It's been about six months since I began devoting at least 90% of my training to low heart rate, fat burning training. In contrast to how I felt when I was exercising with higher exertion (granted, while also drinking heavily and eating unhealthily), I have more energy now, my form is better, exercise is far more enjoyable, I'm leaner, and I am now much faster.
In case more evidence is needed to support this, I decided to do another MAF (maximum aerobic function) test this past Tuesday. The MAF test is performed by running at your target aerobic heart rate for a few miles on a flat course and recording each mile pace. The result is then compared to previous months.
It has been a few months since I've tested my pace, since I had some injuries from a couple of bike accidents which I thought had slowed me down, and I didn't want to discourage myself. However, yesterday I was pleasantly surprised by the results:
As you can see, at my aerobic heart rate of 142 (the same heart rate I've been sticking to for the last few months), my pace has improved dramatically. I have posted my first miles under 8 minutes ever. Even when I was exercising at high exertion, I was never able to consistently stay below 8 min/mile over multiple miles. Here I have done it through 5, with more in the tank to run farther and faster if necessary. I'll say again, running at this pace is easy because I am doing so at a low heart rate.
The patience and humility from a few months ago have paid off, and I can say with absolute confidence that this type of training is highly effective. I will reemphasize the need for patience. For this to work, it is vital to have patience at the beginning when the pace is painfully slow, and patience throughout the course of training when you hit a variety of plateaus that seem never ending. Eventually, with enough persistence, you will break through the plateaus.