This is part 2 of 2.  Which means that if you missed part 1, you are certainly missing out.  There’s probably a hole in your soul that is shaped approximately like this prior post.  Now that you’ve filled that void, you are appropriately prepared to continue.  Wear protection.  (And yes, I am well aware that this is not “next week” from said prior post’s perspective.  I repent.)


Once you’ve got a max heart rate, the rest of heart rate training follows a fairly simple logic.  Work out at different heart rates between resting and max and get different benefits out of the work out.  Fortunately, there’s not quite as many interpretations of zones as there are ways to divine (a.k.a. estimate) max heart rate, but it’s close.

The good news is that they’re all telling you the same thing; just dividing the zones in slightly different places.  What makes this less fishy than it might appear is a reminder that your heart rate is a continuum.  Your body is always metabolizing a mixture of different compounds.  When a zone is described as working your body in a specific way, that is the primary effect that the work out will have on your body, not the only effect.

I’m looking at three different approaches, which are pretty indicative of the three mindsets people have on the matter.

BrianMac, the British webmaster who has compiled information from many different sources, splits heart rate training in to four zones;

  1. 60-70% of Max; the recovery zone
  2. 70-80% of Max; the aerobic zone
  3. 80-90% of Max; the anaerobic zone
  4. 90-100% of Max; the redline zone

Short version: zone 1 builds endurance and burns fat, zone 2 builds cardio aerobic capacity, burns some fat, and should be the target for long runs, zone 3 helps increase your anaerobic threshold (the point at which you can’t convert glycogen to lactic acid any more), and zone 4 is working fast twitch muscle fibers via short interval workouts.

However, unlike most other zone training schemes, these percentages are not a straight percentage of max heart rate, but calculated as a percentage of the difference between your resting heart rate and max heart rate. So we take that magic number (195 for me) and subtract our resting heart rate (58 for me, according to the magical mystery Garmin chest strap), then do the percentages off that number and tack the resting rate back on to get our zone ranges. For me, rounding, this would be;

  1. 140 – 154 bpm
  2. 154 – 167 bpm
  3. 167 – 181 bpm
  4. 181 – 195 bpm

Which seems fairly reasonable.

Most other heart rate training programs take a straight percentage of the max heart rate, avoiding all that messy resting heart rate math.  Sally Edwards‘ program, for example splits in to five zones:

  1. 50-60% of Max; the healthy heart zone
  2. 60-70% of Max; the temperate zone
  3. 70-80% of Max; the aerobic zone
  4. 80-90% of Max; the anaerobic threshold
  5. 90-100% of Max; the redline zone

This is pretty close to BrianMac’s four zones, but with the “healthy heart” zone tacked on the bottom.  This extra zone essentially covers low level exercise where you’re strengthening your heart but not improving your fitness.  Never a bad thing to do, but it’s not going to improve performance if that’s what you’re going for.  After that, Sally’s zones are the same; zone 2, burn about 85% fat, zone 3, improve cardio capacity (burn fat and carbs about equally), zone 4, burn carbs until you can’t process the glycogen any more, and zone 5, that all out effort for the fast twitch fibers.  For me, that’s 97-117 bpm in zone 1, 117-136 bpm in zone 2, 136-156 bpm in zone 3, 156-175 bpm in zone 4, and 175-195 bpm in zone 5.

Way off from BrianMac’s charts.  Wow.  Let’s complicate matters.

Marius Bakken chops things up a little bit differently.  Though he’s not quite as catchy with a clever name for each zone, his divisions come a little bit closer to BrianMac’s magic math.

  1. <70% of Max; easy running
  2. 70-80% of Max; junk miles
  3. 80-87% of Max; anaerobic threshold (optimal training)
  4. 87-90% of Max; pushing the pace
  5. 90-95% of Max; really hard 5k-10k work

Note that he’s not pulling any punches on his description of what everyone else calls aerobic exercise.  He’s presenting this from a single viewpoint; how to improve your endurance running.  If burning fat is a priority for you, then these aren’t junk miles.  If improving performance is your goal, then they are.  Remember, you still burn fat in an anaerobic workout, but at a lesser rate as about half the energy is coming from glycogen stores.  For me, this puts my ranges at sub 136 bpm for zone 1, 136-156 bpm for zone 2, 156-170 bpm for zone 3, 170-175 bpm for zone 4, and 175-185 bpm for zone 5.

