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This lesson plan is deliberately spelled out in a great deal of detail, because it is intended to support massage teachers at all levels of experience. You may find it provides more detail than you need at your particular level of experience, but that's ok--take what you like, and don't worry about the rest.

If you find it was missing some details that you needed, please click here to explain how this lesson could be modified to provide the information you need.

Table of contents

 

• Purposes of this exercise
• Measures of success
• Necessary equipment provided by the teacher or by the school
• Timing the exercise
• A. Getting started
• C. Analyzing the data

Purposes of this exercise

• To reinforce the students' theoretical knowledge of blood pressure by grounding it in an application of massage;
• To stimulate the students' sense of fun and discovery at seeing theoretical learning come to life under their hands;
• To develop the students's sense of critical thinking as they analyze the meaning of the results they see.

Synopsis of this exercise

1. The teacher (you) provides a short training to the students in how to measure blood pressure.
2. The students test the research question "Does massage lower blood pressure?" by performing massage on each other, and by measuring the blood pressure of the student on the table or chair before and after the massage.
3. The students graph their results to see whether blood pressure is actually lower after the massage than it was before it.
4. The students discuss what kinds of experimental error or other confounding factors could have influenced their results.

Steps 2 and 3 of the exercise

 

Video demonstration of this exercise available here.

Measures of success

1. The student is able to explain what blood pressure, systolic blood pressure, anddiastolic blood pressure are.
2. The student is able to explain how blood pressure cycles between systolic anddiastolic pressures.
3. The student is able to name the range at which blood pressure is considerednormal.
4. The student is able to name the range at which blood pressure is consideredborderline.
5. The student is able to name the range at which blood pressure is considered high.
6. The student is able to define hypertension.
7. The student is able to explain the effects of high blood pressure on the body, and why it is desirable to lower high blood pressure.
8. The student is able to define orthostatic hypotension.
9. The student demonstrates precautions to protect the client from the effects oforthostatic hypotension after a massage.
10. The student can explain the difference between a false positive error and a false negative error.
11. The student can describe at least one potential source of error in how this exercise was carried out.

Answers and theory behind these measures in the Teacher's Guide.

Preparation for the exercise

Necessary equipment provided by the teacher or by the school

• Blood pressure monitor

  If you choose this option, you should expect to pay at least $100 (at the time of this writing) to buy a good-quality stethoscope new, but it should last through multiple classes over the years.

   

  • If you know how to measure blood pressure with a manual (inflatable-cuff) sphygmomanometer and a stethoscope, it can be fun to give the students the experience of doing it "old-school", but in that case, you should invest in a dual-headset teaching stethoscope (sample picture here) so that you can also hear what the student is hearing, and coach them on the blood pressure sounds. Otherwise, the task of learning how to hear the sounds (not within the scope of MT anyway) is likely to be frustrating enough, and to use up enough time, to take a good deal of the fun out of the exercise.
  • Investing in a digital monitor is simpler, and can get to the task of actually measuring blood pressure faster. The trade-off for the ease of use is that they tend to be more inaccurate than the sphygmomanometer + stethoscope method. Choose a model whose cuff goes over the upper arm, rather than the wrist or the finger, as the upper arm measurement is more accurate. At the time of this writing, you should expect to pay about $75-$100 for a good-quality digital monitor that will last through several classes. Googling on digital blood pressure monitor reviews can provide information that will be useful in making your choice of make and model.

     

  • Whichever method you choose, you and the students should be aware that an average blood pressure cuff will be more accurate for taking blood pressure measurements on people who are of average size. Readings taken on people who are very large or very small may be inaccurate, unless you have an appropriately-sized cuff for them.
• Massage table or chair for each team/group of students
• Whiteboard and colored markers: any changes in blood pressure will be easier to see if you can assign a different color of marker to represent each "client" in the data graphed on the whiteboard

Necessary knowledge the teacher (T) and the students (S) should possess

• T, S: Circulatory and blood pressure: Foundational Concepts
• T, S: How to perform a 15-minute slow-stroke back massage
• T, S: How to draw a line graph
• T: Measurement and experimental error: Foundational Concepts

Timing the exercise

For every "client" who receives a massage and gets his/her blood pressure measured, you should permit about 30 minutes from start to finish. The massage itself will take 15 minutes, and before the massage begins, there is a certain amount of preparation, including taking the first blood-pressure reading. Then, after the massage, a second reading is taken, and the results are graphed on the whiteboard. By the time this all takes place, 30 minutes is a reasonable estimate. Let's call this sequence of events for an individual client a trial. Steps 2 and 3 in the figure in the Synopsis above make up one trial.

How many trials you will want to do in this exercise is a judgment call, and you know your class, so you will have the best sense of how long you should spend on this exercise. From experience, I would recommend spending a maximum of about an hour (2 trials' length) on the massage and blood-pressure measurements--much more than that, and attention spans and enjoyment tend to start diminishing.

