I have made these predictions because I believe that the supply of Oxygen to the muscles will decrease which will push the heart rate up. I also think that a lot of energy will be used up as the exercise takes place, thus resulting in a further increase. If the body is unable to continue aerobic respiration, anaerobic respiration will take place. This results in lactic acid (2C3H6O3) being formed. Finally, the CO2 levels would also rise which would also contribute to the heart rate rising.
Method
I will walk up and down stairs for 15 seconds at a time. I will then measure my pulse rate and my resps aswell. I will wait till my pulse rate retreats back to its resting level; this is to keep it a fair test. When it is back to normal I will add another 15 seconds each time onto the last time and measure my pulse n resps. After continuing this process till I have walked for 120 seconds, I will do the same experiment but instead of walking I will run instead. To make sure that this is a fair test I will walk up and down 15 steps, this is so that I walk the same amount of distance. I will also wait till my pulse goes back down to its resting level this enables us to record accurate results for measuring the effects of exercise on pulse rate.
Results
From these two graphs, we can see that exercise clearly does have an effect on pulse rate, as it has risen considerably compared to the resting pulse rate. When the amount of time was increased for the running, the pulse rates varied quite a lot. Pulse rate was definitely affected by the aerobic exercise, and did increase by a decent amount, and the pulse rate did not rise by a large amount when the amount of time was increased to 3 minutes, which is what I predicted. Our method for testing the prediction was suitable, and the experiment worked well and produced enough information in order for us to analyse.
Evaluation
Although I believe that my experiment produced fairly valid results, I am not sure that my experiment was particularly accurate. For instance, I cannot be sure that the running and walking was done at the same rate throughout the experiment. Also, I am not sure that the 15-second intervals were kept exactly to this timing.
If I were doing this experiment again I would have to look closely at the method of exercise I used. I think that exercising on a piece of equipment like a running machine would produce more accurate results because I would be able to guarantee that the exercise remained constant throughout this experiment.
Finally, an actual ‘pulse-meter’ might have helped the experiment to be more accurate. This is simply strapped round the chest of the exercise and it measures your current heart rate. I believe that this would produce a more accurate heart rate and destroyed any necessity to have the 30-second breaks during the exercise.