Homeostasis Lab: The Effects of Exercise on Homeostasis

 Adapted from Patti Carothers 08

A: Purpose

To discover the effect that various levels of exercise have on specific body parameters. 

B: Introduction

Exercise causes many homeostatic factors to kick in, in an effort to maintain internal homeostasis.  How exercise affects some of these homeostatic factors can be determined by measuring and observing the following five parameters:

-          change in skin color on arms and face

-          perspiration level

-          external body temperature

-          heart rate

-          breathing rate

In the following lab, two members of your group will exercise for 8 minutes by ___________________________ (pick an exercise that can be maintained for 8 minutes).  The parameters listed above will be recorded at rest, 2 min, 4 min, 6 min, 8 min, and 1 min after exercise has stopped.  The subject should stop at each interval just long enough for the needed measurements to be taken, after which exercise should immediately resume. 

C: Hypothesis:  Predict the changes that will occur in the five observed body parameters listed above in part B. Be sure to address each one of the five.

 

 

 

D: Procedure: Split your lab group into two subgroups so you can average the results.  Subjects in each subgroup must do the same exercise.

1.  Each group should obtain: a thermometer and have a cell phone to use for a stop watch.

2.  Record the resting observations and values of your subject for each of the 5 parameters.

  1. Qualitative observation:  Record normal skin color of hands and face (i.e. pale, pink, red, etc.)
  2. Qualitative observation:  Record normal perspiration level by placing one 1x1 inch piece of tissue onto the forehead and observing the amount of moisture on the paper (i.e. none, mild, medium, high, etc.) 
  3. Record external body temperature by placing the thermometer under the subjects arm pit for one minute (note: measurements should be taken directly from the skin).  Clean the thermometer with alcohol and a tissue before taking measurement.
  4. Determine the breathing rate by counting the number of breaths taken in 30 seconds and multiply by 2 to give a one minute value.
  5. Determine the heart rate by taking the radial pulse for 30 seconds and multiply by 2 to give a one minute value.

3.  Have your subject begin to do the chosen exercise without stopping.  Please note your subject should be sure to exercise at a level they can maintain for the entire 8 minutes and keep at that pace.

4.  Take your subject's parameter readings using the same techniques described above at the 2, 4, 6, and 8 minute intervals. Take the measurements quickly within 30 seconds so that the level of exercise intensity is not drastically affected by this brief period of "rest".  Be sure to take final readings 1 minute after your subject has stopped exercising and is recovering.

5.  Record all of your parameter readings in the table below.

6.  Share data among the lab table's subgroups. 

7.  Return all of the lab materials to the supply table.

E: Observations 

 Subject #____

 Body Color (example: no change, pink, red, pale)

Perspiration Level

(example: no change, slightly wet brow,/facial areas, moderately wet brow/facial areas, very wet brow/facial areas)

Body Temp (Celsius)

Conversion from Fahrenheit to Celsius:

  • Begin by subtracting 32 from the Fahrenheit number.
  • Divide the answer by 9.
  • Then multiply that answer by 5.

Online conversion calculator:  http://www.worldwidemetric.com/Measurements.html 

Heart Rate (beats/min)

Breathing Rate

*Count the number of breaths by the rise and fall of the chest as one breath

REST/ BASE LINE 

 

 

 

 

 

 AFTER 2 min of exercise

 

 

 

 

 

 AFTER 4 min of exercise 

 

 

 

 

 

 AFTER 6 min of exercise 

 

 

 

 

 

 AFTER 8 min of exercise 

 

 

 

 

 

 1 min after exercise HAS STOPPED 

 

 

 

 

 

F: Graph Analysis

Plot the lab table's AVERAGE measured data  (body temperature, heart rate, breathing rate ) on one graph.  You should plot one graph using 3 different colors: for body temperature use RED, heart rate use BLUE and breathing rate use GREEN.  CREATE A LEGEND, TITLE, AND MARK THE UNIT OF MEASUREMENT FOR THE GRAPH.

 

G: Post Lab Questions

1.  Does the data support or refute your hypothesis (prediction)?  Explain.

 

2.  How is does this lab demonstrate homeostasis?

 

 

 

3.  If the experiment were to be repeated, what are two ways it be improved?