How to Measure Vital Capacity Using a Balloon

In this video, I show how you can calculate your vital capacity (the maximum air you can breathe in one breath).

First you would measure your "expected" vital capacity for your height and weight using a couple formulas.

Then you would measure your "actual" vital capacity by breathing into a balloon and measuring the balloon's diameter.

Lastly, you would measure how well you meet your Expected Vital Capacity by calculating the percentage. Over 80% is considered normal.

I use this lab when teaching the Scientific Method to my students. I have them test whether or not athletes will have a higher vital capacity compared to non-athletes, and then we graph our results on a bar chart.

Surprisingly, many of my students were between the 60 - 80% range which is not considered normal; this could mean they weren't doing the calculations right or perhaps because they need to exercise more. :) Even one of the football player's vital capacity was in the high 60's.

I did find that the students who were at 100% vital capacity ran on a regular basis.

I run 2 miles a day and my vital capacity was normal (83%).


Sources:
sciencebuddies.org/science-fair-projects/projec…
en.wikipedia.org/wiki/Lung_volumes
medical-dictionary.thefreedictionary.com/vital+…