I really like the fact that he calls anaerobic training “optimal” training.  In short, this is where the majority of your training should be if you’re trying to increase stamina in the long haul.  According to this approach, at least.  Before I get in to that, a few quick facts;

  • You can’t change your maximum heart rate.  Max heart rate does not improve with fitness.  It’ll decrease with age, which is why all the formulas to estimate it involve some voodoo math involving your age, but unless you’re taking certain heart medications it won’t go up.
  • You can lower your resting heart rate.  Resting heart rate will lower as your improve.  Take the time to measure it periodically – maybe once a month – especially if you’re using BrianMac’s training zones.
  • You can increase your anaerobic threshold.  And need to.  This is what holds you back.  This is “the wall.”  The more time you spend training in the anaerobic zone, pushing this threshold, the more you’re conditioning yourself to be able to stay there longer.  Essentially, you’re teaching your body to provide oxygen longer so you’re not switching to all-glycogen as soon, and then to metabolize glycogen longer so you can continue to maintain that level of effort.

This  is where endurance success dawned on me.  I’m able to maintain my target marathon race pace for a little bit more than a half marathon distance, but simply run out of energy before I reach the finish line.  After posting a recent DailyMile workout, my DM friend Kimberly pointed out that my heart rate was kind of high for the pace I was running.  At first I was kind of defensive, pointing out the math and some of the details from my Garmin TC log that doesn’t import to DailyMile, but when it comes down to it, she was right.  That was exactly the problem.

I spent a majority of that run in the upper end of the anaerobic zones based on BrianMac and Sally Edwards’ charts, and was in the redline zone for Marius Bakken’s.  If running the pace I want to target for 26 miles puts me metabolizing glycogen the whole time, then that’s clearly not going to work.  Workouts at this pace are what I need to do to push that anaerobic threshold and improve my fitness to where this pace becomes an aerobic workout.  While they’re “junk miles” for training, if I can go a whole race in that zone, I’m golden.  Or, rather, should probably push harder (and look for a corporate sponsor…).


I know, too late.

Below 80% of your max heart rate, you’re burning mostly fat and improving your heart health.  Go slow enough and it’s not burning a whole lot of fat, but is great for warmups and cooldowns.

Above 80% of your max heart rate, you’re only getting about half your energy from burning fat.  As your heart rate increases to the point where it can’t process oxygen for aerobic energy, adenosine triphosphate and creatine phosphate give way glycolysis, the process that converts glycogen stores to energy.  Go fast enough and you’re not even really doing that; you’re just depleting what you’ve got.  But while you’re able to maintain this level of effort you are conditioning your body to do it longer.

Throw it All Out The Window

So now that I’ve gone and distilled years of scientific research in to a single threshold (not to insult said research; but I need thing simple for my own benefit), there’s another approach published by TriAthlete Mark Allen, ignoring your max heart rate and taking a reverse approach to conditioning.  Instead of zone training, he simply comes up with a formula to identify your personal max aerobic threshold.

  • 180 – [your age] ± 5 based on experience

Yup, experience.  Essentially, he wants you to subtract 5 bpm if you don’t currently work out, subtract 2-3 if you work out 1-2 times per week, and add 5 bpm if you’ve been working out for more than a year at 7 or more times per week.  Plus 5 bpm if you’re over 55 or under 25, then another 5 on top of that for over 60 or under 20.  That’s 148 for me, just a bit lower than the lower end of the aerobic zones in the other approaches.

What’s important about Allen’s approach, is that he’s telling people to stay in the aerobic zone for most workouts, then return to anaerobic a couple of times a week only when the aerobic training efforts plateau.

I’m sticking with plan A for now, as I’ve been inadvertently taking Allen’s approach up until recently and know damn well that I’ve plateaued.  Essentially, less junk miles, more quality speed workouts, and paying more attention to my heart rate.  Maybe more Cheerios.

What you should find, if you target pace based on heart rate, is that your workouts will fall in to certain pace patterns, similar to the paces recommended by most decent training plans.  Most of these plans base the pace off a recent race pace you provide, which is essentially assuming that your race pace is zone 4/5 and extrapolating from there.  Using heart rate zones instead will help you target paces that will let you improve upon what you’re truly capable of, which may or may not be the pace you ran at a recent race.  (Greg McMillan’s pace estimator1, for example, tells me that based on my 5k PR I should be capable of a 3:09 marathon, something that’s not going to happen unless I can improve my anaerobic threshold to sustain a 7:15 pace for more than 15 miles.)

Next post, definitely some pictures, methinks.

Show 1 footnote

  1. Warning; plays music.