 640 20 57.8 73 580 21 55.0 62 540 22 49.7 93 550 23 46.2 62 700 24 43.6 101 610 Sports, exercise and health science teacher support material 6
A graph to show relationship between number of minutes of physical activity done per week and number of bleeps achieved (fitness levels) Graph Physical Activity per week (minutes) 1 X axes- Bleeps achieved (fitness levels) Here we can see visually from Graph 1 that there is a moderate positive correlation between number of minutes of physical activity done per week and fitness levels. In order to improve my investigation I am going to test for outliers, which may be affecting the accuracy of my investigation. This will allow me to get a better visual representation of the data. This can be seen below. Data and outliers for number of bleeps achieved Minimum (Min)- 32 Lower Quartile (LQ)- 62 Median (Med)- 73 Upper Quartile (UQ)- 81 Maximum (Max)- 113 IQR( = UQ- LQ)= 19 The numbers above will help me find the outliers, which are shown and calculated below: Outliers for upper boundary= UQ + 1.5 x IQR Outliers for upper boundary= 81 + 1.5 x 19 Outliers for upper boundary > 109.5 Sports, exercise and health science teacher support material 7
Outliers for lower boundary= LQ 1.5 x IQR Outliers for lower boundary = 62 1.5 x 19 Outliers for lower boundary < 33.5 Total outliers for bleep test= 32 and 111. These can be seen in table 2. Data and outliers for Number of minutes of physical activity per week Minimum- 160 Lower Quartile- 485 Median- 550 Upper Quartile- 610 Maximum- 1080 IQR= 595 The numbers above will help me find the outliers, which are shown and calculated below: Outliers for upper boundary= UQ + 1.5 x IQR Outliers for upper boundary= 610 + 1.5 x 595 Outliers for upper boundary > 1502.5 Outliers for lower boundary= LQ 1.5 x IQR Outliers for lower boundary= 485 1.5 x 595 Outliers for lower boundary < - 407.5 No outliers for number of minutes of physical activity per week. Now I have found the outliers for the data, which I am using in order to determine the strength of the relationship between number of minutes of physical activity done per week and fitness. The data can now be demonstrated in the graph below without outliers. Sports, exercise and health science teacher support material 8
Graph to show relationship between number of minutes of physical activity done per week and number of bleep achieved (fitness levels) without outliers. Graph 2 Physical Activity per week (minutes) Bleeps achieved (fitness levels) By looking at graph 2, we can see that there is certainly some correlation between the two variables. This has been made more clear by extracting the outliers from the data. By calculating the correlation coefficient (once again excluding outliers), we can tell exactly how strong the correlation is between the data which demonstrates the relationship between number of minutes of physical activity done per week and number of bleeps achieved (fitness levels). We calculate the correlation coefficient by finding: When calculated, the correlation coefficient between the number of minutes of physical activity per week and the number of bleeps achieved is: 0.4331467966 From this we can see that there is moderate positive correlation between number of minutes of physical activity per week and number of bleeps achieved. It is now necessary for us to demonstrate the relationship between weight and fitness levels in order to determine whether the correlation between fitness levels and number of minutes of sport done per week is stronger or weaker than the correlation between weight and fitness levels. Sports, exercise and health science teacher support material 9
Graph to show relationship between weight and number of bleeps achieved (fitness levels). Graph3 Weight (kg) Bleeps achieved (fitness levels) Here we can see visually from graph 3 that there is a moderate negative correlation between weight and fitness levels. We have already determined that the outliers for the number of bleeps achieved are 32 and 111. Once again, I will be excluding these from my data in order to maintain the consistency throughout my investigation and also to increase the accuracy. However I also need to calculate the outliers for the weight of the individuals. Data for Weight of individuals Minimum (Min)- 40.6 Lower Quartile (LQ)- 45.5 Median (Med)- 48.6 Upper Quartile (UQ)- 54.5 Maximum (Min)- 67.1 IQR= 9 The numbers above will help me find the outliers, which are shown and calculated below: Sports, exercise and health science teacher support material 10
Outliers for upper boundary= UQ + 1.5 x IQR Outliers for upper boundary= 54.5 + 1.5 x 9 Outliers for upper boundary > 68 Outliers for lower boundary= LQ 1.5 x IQR Outliers for lower boundary= 45.5 1.5 x 9 Outliers for lower boundary < 32 No outliers for weight of individuals. There are no outliers for the weight of the individuals but there are outliers for the number of bleeps achieved. Therefore, it is still necessary for me to demonstrate the data in a graph without the outliers from the bleep test. Graph to show relationship between weight and number of bleeps achieved (fitness levels) without outliers. Graph 4 Weight (kg) Bleeps achieved (fitness levels) Once again, we can see visually from Graph 4 that there is again a moderate (but this time negative) correlation here between the weight of individuals and their fitness levels. This has been made clearer due to the fact that the outliers from the bleep test have been excluded. We must once again use the correlation coefficient in order to determine just how strong the correlation is, and whether or not it is stronger or weaker than the correlation between number of minutes of sport done per week and fitness levels. The correlation coefficient is calculated by: Sports, exercise and health science teacher support material 11
