How does exercise affect pulse rate?

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How does exercise affect pulse rate?

Planning:

I am doing an investigation to find out how exercising affects peoples pulse rate. Your pulse is the rate at which blood is pumped around the body by the heart. We measure this in bpm (beats per minute) because this is the most practical way to measure it. The variables that can have an effect are how long a person exercises for, whether the exercise is high or low impact and how fit the person is. The input variable is how much/little the person exercises and the output variable is the persons pulse rate.

I am going to investigate if exercising for different periods of time affects somebody's pulse rate. I will do this with a group of five people (including me), each person will exercise for periods of 2, 4, 6, 8 and 10 minutes. We chose these times because we felt that exercising over a 10 minute period will show more changes in pulse rate, exercising for less than 10 minutes may not produce as good results as your pulse rate may not vary as much. People may not be able to exercise constantly for more than