Wednesday, 4 March 2015

Training Zones for the novice (like me!)

My running times from 400m all the way up to 10K have improved since I started "Zone Training"
(times on graphs are my PRs in seconds, using data from my Strava profile)
Week 3 is when I started running again, after about a 15 year break, and by Week 4 I am increasing the distances.
Week 7 was a milestone, being the first 10K I have run in 30 years!
But just look how those times have improved in Week 10!

Heart rate monitors for sports tend to have adverts that go on about training zones.

In order to use them, you need to enter your maximum heart rate.
So, how does a chap like me know what my maximum heart rate is?

The BEST way is to take a maximum heart rate test is in a suitably equipped medical lab with a physician on hand.
Or, if you can't do that, exercise at a high intensity until your lungs are practically bursting, and use a chest-strap heart rate monitor (HRM) to record your activity so you can see the highest reading. It was on that hill where you nearly blacked out. The third hill of that set of three. You know it was.
Various online postings give various warm up methods, and they are worth what you make of them. Nver going to be as good as a "proper" test, and without the physician on hand, are you SURE you are not overloading your heart just to get a number?
Given that some folks have am unfortunate habit of dying while doing something as simple (but potentially intense) as snow-shovelling, if you are a bit unfit, do you REALLY want to see just how fast your heart can go WITHOUT a physician keeping an eye on your ECG readings?

What about if you don't have a HRM?
You could try thrashing along and stopping and taking your pulse the "old" way - 15 seconds on the watch, multiplied by 4. The way medical folks used to do it before they had all the gadgets.
Except, unless there is something wrong with you, your pulse will start to drop very shortly after you stop to check it. If it doesn't drop by 12 beats per minute in the first minute, you'd better have a good reason why it doesn't!
The same caveats apply about overloading your heart without a physician present, though!

What about if you don't want to go flat out, because, like me, you are taking it easy, but still want to do a bit of modest training?
Are there any "ready reckoners" that give an approximate value?

Yep, you bet there are.

Perhaps the "grandaddy" of them all is the formula of "220 - age". Apparently that one dates back to Drs. Haskell and Fox in about 1970, according to the New York Times I got a cycle training book out from the local public library, published in 2011, and the "220 - age" formula is the one the book uses.
Amazon want 18 quid just for the "Kindle" edition - some cyclists clearly have money to burn! (and the price is just one of the reasons why public libraries are just so great!)

And what about the "Dr Seals" and his alternative, allegedly better, method of estimation that the NY Times mentions?
That'll be the "Tanaka, Monahan and Seals" paper from 2001, which gives the formula of 208 - (0.7 x age), with the conclusion that the "220-age" "standard" formula underestimates for healthy. older cyclists. There is a nice plot so you can see how the data actuall spreads out from the "trend" line.
Over 500 folks tested, about half men, and about half women, with about half athletic and half "sedentary". All in all, worth a read!

Want a nice "meta analysis", where someone has sat down and statistically combined the results of lots of studies and formulas, to come up with one "overall" conclusion?
How about this one from 2002, by Robergs and Landwehr.
They conclude that subjects have a pretty wide range of maximum heart rates, and they best that one can get "on paper" is to be within about 6 or 7 beats of anyone who is not very abnormal.
Anyway, they go with the formula of 205.8 - (0.685 x age) plus or minus 6.4 beats. They also suggest that no "paper" formula for maximum heart rate is good enough to accurately predict VO2 (max) from.

Want a nice complicated formula for maths "nerds"?
How about this one from Wohlfart and Farazdaghi (2003):
203.7/1+(e^(0.033 x (age - 104.3)))
If you can't even work out how to calculate that one on your calculator, then don't worry: for me (aged 50) it comes out in a similar range to the other numbers (see below)!
Also, there is a 10% margin of error.

I'm 50 years old, so we have:
220 - 50 = 170 bpm (Haskell and Fox)
208 - (0.7 x 50) = 173 bpm (Tanaka, Monahan, and Seals).
205.8 - (0.685 x 50) = 171.55 - ish bpm, but likely within the range of  about 165 to 178 bpm (Robergs and Landwehr)
203.7/1+(e^(0.033 x (50 - 104.3))) = 174 bpm, but 93% likely to be within 157 to 191 bpm. (Wohlfart and Farazdaghi)

Various "standard" models have been formulated to estimate MHR
Note, though that the studies pretty much accept that some folks with have higher or lower maximum heart rates than the average (!)

But lets just assume I am in the "normal" sort of central band, give or take.
Certainly I've had enough tests in the hospital in the last 6 years to have indicated if there was anything particularly unusual about my heart (!)
I have a slightly slow resting pulse (often in the low 50's, but the lowest I have measured using a store bought "home" pulse and blood pressure meter, of a fairly reputable make, is 48 bpm.
But apart from that, not much to say.

