The main purpose of this post is to make explicit something that has been implicit in some of my recent posts, that the definition of heart rate training zones I have been using has changed recently. What are heart rate zones? Very briefly, the faster I ride, the higher my heart rate, making heart rate a measure of the Intensity of my rides. Coaches want their athletes to train at a range of different Intensities, with a specific amount of time spent at each Intensity. Traditionally, the continuous range of Intensities is divided up into zones, for example, 130 to 140 heart beats per minute (bpm) equals Zone 2, 140 to 150 equals Zone 3, etc. Different coaches have different zone definitions. Furthermore, zone definitions are athlete specific as well. Coaches define heart rate zones as percentages of the athletes maximum heart rate or anaerobic threshold heart rate, for example. I am estimating my maximum heart rate as 180 bpm and my anaerobic threshold heart rate as 160 bpm and all the heart rate numbers in this post are relative to those estimates. Thus, nobody but me should use the heart rate bpm values in this post unless their maximum and anaerobic threshold heart rates are the same as mine.
When I first got my Garmin Heart Rate monitor back in 2012, I started using a set of zones which were fairly similar to those recommended by Coach Joe Friel, my favorite coach of the time and, mostly due to inertia, continued to use those zones until fairly recently. Those are the zones named Zombie Zones in the chart at the top of this post. Way back in January of 2019 I reviewed the eBook by Coach John Hughes, “Intensity Training for Cyclists” and noted that the training zones in this book were different from what I had been using. For a variety of reasons, some of which I will discuss below, I did not act on that observation immediately but I did think about it and now, four years later, those are the zones I am using. In the chart at the top of this post, these zones are named Hughes Zones.
The context in which I first looked at the Hughes zones was the preparation of my post, Deconstructing 100K per month. In that post, I was attempting to map the mixed-zone riding I was doing in the hills of California, my Alpine ride, to the training plan given in “Distance Cycling” by John Hughes and Dan Kehlenbach. For that analysis, I continued to use my old Zombie Zones, and using those zones, came up with the amount of time spent in each zone shown in the chart at the top of the post. Using those zone distributions I concluded that my Alpine ride gave a mix of Zone 2 and Zone 3 which was a good match for the training plan I was using from Hughes and Kehlenbach. But as I continued to think about the Hughes book, I started to wonder how those distributions would change if I had used the Hughes zones, and as is shown in that chart, they changed significantly. Using the Hughes zone distributions, the Alpine ride provided much more Zone 3 riding and much less Zone 2 riding than the plan I was trying to approximate. But which of those two zone systems is the proper one to use? As of today, my thinking is neither of them. The Hughes and Kehlenbach book contains a third set of zone definitions that lie somewhere between the Zombie Zones and the Hughes Zones. A principle I have come up with is that there is probably some interplay between the different zone systems used by different coaches and their training recommendations such that one should be consistent about using the zones and recommendations from the same coach. So, if the goal of this post were to revise my 100K plan (which it is not) I would do so using the Hughes and Kehlenbach zones. But if that revision is not the goal of this post, what is, and how did I end up selecting the Hughes zones?
Over the years, I had collected about a dozen different zone definitions. One reason I didn’t immediately switch to the Hughes zones when I first came across them in 2019 was that it was not obvious why I should select these zones as opposed to any of the others. Since then, there have been three significant changes that have affected my training. The first is my move into a home in a hillier neighborhood, a change that I believe resulted in overtraining, chronic fatigue, and poor performance. The second, a response to the first, is that I have resumed using a heart rate monitor after riding without one for five years. The third has been an evolution in my thinking about training. My current training is based on my personal experience combined with a personalized application of ideas of Coach John Hughes. Given this evolution, rather than trying to adapt training plans from Hughes and Kehlenbach to the hills in which I ride, I am more likely to invent training plans based on the ideas of Coach Hughes. Thus, in order to be consistent, I have adopted the Hughes Zones.
I’d like to introduce one last complication before ending. When it comes to riding for health, although I certainly listen to Coach John Hughes, there are a set of recommendations from the medical community to which I give priority, their advice to engage in at least 150 minutes and ideally 300 minutes of Moderate Intensity aerobic exercise or at least 75 minutes and ideally 150 minutes of Vigorous Intensity aerobic exercise a week, in any combination. That is, 200 minutes of Moderate Intensity combined with 50 minutes of Vigorous Intensity exercise in a week counts as meeting the ideal recommendation. But what counts as Moderate or Vigorous Intensity? The Mayo Clinic has provided a definition of these in terms of heart rate; Moderate Intensity (for me) is a heart rate between 90 and 125 bpm and Vigorous Intensity between 126 and 153 bpm. (I have no idea how the medical community would have me count the cycling I do at heart rates above 153 bpm.) Whatever training plans I come up with, I try to make sure that they at least meet the ideal recommendations of the Medical Community. In future posts, I will describe how I am planning on using the new heart rate training zones described in this post to help me design future training plans. Stay tuned.
