Notes
Wow, here it is happening again, where once the weather cools down I have to run a kind of fast to keep the heart rate up in the working zone. Part of me wants to call this a lower aerobic run because even though I felt like I was working the pace and my body quite hard, I really only touched on true upper aerobic heart rates.
I feel like I need to do this kind of run to get to a higher level of speed endurance, but the concern is the toll it can take on my legs. I think I have to keep to slower, longer runs two to three days a week while programming in one to two of these.