Heart Rate Investigation

[TNT]

I am currently doing an investigation on the effect of caffeine on the average heart rate of a boy after doing 10 minutes of exercise. Do you guys think it would work?

[Sandwich]

Well it'd be hard to say whether the increased heart rate would be to do with exercise or to do with the caffeine, so that would be problematic. It would make much more sense to do either caffeine or exercise. Just think of your variables and then whether you'd be able to control them all sufficiently to say your results reflected what you wanted to know.

[Charizard]

Theoretically it's fine. To devise a scientific experiment you need something you're changing, something you're measuring, and other factors that could affect the results must be kept the same. Here you'd be changing the amount of caffeine and measuring heart rate. Just make sure to keep the amount of and strenuousness of exercise constant.

It might be hard to do this experiment all in one session though, because doing previous amounts of exercise can change your heart rate later (warming up). You need to remember to wait until heart rate returns to resting rate before adding more caffeine and doing more exercise. Run it through with your science teacher; teachers usually have a generally good idea of what's appropriate and what isn't.

[Hedron123]

I totally agree with Sandwich, it is easier if you alter both variables separatedly and measure the effect of each. Be careful on how you are going to provide the candidates for the experiment with caffeine. I suggest you to use coffee because other forms of caffeine (a pill or an energy drink) might be considered as harmful for the body and sometimes this goes against the IB Code of Ethics. Once again, I recommend you to compare the increase in heart rate due to caffeine (you can provide the candidates with different doses) and due to exercise (maybe intermediate times of exercises i.e after 3 minutes, 4 minutes, 5 minutes, etc). You could then compare the trend followed by each to see which one increases the heart rate more, etc.

G'luck!

Regards.

[aya91]

Well one group in my class did their group 4 project about the effect of caffine on heart rate and blood pressure... And they did pretty well. They had to do the experiment on themselves though, because of the code of ethics mentioned above.