Lung capacity
When starting to exercise, such as going for a run, one feels short of breath. Not long into the run breathing becomes easy and the runner is comfortable once again. Does the lung capacity increase or are there other factors at play?

Set up a scientific investigation to answer the following questions.

1). Does Lung volume change with exercise?

2). Does resting lung volume differ with size or height of a person?

3) Does the air flow rate change with exercise.

Aim- To investigate how exercise changes the lung volume capacity and flow rate of air.

 

Apparatus

- A tape measure.
- Bathroom scales.
- 12 lung volume bags as shown on the right.
- 3 flow rate meters as shown on the right

Work in pairs

Method

Step 1 - Record your weight and height.

Step 2 -Take a deep breath and fill the lungs to capacity. Breath out the entire lung volume into the bag. Place the bag on a table and slowly squeeze the air to one end of the bag as shown on the right.

 

 

The end of the bag will start to lift off the table, your partner should be watching for this. At this point stop and take the reading of the volume of expired air. Click to see how.

Repeat this procedure 5 more times and average the results. Note each result should be very close, to within +/- 0.1 L.

Step 3 - Using the flow rate meter shown on the right, measure the flow rate of expired air.

Step 4 - This step involves the students running two kilometres in as close to 10 minutes as possible.

After completing the run measure the flow rate and volume of expired air as before.

Record the results on the board so that class results are visible to all students in a similar table as shown below.
Height
Weight
Lung capacity before exercise
Flow rate before exercise
Lung capacity After exercise
Flow rate before exercise
           
           
           
           
           
           
           
           
           
           
           
           
           
           
           
           
           
           
           
           
    Average= Average= Average= Average=

Construct a scatter graph of :
- Weight vs Flow rate
- Weight vs lung volume before exercise.
- Height vs Flow rate
- Height vs lung volume before exercise.

Are there any correlations between height and lung capacity?

Are there any correlations between weight and lung capacity?

Calculate the percentage change of both lung volume and flow rate after exercise.

Do your results suggest that exercise changes lung capacity or flow rate? If not, suggest what other factors might be responsible for making athletes more comfortable during a run after an initial period.

You may wish to use an external resource to draw a line of best fit of the data you have collected.