I had a really beautiful ride on my bike this evening. I chose to explore another new area and as you can see from the photo, I discovered yet another really cool looking barn.
My ride was 90 minutes long and was supposed to be an easy, Zone 1 / Zone 2 ride. It turned out to be much more interesting than that.
As I got to the new area of my ride, I was hoping for some nice flat roads through farmland, with great views that I could enjoy. What I found however, was a road through woodland, that was like a roller coaster and a steep roller coaster at that. I found myself going up short steep inlines with gradients over 10% and then, immediately descending down equally steep inclines. Throughout the ride, I was constantly climbing or descending, although the hills became less steep later on.
These ‘hill repeats’ meant that I was not able to stay in my target power zones of zone 1 or 2. I found myself hitting at least zone 4 going up the hills and basically coasting down them. In other words, my power output throughout the ride was highly variable.
There is a way of measuring the variability of your power output on a ride. It is called the Variability Index or VI. It is calculated by dividing your ride’s Normalized Power by its Average Power. I high VI number (something over 1.2), means that you put in a good number of high power surges during your ride. These high power surges are very demanding on your body and sap energy.
For triathlon racing, VI is actually quite a good number to pay attention to. You want to keep your VI on the bike, as close to 1.0 as possible. By doing this you are not “wasting” energy on surges, and you can “keep” that energy for the run.
My ride tonight would not have been good for a triathlon race. My VI this evening was 1.29. That is one of the highest numbers that I can recall seeing for one of my rides. The good news is that the route I chose tonight, would not likely be chosen for a triathlon race.
Even with all the hills, it was a great route. I had fun doing it and am planning to do part of it again on my long ride this weekend.
