So how does one measure their VO2 Max level? Well, it has to be done scientifically, using measuring equipment while one works out on a treadmill, but it can be approximated with something called a Rockport Mile Test. Essentially, you walk a mile, with no running, as fast as you safely can (please note, if you are not used to working out, it could be dangerous to do this, so consult a doctor) and then take your pulse immediately upon finishing the walk. Ideally, the mile should be as level as possible. Then you plug the results, along with your age, weight, and sex into the web site above, and it will calculate your VO2 Max.
In my neighborhood, I have a measured mile that I am confident is within feet of a true mile, as I measured it with a GPS - actually, 0.5 miles each way. And while it is not perfectly level, neither is it excessively steep. So tonight, I decided to take the test. I felt like I would get a cardiovascular fitness rating of "good," and I was right. My walking mile time was 13 minutes and 25 seconds. My pulse rate immediately upon finishing was about 144 beats a minute, more than double my resting pulse of 60-64. Plugged into the formula, my estimated VO2 Max value was 34.95, which is on the high side of "Good" for males my age.
This is interesting stuff, and I plan on exploring this a bit more in weeks to come as I try to gauge my level of fitness. I think I might research ways of improving our cardiovascular fitness, try some of those, and see if my Rockport Mile results go up over time - or down. I imagine there is some variabilty about the exact time to walk a mile. Or maybe this weekend, I will go to a track and do four laps and see if there is any difference, a track being perfectly level.
If you go to that website, you will see that your age affects interpreting the results. For example, my estimated VO2 Max value of 34.95 is considered a good fitness level for my age. But for males 10 or 15 years younger than I am, it would only be considered "Average." And for men 35 years younger, it would be "Poor."