So now I have my estimated pulse of about 173/174, what can I do with it?

Well, folks like to train in "Zones" based on heart rate as a percentage of maximum heart rate.

One typical scheme (lifted from the book I mentioned earlier) goes like this
Zone 1 (the easy one) from resting pulse to 65% max heart rate
Zone 2 66-80%
Zone 3 81-90%
Zone 4 91%+
Zone 5 flat out for 20 secs max.

(btw, the book has the, apparently compulsory, celebrity endorsement)
For an explanation of Strava's zone system which is quite different,
see below (the 8th March update, about a page or so further down)

So dialing my "numbers" in (using a MHR of 174 bpm) gives:
Zone 1 - 50 bpm to 113 bpm
Zone 2 - 114 bpm to 139 bpm
Zone 3 - 140 bpm to 156 bpm
Zone 4 - 157 bpm plus
Zone 5 - brief (20s) absolute maximum power sprint.

But what about the variability in the numbers?
What if I am, say, at the lower end of the large metastudy that gives 165 to 178 bpm? (the Robergs and Landwehr calculation)
So lets say I am really only 165 bpm.
How does that affect the figures?
Zone 1 - 50 bpm to 99 bpm
Zone 2 - 100 bpm to 132 bpm
Zone 3 - 133 bpm to 148 bpm
Zone 4 - 149 bpm plus.

But what if I am the "high" end of the variability, not the low?
What if my "true" max heart rate is more like 178 bpm?

Zone 1 - 50 to 116 bpm
Zone 2 - 117 bpm to 142 bpm
Zone 3 - 143 bpm to 160 bpm
Zone 4 - 161 bpm plus.

Bring those together give the range:
Zone 1 - 50 bpm to 99 bpm
Not sure if Zone 1 or Zone 2 - 100 bpm to 116 bpm
Zone 2 - 117 bpm to 132 bpm
Not sure if Zone 2 or Zone 3 - 133 bpm to 142 bpm
Zone 3 - 143 bpm to 148 bpm
Not sure if Zone 3 or Zone 4 - 149 bpm to 160 bpm
Zone 4 - 161 bpm to 165 bpm
Not sure if in Zone 4 or risking heart damage - 166 bpm plus.

So what conclusions can we draw WITHOUT a properly conducted scientific test on ourselves in the lab?
Well, we are pretty sure that a heart rate of under 100 is in Zone one, and we are eaually sure about the 120-ish to 130-ish band being in Zone 2. Our certainty of Zone 3 is a fairly narrow band at about 145 bpm.

But wait!
Portable heart rate monitors have only been around for 30 or 35 years, while competitive cycling has been around for more than 100!
What did folks do before that?
Are there any PHYSICAL signs other than heart rate that would indicate what training "Zone" we are in for a given level of work rate?
Well, the book suggests that there are:
Level 1 - easy, gentle cycling, can speak easily.
Level 2 - Being able to speak fairly easily but having to put in extra effort, to sentences being broken up into short sections.
Level 3 - Difficult to speak - the pace you could keep up for 20 to 30 minutes, but at a push, just about make 1 hour, but only just.
Level 4 - Unable to speak - the best speed you could do for 3 to 5 minutes before having to slow down
Level 5 - Sort, flat out sprint for 20 seconds, then you'll have to back off a lot (think like a 100 or 200 metres sprinter!)

So it seems like a good idea to cross-calibrate your "paper" numbers with the physical effects the workload is having.
If you are chatting away nicely, you ARE NOT in Zone 3, whatever your HRM and training manual might suggest (!) You have made an error in your maximum heart rate assumptions/tests, or you are using a different system of Zones that the 5-Zone system I have outlibned above (!!!)

Using the "cross-calibration" you are likely to be able to reduce the variation in your "band" of possible "true" maximum heart rate. Are you at the top end of "normal", or the "bottom" end?
Are you even IN "normal"?

So, what about me?

Not owning a chest HRM, I went out jogging with my watch on the inside of my wrist.
I did 3 laps (1.8km - 1.1 miles each). I stopped briefly and manually measured my pulse (the old way, mentioned above). Yes, I was the "loonie" muttering to myself while running, seeing how easily I could speak (!)