Even that length of time can provide an opportunity for everyone to administer a massage and receive a massage in turn, if the class is small enough, by dividing the class up into teams of 2 people. Then, after the first trial, they switch, and the one who received the massage the first time performs it in the second trial.

For multiple teams, the availability of the blood-pressure monitor can become a bottleneck if everyone needs it at exactly the same time. You can avoid this problem by staggering the start times for each team, as in Figure 1.

Notice that Team A finishes first, and that Teams A, B, and C are all finished while Team D is continuing to massage and measure blood pressure. Having the teams compare their results can be a fun way to use that extra time. Just make sure they don't talk so loudly they interfere with Team D's finishing their work, as the accuracy of the results depend on the "client" remaining as still and quiet as possible.

If you have more than four teams, and only one blood-pressure monitor, then this extra time at the end for the teams that have finished will start to become excessive at some point. If they are going to run a second trial, they may still have to wait before they can begin it for the blood-pressure monitor to become available.

If the students are standing around being bored, or if they get distracted from the lesson and start acting as if they are on break, then the learning opportunity is starting to get lost. To cut down on the risk of this much dead time, four teams is probably a good maximum number of teams to perform this exercise with, although your class may be able to handle more or less. You'll make that judgment call based on how you expect your class to balance between the activity and the down time between trials.

Part of the fun of this exercise is having everyone have the chance to both give and receive a massage, but if you have a really large class, then sticking strictly to that idea may lead to too many teams and too much down time while students are waiting for the monitor. In that case, you will have to form teams where not everyone has the opportunity to give or to receive a massage. Assigning roles to the members of the team who are not giving or receiving the massage (time-keeping, writing down the readings, making silent obervations about the massage and writing those observations down for the discussion afterward, and so forth), it will cut down on the risk of having students standing around with nothing to do.

To prepare for carrying out the exercise in your class:

1. Get an appropriate blood pressure monitor, and make sure you know both how to use it, and how to teach someone else to use it.
2. Decide how many teams and how many trials are the best balance for your class.
3. Decide how you are going to assign members of your class to teams.
4. Prepare any handouts, presentations, or other class materials you want to use.
5. Use the Measures of Success to determine what questions you will ask the students, and what skills you will watch for them to perform, in order to evaluate how well they understand the material.
6. Make sure that you know how to draw two line graphs, one with time as the x-axis and systolic blood pressure as the y-axis, and the other with time as the x-axis, and diastolic blood pressure as the y-axis.
7. Make sure that the students know how to draw line graphs; if they need instructions, refer them here.

Carrying out the exercise

A. Getting started

When the class meets for the exercise:

1. Review the material on blood pressure that the students are expected to know.
2. Remind the students about orthostatic hypotension, and how they should help the clients to get up slowly after the massage, and not have the clients stand up if they feel any dizziness.
3. Explain what the students are going to do in this exercise and why they are doing it.
4. Show the students how to measure blood pressure with the blood pressure monitor.
5. Divide the class up into teams, and have each team decide who is going to be the first "client".

B. Massage and measuring blood pressure

Give each team their instructions, make sure that each team has some way of keeping time, and begin the first trial:

1. The person who is administering the massage (or another team member) asks the client to get into position to receive a back massage on the massage table or chair.
2. One of the team members reminds the client not to move or talk until after the entire trial is finished, since that can affect blood pressure readings.
3. When the client is in position to receive the massage, put the blood-pressure monitor on the client, and take the before-massage blood-pressure measurement.
4. Write down the reading on a piece of paper to be transferred to the whiteboard later.
5. Remove the blood-pressure monitor, and begin the massage. Either the person giving the massage or another member of the team should watch the time closely to make sure the massage lasts exactly 15 minutes.
6. When the massage ends, remind the client not to move or talk.
7. Measure the client's blood pressure once again, and write down the readings.
8. Taking appropriate precautions against orthostatic hypotension, have the client get up from the massage table or chair.
9. Repeat steps 1 through 8 for as many trials as you have decided your class will hold.

When all the trials are finished, the students will analyze and discuss their results. This will help them to determine whether there was any change in anyone's blood pressure after they received a massage.

C. Analyzing the data

Ask one student to draw a line graph to receive all the systolic readings, and another student to draw a line graph to receive all the diastolic readings. The charts should have two lines marked on the x-axis, indicating the before-massage measurement and the after-massage measurement. The y-axis should be marked off in units of 10 from 0 to 200. Before any measurements are entered, the graphs should look like this:

Ask each team to graph their results on the whiteboard. All of the systolic results should go on the first graph, and all of the diastolic results should go on the second graph. If two or more teams need the same number, have them plot it so that all colors at that number are visible.

The changes can be most easily seen if each client's results are graphed in a unique color. For example, let's say that Team A conducted 2 trials, and their data looks like this: Client 1 blood pressure 132/74 before massage, 126/68 after massage, and Client 2 blood pressure 118/86 before massage and 104/82 after massage.

 

The first thing to do to make this easier to graph is to draw two tables. Table 1 will be the data for Graph 1 (Systolic blood pressure), and Table 2 will be the data for Graph 2 (Diastolic blood pressure).