The correlation coefficient between the weight of individuals and the number of bleeps they achieved (fitness levels) is: -0.4323919672 From this we can once again see that there is a relatively weak negative correlation coefficient between weight of individuals and the number of bleeps they achieved. Conclusion In conclusion, as we have seen from the correlation coefficients of the two separate sets of data, the relationship between weight and fitness levels (measured by the bleep test) and number of minutes of physical activity per week and fitness levels, is very similar. The fact that the correlation between weight and fitness levels is negative is irrelevant due to the fact that we are only investigating the strength of the relationship between fitness and number of minutes of physical activity done per week and fitness and weight. Therefore, the hypothesis was incorrect due to the fact that there was not a greater correlation between number of minutes of physical activity done per week and fitness levels than between weight and fitness levels. If I was to investigate this further, I may also have looked into whether there is a relationship between height and fitness levels and could also have looked at whether the specific sport that you play also affects fitness levels. Evaluation The table below shows weaknesses and limitations to the experiment as well as improvements that could be made. Problems During the bleep test, there were only two test conductors and it was therefore very difficult for us to monitor all thirteen children at once and to make sure they all reached the line each time. One significant limitation was that during my investigation, I did not have two lines, which were twenty metres apart between which the students could run the shuttles. Instead I had to use one line as the start line and a line of cones as the finish line. Using cones created the possibility for human error due to the fact that it was very difficult to line them up perfectly straight. It was also more difficult to judge whether or not the students had Solutions In the future, I would also ask a number of my class mates to help me conduct the test due to the fact that this would make it easier to monitor each child in the bleep test, making sure that they all touched each line every time. Finding two lines, which are twenty metres apart is quite difficult. Therefore, if I were to do the investigation again, I would use tape instead of cones to represent the start and finish lines. This would make the investigation more accurate due to the fact that it would be easier for the test conductor to see whether or not the students make it to the line. Sports, exercise and health science teacher support material 12
touched the line or whether they had fallen short of it due to the fact that I had to draw an imaginary line between the cones and judge it myself. Therefore the accuracy of the investigation was reduced. When carrying out the investigation, there was not enough room in the sports hall for all twenty four students to do the bleep test at once, they had to be split into two groups. This may have affected the accuracy of the investigation as different levels of motivation and competitiveness may have affected the results. The age of the students being tested may also have caused inaccuracies. This is due to the fact that when measuring weight, the student s physical maturity is not taken into account and this may also affect their fitness levels. The way in which the investigation was carried out, meant that as one student ran, another was counting how many bleeps their partner achieved. The accuracy of this investigation may have been limited by the fact that I only carried out the bleep test once. This may have reduced the reliability of the test. One final problem that was encountered was the fact that the students carried out the test having just finished their lunch. This meant I Finding a larger area in which to carry out the investigation could have solved this problem. This way, students would not have benefitted from the extra rest before doing the test, or from watching other students doing it which may have improved their knowledge of the test and consequent ability to carry it out better. Testing adults or students who have finished physically maturing may have increased the accuracy of the investigation and could therefore have solved this problem. This did not cause any inaccuracies but in future and in order to guarantee complete accuracy of the investigation, I would have the students ticking off each bleep that their partner achieved on a previously made sheet. The test could have been done more times (for example 3 in total) and taken the average number of bleeps. This would have increased the accuracy of the fitness levels of each individual. I considered doing this, however, I was carrying out the test during the students class time and therefore could not take up more time within their curriculum than necessary. A possible solution to this may have been to carry out the test over a period of 12 or more weeks, which would have been less disruptive to the curriculum and would have allowed me to test the students more than once. The most suitable way of solving this problem would have been to carry out the test after lunch, which would hereby have meant that students Sports, exercise and health science teacher support material 13
could not have controlled what they ate, meaning that energy intake would have been different for different students. Also it may have been more difficult for all of the students to achieve a good result if they had just eaten. would not feel full, and energy intake of the students would have been more similar. Sports, exercise and health science teacher support material 14
Appendix The Bleep Test Level Shuttles Speed (km/h) Secon ds per shuttle Total level time Dista nce (m) Cumulative Distance (m) 1 7 8.5 8.47 59.29 140 140 2 8 9 8 64 160 300 3 8 9.5 7.58 60.64 160 460 4 9 10 7.2 64.8 180 640 5 9 10.5 6.86 61.74 180 820 6 10 11 6.55 65.5 200 1020 7 10 11.5 6.26 62.6 200 1220 8 11 12 6 66 220 1440 9 11 12.5 5.76 63.36 220 1660 10 11 13 5.54 60.94 220 1880 11 12 13.5 5.33 63.96 240 2120 12 12 14 5.14 61.68 240 2360 13 13 14.5 4.97 64.61 260 2620 Sports, exercise and health science teacher support material 15
14 13 15 4.8 62.4 260 2880 15 13 15.5 4.65 60.45 260 3140 16 14 16 4.5 63 280 3420 17 14 16.5 4.36 61.04 280 3700 18 15 17 4.24 63.6 300 4000 19 15 17.5 4.11 61.65 300 4300 20 16 18 4 64 320 4620 21 16 18.5 3.89 62.24 320 4940 http://en.wikipedia.org/wiki/bleep_test Sports, exercise and health science teacher support material 16