O got a pulse reading of about 125, so I added a bit for the "fumble time" (I'm not always that good at locating my pulse!), because, as we know, a "healthy" individual should have a pulse that drops by at least 12 bpm in 1 minute (it is supposed to drop by at least 43 bpm in 2 minutes of rest!),a nd came up with an "adjusted" figure of 130 bpm. A bit of guesswork, but not just a random guess (!)
Next lap I got the dame number, and made the same addition.
Third lap (which I ran a bit faster than the other two (!), I measured 140 bpm (that is, 35 beats in the 15 second measurement interval). I left that one as it was, as I did less fumbling, so my pulse had less time to drop before I measured it!

So how did the "physical signs" measure up?
Well, for the pulse reading which I estimated to be 130 (see methodology in the paragraph above!), I had some trouble speaking while running, only managed sets of about six or seven words or so. Which seems to put my "130" estimate well into Zone 2.
For the last lap, I was down to two or three words - I could count "one two three" out loud, but then that was it - I had to breathe. This seems to me to be breaking into Zone 3, but certainly not near the top of it (!)

So, "my" 130 bpm feels to be in "my" in mid-Zone 2, and "my" 140 bpm feels like somewhere in "my" Zone 2 to Zone 3 boundary.

Looking at the numbers I calculated above for a maximum heart rate of 165 bpm, Zone 2 is from 100 bpm to 132 bpm. That isn't right for me (!) Running with a bpm of 130, it wasn't THAT hard to speak.

How about the "high" end, with a max heart rate at 178 bpm?
Zone 2 comes out (as above) as 117 to 142 bpm.
That sounds more likely (!)

How about the "mid" scale, using 174 bpm?
That gives a range of 114 to 139 bpm.
Well, that could be it, too.

I guess my max heart rate (for Zone calculation) is likely to be in the 174 to 178 range, then.
So "my" Zones are likely to be:
Zone 1 - 50 to 113 bpm
Zone 1 or 2 - 114 to 116 bpm
Zone 2 - 117 to 139 bpm
Zone 2 or 3 - 140 bpm to 142 bpm
Zone 3 - 143 bpm to 156 bpm
Zone 3 or 4 - 157 to 160
Zone 4 - 161 plus
And, to be honest, that is a LOT better than before I did the "physical" cross-calibration.
There are only 3 or 4 bpm in each "vague" zone, rather than the 9 to 16 I had just using the "paper" exercise.
So it looks like I have done all I can without a "formal" test!

My MHR appears to be a bit higher than the central value for most models
So, to conclude, it seems to be a good idea to cross-calibrate the "physical" effects of the training Zones you are using with the expected pulse readings.

Bet this post will draw some comments (!)


Update 6th March 2015: the Heart Rate Reserve Method
It has been brought to my attention that there is another way of calculating where the training "zones" start and finish - the "Heart Rate Reserve" (HRR) method.
Polar, the maker of sport training devices attribute this method to Karvonen., an online medical resource, also favour the HRR method.

So lets run some numbers into the HRR formulas.

I am fairly happy that my "true" maximum heart rate is about 175 bpm. It is close to what ALL of the "theory" models predict as a "central" value for someone of my age, and also "cross-calibrates" well with the ACTUAL perceived work rate (see above).

So let's take my resting heart rate as 50-ish (I have measured it in this sort of range on multiple occasions).

Exercise HR = % of target intensity (HRmax – HRrest) + HRrest

 On the subject of intensity levels, every source varies (!), but there seem to be some general agreement that about 60% intensity is the bottom of the "Zone 2" I outlined above, and that the "Zone 2/3" boundary at the top of "Zone 2" is at about 80% (sources seem to vary between 75 and 85%!).

So, my max heart rate is 175, my resting heart rate is 50, and we will look for the 60% intensity "exercise" heart rate (EHR)
EHR = (0.6 (175-50))+50 = (0.6 x 125)+50 = 75 +50 = 125 bpm.

And now for the 80% EHR
EHR = (0.8 (175-50))+50 = (0.8 x 125)+50 = 100 +50 = 150 bpm.

With the "original method" I used above, the bottom and top of Zone 2 were at 66% and 80% of max HR
Bottom of Zone 2 = 66% x 175 = 115 bpm
Top of Zone 2 = 140 bpm.

So the numbers come out a little higher with the "Heart Rate Reserve" method.

But what's this ... has a LOWER "intensity" as the bottom of "their" zone (!), as well as a  "physical" method of testing as well as the "numbers" method.
They use only 50%, which would give the Bottom of Zone 2 as just 112.5bpm - pretty similar to the 115 bpm I calculated earlier.
And their "physical" sign that you are working hard enough to be in Zone 2 (which they call the "aerobic zone"? - why it is simply that you should be "warm and slightly out of breath". That sounds rather like the "physical sign" I mentioned above - being out of breath enough to affect your speech WHILE exercising (WHILE, note, not afterwards!).