 

 

 

Then the students plot the data from the tables into the correct line graph (red for Client 1 here, and green for Client 2). The data will probably show a fall in blood pressure from the before-massage reading to the after-massage reading. If it does not, tell the students that that is nothing to worry about, and that you will all discuss it in the analysis part of the exercise.

 

When all of the data are plotted, and the lines on the graph can be compared with each other, it's ready for the class to discuss the meaning of their results.

Ask the class what trends they see in their results on the graph.

• Does blood pressure tend to go down after massage? How can they tell?
• Do all the clients show about the same amount of change, or are some lines much steeper than others?
• Did anyone actually show a rise or stay the same?
• What else do they see looking at the graph? Are there any noticeable patterns (trends) in the data? If so, what do the students think those mean?
• Did they see anyone with high or low blood pressure on the graph? How should they handle suspected high blood pressure in a client in an ethical way, given that we do not diagnose?

For the purposes of this exercise, we'll concentrate on qualitative (descriptive) discussion of what experimental errors may be in our method, rather than quantitative. Since the samples from classes are usually quite small, we won't get into the mathematics of calculating power and statistical significance. We can just agree that the results from this exercise are from such a small sample size, and that we have not taken sufficient precautions against experimental error, that we cannot generalize from them.

There are a few very important sources of experimental error that the students should come away from this exercise knowing about. Try to have the students think about these possibilities, and come up with them by themselves, rather than teaching them, if that's at all possible. They may be able to come up with others as well, and discussion of these possibilities should be encouraged.

In examining our results for error, we are trying to avoid 2 different, but related, traps. We don't want to see an effect when there isn't really any, and we don't want to miss an effect that is really there.

Lack of controls: One of the most important sources of error in the way we conducted this experiment is that there is no control we are testing against. So we cannot rule out the possibility that we are giving massage the credit for a change that would have happened anyway. Remember that activity and speaking can raise blood pressure, and we had the client lie still and silent for the entire trial. So it may be that the act of lying still is what lowered the blood pressure, rather than the massage. Or, for that matter, it may have just been due to chance that the blood pressure went down in that window of time. Without a control, we cannot tell the difference. That means that we run the risk of a false positive here--attributing blood-pressure lowering effects to massage, when it was really due to having the client lie still.

Lack of blinding: Another very important source of error is that everyone in the room knew what was going on. In a real study, we would have separated the ones who performed the treatments from the ones who analyzed the data, and we would have given the clients the fullest disclosure for informed consent that we could have done without compromising the results that we get from those clients. In other words, the MTs and the clients would have been blinded, in order to avoid bias in the measurements.

Bias is very different from cheating; we are not saying at all that the teams falsified their results. But there is a natural human tendency to want things to work out right, so knowing the purpose of the study, the teams may have interpreted any judgment calls that may have arisen in a way that would be favorable to supporting the hypothesis that massage lowers blood pressure. For example, let's say you chose to do this old-school, with the manual inflatable cuff and the stethoscope. There is often some ambiguity in this method--"is that really a blood-pressure sound I am hearing or not?". If you know what results you are hoping to get, you may be inclined to resolve ambiguities that arise such as this in a way that is favorable to the results you want to get--without even realizing it.

Observer-expectancy effects: Another possibility is the Hawthorne effect (where the very act of studying a behavior improves the study subject's performance), the observer-expectancy effect (where the study subject responds to the investigator, rather than to the treatment), and other ways in which the clients can improve in response to the study situation or investigator, rather than to the intervention being studied. The fact that the clients knew what was going on, rather than being blinded, raises the very real possibility of false positives.

Measurement error due to unfamiliarity with equipment: Yet another potential source of error is the students' unfamiliarity with the equipment used to measure blood pressure. It could have been used inconsistently from one measurement to another, changing those measurements slightly and creating either false positives or false negatives, depending on those changes.

Environmental factors: There may have been noise, distractions, or other factors in the environment that detracted from the client's ability to relax while receiving the massage. In that case, you may see false negatives--it looked like massage didn't lower blood pressure, when in reality, the client never got the opportunity to get the benefits of massage.

While we are not going to explicitly calculate power for this study, the fact that it is such a small sample of clients means that it is very likely to miss an effect that is there (false negative).

The more you can get the students to come up with these and other factors, rather than being told about them, the more fun and lively the discussion is likely to be. Make sure that the students come away from this knowing that:

• If their results show that massage lowered blood pressure in their "studies", that is consistent with what much of the literature on the subject claims;
• If their results do not show those trends, they haven't "disproved" any benefits of massage, nor have they necessarily made mistakes--it's all part of a much larger picture that has to all be taken together in order to get any meaningful knowledge from it;
• while the way this study was conducted did not take care of all the potentialmethodological errors that could have arisen, it is a glimpse into the world of research into massage, and these methods can be refined into observing and writing up case reports.

Good luck, and I hope you and the students have fun with this exercise!