I was eager to repeat the test after my marathon training to see how my fitness had evolved. Ideally, I would have done the test in early October towards the beginning of my taper. I was at the peak of my fitness then and would have had even stronger results than I had today. However, I decided to postpone it until after the marathon since I was experiencing discomfort in my hamstring/knee and didn't want to risk making it worse before my big race.
Today I had my reassessment and I am pleased (relieved?) to say that I have improved my fitness!
These are my updated heart rate zones. My "lay-person" interpretation of the changes in the higher zones is that as I've gotten more fit, I've become able to do more work at higher heart rates. The updated data suggests my maximum heart rate is 196. Maximum heart rate isn't a number you can "improve" with more fitness, you can just do more work at your maximum heart rate as your fitness improves. So back in June, I didn't even get all the way to my maximum heart rate during the test.
Here's some data that is easier to interpret. VO2 (volume of oxygen) max is the maximum amount of oxygen your body is capable of using at any given time. As fitness improves, you are able to use more oxygen and to work out longer and harder. My VO2 max has increased 2.5 percentage points, which is a nice improvement.
Again, here are some data that are pretty clear. In each zone, I've increased the number of calories I burn per minute. And I've taken advantage of that - I've lost 5 pounds since my previous assessment.
My speed has also increased for the upper zones. During the first assessment I maxed out at 5.9 miles per hour; this time I made it to 6.3 mph.
I think I look more fit now, too! The picture on the left is from the first assessment, and the picture on the right is from the second. Pretty cool, huh?