In the past, I would never have been "okay" with a 9 mile run that took this long. I've owned a heart rate monitor for a few years and occasionally I've used one to get some feedback on my running or cycling, but I haven't really used it purposefully. A while back, I stumbled across a reference to the Maffetone method and the benefits of training just below the aerobic threshold for extended periods of time. With a long winter ahead, it seemed like a good time to give it a shot.
Dr. Phil Maffetone developed a method for calculating the aerobic threshold. This threshold is important because it is the dividing line for your body between converting fat for energy versus utilizing glycogen and blood glucose (which occurs at the anaerobic level). The best way that I've heard it described was in an article by Mark Cucuzzella MD,FAAFP on a site named Freedom's Run Training. Training at just below the aerobic threshold helps you to build a bigger "engine." Calculating your aerobic threshold is extremely easy. Take the number 180 and subtract your age. That's basically it. You can add a few beats if you have a high level of fitness, or subtract a few if you are just getting back into it, but 180 minus your age is the key.
|Not a recovery sandal . . . a mitochondria!|
During running, the goal is to keep your heart rate below that threshold at all times, as you train your body to convert fat energy more efficiently. As the body becomes better at doing this, you will see an increase in your pace at the same heart rate. After several weeks (3-4 months really), the difference should be quite noticeable. The key to tracking your improvement is by doing a Maffetone test. Basically, you select a consistent run (flat course, track, or treadmill is best) and run 5 miles at just below the threshold pace. This test is repeated every month or two and you can see the difference in the pace.
Unfortunately, I didn't perform this test correctly a month ago when I tried it. Instead, I ran at closer to my Lactate Threshold pace. It was still pretty interesting to watch my pace drop over the course of 4 miles while maintaining a heart rate of about 160 bpm. However, I will be redoing this test in the next week or two so that I have an accurate baseline to measure progress.
Training with the Maffetone method is extremely hard for reasons that are the opposite of what you might think. It's not "hard" in the traditional sense of the word. In fact it's quite easy because it takes place at such a low rate of exertion. But this can be extremely frustrating, like today when I had to stop and walk a couple of times because my heart rate was starting to rise. In a couple of weeks, I have the Rock Canyon half-marathon, and I shutter to think how long it will take me to run it this year (Last year I ran it in a snowstorm in 1:42:58). I'm anticipating at least another hour this year.
Despite the current "slowness" of training right now, I'm going to stick with it through the winter. Since I'm already about a month in, I figure I will continue to train this way through February with a monthly test.