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NIDA

Is Posture Really Important?

Revised June 2012

Background

By: Ethan Evans, Austin Watters, Connor Hanson, and Adib Babaei | Coppell High School, Coppell | Grade Level: Elementary School | June 6 2012

Posture can have a big impact on you. Good posture helps you to breath, prevents your back from hurting, makes you taller, and supports a strong body. Many people slouch or lean forward rather than standing up straight. But what happens when you have bad posture? This experiment will demonstrate what can happen when you don’t stand up straight.

Figure 1. Examples of bad and good postures.

Illustration showing good and bad posture poses

Objective

This experiment will show what happens when a wooden ruler and a flimsy ruler are exposed to weight. It simulates what happens to a person with good posture vs. bad posture. 

Hypothesis

The sturdy ruler (perfect posture) will be stronger and will not bend when weight is placed on it. The flimsy ruler (poor posture) will bend when weight is placed on it.

Duration

Total actual in-class time: 40 minutes
Set-up time: 5 minutes
Experiment’s run time: 30 minutes
Take-down time: 5 minutes

Materials

  • 1 wooden ruler (good posture)
  • 1 flexible/flimsy ruler (bad posture)
  • 2 support blocks for the rulers
  • 1 weight (preferably about 100 grams)

Safety Considerations

This experiment is not considered hazardous.

Procedure

  1. Place supporting blocks 6 inches away from each other.
  2. Place the wooden ruler across the 2 supporting blocks.
  3. Note whether the wooden ruler bends without any weight on it.
  4. Place the 100-gram weight on the wooden ruler.
  5. Examine what happens to the ruler.
  6. Remove the weight.
  7. Do not change the distance between the supporting blocks.
  8. Place the flexible ruler across the two supporting blocks.
  9. Note whether the flexible ruler bends without any weight on it.
  10. Place the 100-gram weight on the flexible ruler.
  11. Examine what happens to the ruler.

Data Analysis

  1. What happened to the wooden ruler when it did not have the weight placed on it?
  2. Did placing the weight on it cause any changes?
  3. What happened to the flexible ruler when it did not have the weight placed on it?
  4. Did placing the weight on it cause any changes?
  5. What does this tell you about posture?
  6. Why did you look at the rulers before placing the weights on them?
  7. Why is it important to use the same weight on both rulers?

Conclusion

The wooden ruler does not bend when weight is placed on it, whereas the flexible ruler does. This is similar to good posture vs. bad posture. Looking at the rulers before weights were placed on them allows you to know what “normal” (the control) is in an experiment. Once you know what “normal” is, you can conduct the experiment and compare the results with the “normal.”

Relevance to the NIH Mission

Students will have the opportunity to conduct an experiment, including controls. This will introduce them to the concept of an experiment and why a control is necessary.

This page was last updated June 2012