Today I set out to do some interval training. Normally, for me that means doing 3 or 4 mile splits on the treadmill at about a 5:40 pace, with 3 or 4 minutes walking in between. One of the things I’ve come to realize about my interval routine is that mile splits are probably too far of a distance to be training at the lactate threshold. According to Wikipedia, “muscles trained under anaerobic conditions (ie, lactate threshold) develop differently, leading to greater performance in short duration, high intensity activities, which last up to about 2 minutes.” So from now on, I think I’m going to switch over to half mile splits, which are closer to the 2 minute mark, in order to more properly train my anaerobic system.

But back to today, where I ran my first mile in about 5:40. It felt good, steady breathing and no muscle soreness. Except I had a nagging popping sensation on the back side of my right knee. I knew better than to keep pushing it, lest I wind up with a new injury to gripe about. So I switched over to some hill training, at a slightly slower pace. In his book The Daniels Formula, Jack outlines a chart that demonstrates the impact of hills on a speed workout. Basically, as you raise the incline on a treadmill, the pace equivalent that you are running at gets progressively faster, compared to what it would be on a flat surface. Here’s the chart…