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Heart Rate Experiment

The purpose of this activity is to learn more about your heart and fitness. Like any muscle, your heart benefits from proper exercise. But how can you give it the best workout possible? And how much control do you have over your heart rate? We’ll begin by experimenting on how different conditions affect your heart rate.

What are the effects of ______on my heart rate?

In the procedure, youcan perform various activities that you think will vary your heart rate. These tasks are your independent (manipulated) variables, and they can include things like:

  • Various forms of exercise (running, walking, jumping, etc.)
  • Various forms of relaxation (lying flat, sitting, meditating, etc.)
  • Various forms of altered breathing (holding breath, slow-breathing, fast-breathing, etc.)
  • Various forms of other stimulation (temperature, different levels of light/darkness, listening to loud music on an iPod, stress, anxiety, fear, etc.)

The dependent (responding) variable will be your heart rate, and youcan measure that by taking your pulse for fifteen seconds immediately after each activity and then multiplying by four.

Here are several things to consider:

  1. Design an experiment that you can probably complete in a fifty-minute class period.
  2. After each activity you undertake, allow your heart rate to return to normal before proceeding further.
  3. Include some activities that are certain to raise your heart rate to a high level, but don’t do anything more demanding than running for a few minutes. Everything should be SAFE. No one should pass out or even come close.
  4. You need to provide any special materials you will need.
  5. You can vary this experiment to suit your personal interests.

Keep in the back of your mind thisconclusion question:

“Why does my heart rate respond the way it does in each of the situations I examined?” Set up your experiment so you will be able to answer that question and will see some interesting differences in your heart rate.

As we work in class, we’ll also consider these important questions about heart rate:

  • Why exactly do physical conditions affect your heart rate?
  • Why exactly do emotional conditions affect your heart rate?
  • Why does your resting heart rate matter, and what does it tell you?
  • What’s the “target heart rate” you should aim for during exercise?

Heart Rate Experiment (draft)

Purpose:

Hypothesis:

Activity / Predicted Heart Rate in beats per minute (bpm) / Why?

Procedure:

Results:(you can use this space to record your results)

Activity / Actual Heart Rate in beats per minute (bpm) / Notes

Writing a strong conclusion:

  1. EXPLAINING: For each of the activities you undertook, provide a one or two sentence answer to this question: “Why did my heart rate respond the way it did in each of the situations I examined?”
  2. Physical activities: For example, if your heart rate went up after running, you can explain that since your energy output was higher, your muscles needed more fuel (oxygen and glucose) and so your heart responded to that need by pumping blood more vigorously to those muscles. (And by the way, how do your lungs respond in that situation? And although you don’t notice, how do you think your liver responds in that situation as well?)
  3. Emotional activities: If you placed yourself in a stressful/anxious/fearful situation, or if you placed yourself in a relaxed situation, those emotional conditions can trigger strong heart rate changes as well. Look at the series of videos linked to the Heart, Blood and Cardiovascular System page of the course website below the heading “Heart Rate Experiment”. These videos will teach you more about the “fight or flight” response and the “relaxation” response. Use your conclusion to show that you understand how emotions can play a part in your changing heart rate.
  1. EXPANDING: The point of doing vigorous exercise is, among other things, to strengthen your heart so that it’s in great shape. Exercise physiologists have determined a target heart rate that should be your goal while exercising. Exercising at your target heart rate at least three times a week for thirty minutes strengthens your heart and is a great prescription for heart health. To determine your target heart rate:
  2. Start with the number 220.
  3. Subtract your age.
  4. Now calculate 50% of that number and 75% of that number.
  5. Your target heart rate is the range between those two numbers.

If you exercise at a heart rate below your t.h.r., there’s nothing wrong with that, but you’re not getting the best workout possible. If you exercise at a heart rate above your t.h.r, there’s nothing wrong with that either, but chances are you’ll get tired very quickly and stop the exercise, thus not gaining the positive effects of a good thirty minute workout.So what is your target heart rate and what are some activities that you can do for thirty minutes at your target heart rate?

  1. CONNECTING: Lance Armstrong (despite everything) and Michael Phelps are two of the world’s greatest endurance athletes. They have spent thousands of hours exercising at their target heart rates. Armstrong and Phelps are reported to have had resting heart rates in the 30’s or 40’s while at the height of their careers. Why were their resting heart rates so low? If you start or continue a strong exercise program from now until you are, say, 40, what will happen to your resting heart rate? Why does that happen and why is that a good thing?