‘A major research programme carried out in the United States in the 1990s concluded that people who take regular aerobic exercise acquire some protection against coronary heart disease, high blood pressure, diabetes mellitus, osteoporosis (fragile bones), bowel cancer, and depression. There is also evidence that low levels of activity are associated with markedly increased death rates from a range of diseases. Increased activity, even in middle age, reduces that risk further.’
That source was taken from Microsoft Encarta, this evidence shows that even if the exercise increases the heart rate for a short moment in the long term it will help the heart and blood pressure.
I also know from my own experience that when exercising your breathing rate increases, this also means your respiration increases. This helps the body get a lot more energy from the oxygen taken in it also helps fuel the glucose with in the body. I also feel this helps prove my hypothesis if the body needs more energy around the body when exercising then the pulse rate has top increase to supply this new need for energy. When my candidates do the exercise they’ll be using aerobic respiration due the length of the exercise. Aerobic respiration is when the body releases a lot of energy in taking oxygen, this produces carbon dioxide as well as energy.
‘The rate of the pulse varies from 150 beats per minute in the embryo to about 60 in the aged.’
From this source again taken form Encarta, it shows me that people all have different pulse rates. When I take the pulse rates I shall not just look at their pulse rates compared to each other but I’ll compare their pulse rate difference from the relaxed rate to the pulse rate after exercise.
Obtaining Evidence
Equipment needed: ▪ 4 cones
▪ Long distance measuring wheel
▪ Stop watch
6 candidates: OWEN WILLIAMS, male aged 15
KATY GAMBLE, female aged 15
SCOTT BRISTOW, male aged 14
LILY GILES, female aged 15
ANDREW BROWN, male aged 15
SHARON BOUGH, female aged 14
- I weighed each candidate to find their mass, in kilograms.
- Each candidate then relaxed for 10 minutes to resume their normal pulse rate. I took the candidates pulse rate to make sure it was a fair test.
- I measured out an accurate 20m track for the candidates to run and walk up and down; I showed the distance using cones. The track was also only 1m weighed to make sure the candidates stayed in a straight line not having to travel further than any other of the candidates.
- I then got each candidate in turn to walk 200m (10 times along the track) I watched at one end while someone else watched the other making sure the candidate touched the end of the track;
- I timed each candidate seeing how long it took them to walk this length in seconds.
- Directly after this exercise I measured their pulse to calculate the difference from their normal rate. I wrote down my recording and carried on with the experiment.
- Each candidate then with out more than 1 minutes rest ran 200m (10 times along the track)
- I timed each candidate seeing how long it took them to run this length in seconds.
- I then directly after this exercise measured their pulse to see if this exercise had changed their pulse even more.
To make sure the experiment was fair; I made the candidates have to touch the line with one foot then turn and work again up the 20m strip. Each candidate had to walk in a straight line so each candidate would walk the same distance. If I was able to use a longer and safer strip of surface I would have but this was the longest and safest area I could use to make the experiment fair.#
To find the pulse rate I held each candidates wrist, I counted each beat for 15seconds, I then times that number of beats by 4 to get the total number of beats per minute.
I recorded my results for each person on a chart I later put the results into bar graphs this made analysing the results much easier I also introduced a line of best fit for each graph.
Analysing Evidence and Drawing Conclusion
The evidence gained from the experiment shows a lot, for one it shows that my hypothesis is correct but it also shows other evidence that supports other hypothesis. One of the main patterns I have noticed from the experiment is that the more time taken to do an exercise the lower the rate increases. So if some one runs 200m in 56 seconds their pulse rate will have increased much more than someone who ran 200m in 134 seconds.
Information gained from results:
- Weight does not always affect relaxed pulse rate or the pulse rate difference from exercise.
- The more exercise done the higher the pulse rate difference.
- The less time taken to do an exercise compared to someone taking more time is that the heart rate of someone doing in less time is much higher.
- Running increases the heart rate more than walking.
From the experiment I also noticed that the average increase for someone from relaxed pulse to a walking pulse rate is 10 beats per minute. The average increase for someone from relaxed pulse to a running pulse rate is 25 beats per minute. But each increase really depends on how fast the person is running.
The evidence also proves my research correct, that the more energy needed mean higher the pulse rate due to the increasing need for energy which is produced from the oxygen taken in from breathing and the only was to get this energy around the body is the blood system so the pulse increases so more energy can be pumped to the body. This means that the candidates aerobic respiration increases producing more energy carbon dioxide
Aerobic respiration:-
C12H12O6+6O2 6CH3CHOHCO2H + ENERGY
GLUCOSE + OXYGEN CARBON DIOXIDE+WATER+ENERGY
Evaluating Evidence
From this experiment we can see that the procedure used could have been more technical increase reliability of the results. Human error could’ve been avoided using a pulse reading machine instead of myself taking the readings.
I feel the area the experiment was taken place on , needed to be just one straight length instead of candidates having to turn this uses up energy not needed and some candidates could’ve have travelled further. I also feel I needed more time to make the experiment a fair test. The candidates needed longer to rest and to make the results reliable the candidates should’ve all ran and walked at the same time giving no unfair advantage as some candidates obviously had longer to rest.
Some results seemed unreliable the main result I felt least reliable was Katy’s her pulse rate from when she was relaxed to after she had walked 200m had not changed I think from my research and past comments this could’ve been avoided using a pulse reading machine. I also think I needed to repeat this procedure to get an average and widened result that would’ve have been more accurate. The procedure was suitable for my hypothesis but any more technical hypothesis would have needed a different strategy.
Evidence was not always reliable but gave an almost regular pattern. In further experiments I shall use more reliable sources for results such as the pulse reading machine. To add to the results we could do different exercises to get a wider idea of what exercises change the results more. The experiment could also be added to by getting a wider range of candidates more of an age range and more people to give a more reliable final result.
