Maffetone 180-formula and HRM-based treadmill training

Since I've started using the Maffetone Method for training, I've run exclusively on a treadmill; specifically, a Life Fitness T3-5. I've had it in my house for five years, and I really like it. It works very well with the Maffetone Method, since my pace can be controlled via heart rate.

I've recently changed my routine just a bit, for three reasons:

1. I haven't been following Maffetone's 180-formula, and I'd like to get closer to it.
2. The way the Life Fitness heart rate control works puts me even farther away from the 180-formula. It allows me to go 3 or 4 beats per minute faster than my set target without slowing me down; this happens often near the end of longer runs.
3. Although when I started I was skeptical of the practicality of 180-formula for me personally, the improvements in my maximum aerobic function surely allow me to run at a much lower heart rate than when I started.

In short, I've targeted a heart rate of 138 beats per minute, compared with the 180-formula's 127; the Life Fitness treadmill bumps me up even more to about 141 or 142; and my improved fitness will now allow me to run at a lower heart rate.

Between 12 Feb and 22 March, my pace at 138 beats per minute dropped by about 58 seconds per kilometer (just over 1 1/2 minutes per mile). The main reason I didn't use the 180-formula to begin with was that my pace at 127 beats per minute would have been very slow; almost a walk. It probably would have been a walk at the end of an hour, although I admit that I didn't actually try it.

Rather than abruptly change from 138 bpm to 127 bpm, I'm doing it gradually. Before I was keeping my heart rate at 138, but bumping up my speed once I had been able to maintain a given pace for two days. I'll continue to do that; but I'll also drop my target heart rate by 1 bpm as well.

This has slowed my pace progress a little; I'd been speeding up every two days like clockwork for more than two weeks. My last two up-ticks in pace, along with a down-tick in heart rate, have both required more than two days to maintain. I'm currently at 136 beats per minute. I don't know if I'll ever get all the way down to 127. Before I get there, I'll probably have moved from Maffetone's category B ("inconsistent [training] or are just getting back into training") to category C ("training consistently"), which will move my target up 5 beats per minute.

Maffetone Method

For about a month, I've been training using principles of the Maffetone Method. I mentioned this indirectly; at the time, though I knew a little of Dr. Maffetone, I really hadn't read much of his work.

That didn't stop me from jumping in and start using the one part of his method that I knew -- at least, I nearly used it. I fudged a little.

You can read about it on his web site. In particular, here's a page describing how to pick an appropriate heart rate for training. He dismisses the usual "220-age" formula that you may have seen, and has his own formula. It is mainly based on age, but makes some adjustments for health and fitness. What it does not adjust for, which seems strange to me, is the rather wide variation in maximum heart rate. My own max rate, for example, is fairly high for my age. I haven't done a max test in a number of years, but during a not particularly hard run just this month, I hit 186 beats per minute. I'm sure my actual max is at least a little above that. In past years, I've measured my heart rate at over 200.

All of this suggests to me that my own heart rate range is probably about 20 beats per minute higher than the mean for my age. I'm 48.

Using Maffetone's 180-formula, I get to 127 beats per minute. I can hit that at a walking pace.

Using Mark Allen's slight variation I get to 132 beats per minute. Let's say a moderately brisk walking pace.

I'm no expert, but neither of those seemed like a reasonable benchmark.

I did a little experimenting on the treadmill, and found that I could keep a slow run going at 138 beats per minute, so that's what I've been using.

Here's my routine: I run every day (though I skipped 5 days when I had a viral infection and couldn't run without falling off the treadmill in a coughing fit). My minimum run is 30 minutes, and my maximum is 60. Each day I pick the duration mostly by how I feel and how much time I have available. I hope to get a bit more structure as I progress, and also do some longer runs, but as of now, this is what I'm doing.

I started with a pace that I guessed would be close to the fastest I could manage at a heart rate of 138 beats per minuted. I have a treadmill that will adjust both incline and pace based on heart rate, so each day I just set that up and run. I think my guess was reasonably close. The first seven days I just stayed at that same pace, and the treadmill didn't have to slow me down because my HR went up. On the eighth day I bumped up my pace a tick (i.e., by 0.1 km/hr), and that day I did have to slow down to maintain my target rate.

My original idea was that if I could maintain a given pace all the way through for three days in a row, and keep my heart rate at my target, I would speed up another tick. I kept this up for a couple weeks, and the only times the treadmill program slowed me down were the one I mentioned before (the eighth day), and just after I took those five days off from being sick.

After that, I've never had to slow down, so about a week ago I decided that just two days in a row with no slow-down would be my new standard for picking up the pace. Tomorrow I'm set to go up another tick; that'll be four times in a row on a two-day schedule.

Every run is at a comfortable pace. I'm never pushing myself really hard, and as a result, I'm never dreading a run, and I'm never spent at the end.

But here's the thing: after just over a month (minus sick days), I find myself running each kilometer more than 37 seconds faster than when I started, but my heart rate is the same. In standard (i.e., non-metric) terms, I've dropped just over a minute per mile.

This is all predicted by Dr. Maffetone. He says don't kill yourself. "No Pain, No Gain" is for chumps. You don't have to injure yourself, or be tired all the time, to improve.

I'm part-way through one of Maffetone's books. and it's already changed how I'm going to proceed. I said about a week ago that I was soon going to incorporate some intervals. I've changed my mind. Part of the reason is what I've read (he says to build your aerobic base at a low heart rate for three to six months), but mostly I've just looked at my results so far, and thought about it.

Why change something that's working so well?

Science Friday: exercise and DNA

A segment on Science Friday discussed the effect of exercise on DNA. The headline is a little misleading -- DNA itself is not changed; rather, DNA methylation changes. Says Dr. Juleen Zierath:

[W]e found that 35 minutes of high-intensity exercise was sufficient to have a removal of these methyl groups from the DNA and a production of proteins which would support the metabolism of sugar and fat after exercise. So it's not just to exercise. In this case, you needed to do an exercise bout which would be at the level of where you might not be able to comfortably talk if you're running with a running partner. It's not like walking. Running or biking at a level of exertion where it's hard to carry on a conversation for about 35 minutes.

I've been deliberately avoiding high-intensity running lately, but I'm about to introduce some interval training in the next week or two. I have nine weeks until my half marathon.