So why would some sources recommend higher numbers than others?
Well, the extra intensity would result in a more intense workout, and no doubt bigger benefits.
But the danger for us novices is "overdoing it" - too many folks just don't pace themselves properly, and don't take proper "rest" periods, instead, their enthusiasm keeps them going until theu injure themselves. "Better", more "experienced" athletes already know all this, and allow for it.

For someone starting out on exercise from a low-ish fitness base (like me!), perhaps the lower limits are more appropriate for now, despite the benefits from exercising at a slighlty higher pace.

Of course, using Polar's method of Maximum Heart Rate (220-age = only 170 bpm for me, not 175 bpm!)), rather than my own "cross-calibrated" method, gives lower top-and-bottom limits for the "Aerobic" region/"Zone 2" anyway, and using Polar's methodology throughout gives that zone covering 122 bpm to 146 bpm (3 less at the bottom, and 4 less at the top), which puts it just 4 to 6% above the zone I was using - so almost all of my "Zone 2" will overlap almost all of Polar's "Aerobic" region anyway!

Update 8th March 2015: Strava's DIFFERENT zones

Strava has "zones", too.
They are used for the "suffer" score, amongst other things.
Lets have a look at them.

In the "Zone" system I outlined above, that came from the training book I am reading, we had

Zone 1 (the easy one) from resting pulse to 65% max heart rate
Zone 2 66-80%
Zone 3 81-90%
Zone 4 91%+
Zone 5 flat out for 20 secs max.

I will call them the "Cyclosportive" zones, after the name of the book.

the book also gives some descriptions of what the rates the upper "Cyclosportive" zones represent:
Zone 3 - one hour time - you could just about manage an hour at this rate, then you'd have to slow down.
Zone 4 - three to five minute "sprint time", after 5 minutes max, you'd have to slow.
Zone 5 - flat out for 20 seconds.

So turning these into real-life situationsm if you're spending 5 minutes at a time in "Cyclosportive" Zone 5, you have either vastly miscalculated your maximum heart rate, or you are using a DIFFERENT "Zone" system.

Same is true if you are spending 30 minutes in "Cyclosportive"Zone 4.
That's Zone THREE
in the "Cyclosportive" system, not Zone 4!!!

Of course, you can "hack" the numbers by deliberately using the wrong figures for maximum heart rate and/or resting heart rate - quoting too low a Max heart rate makes all your training zones "easier" - good for "bragging rights", but it undermines the "training" element.
So why ARE you training?
To impress your friends?
Or to get fitter/faster?

So lets have a look at a very fit Strava rider:
Laurens ten Dam, the TdF rider.
Strava have used one of his Strava outputs in their "blog".

Strava has listed 5 of their zones against his ride.
They have also said that he has a Maximum Heart Rate on 196 bpm (he's 16 years younger than me!), which is pretty certain to have been "professionally" tested in a lab with all the fancy machines etc. etc.
Anyway, His Strava "zones" are
Z1 "Endurance" 0-115 bpm
Z2 "Moderate" 115-152 bpm
Z3 "Tempo" 152-170 bpm
Z4 "Threshold" 170-189 bpm
Z5 "Anaerobic" 189 bpm+

So let's get the calculator out, and see what they come out as when compared to maximum heart rate.

Strava Zone 1 - zero to 58.7%
Strava Zone 2 - 58.7% to 77.6%
Strava Zone 3 - 77.6% to 86.7%
Strava Zone 4 - 86.7% to 96.4%
Strava Zone 5 - 96.4% +

Let's remind ourselves what the "Cyclosportive" zones are:
Cyclosportive Zone 1 (the easy one) from resting pulse to 65% max heart rate
Cyclosportive Zone 2 66-80%
Cyclosportive Zone 3 81-90%
Cyclosportive Zone 4 91%+
Cyclosportive Zone 5 flat out for 20 secs max.

So Strava Zone 2 is a bit easier than Cyclosportive Zone 2, especially at the lower end (!). No doubt this appeals to "bragging rights" cyclists! There is only 2.4% difference in %MHR (percentage of Maximum Heart Rate) at the top of the Zones, but the Strava system is a full 6.3% easier at the bottom of the zone (!!!) That 6.3% shortfall is a LOT!

Let's look at the "Zone 3" numbers.
Strava Zone 3 is, again, a bit easier than the Cyclosportive Zone 3. At the bottom (the "easy" end) the numbers are 3.4% of %MHR less, and at the top they are 3.3% less! So Strava Zone 3 is about 3.3% of %MHR easier!

Strava Zone 4 follows the same pattern. Strava Zone 4 is 4.3% easier at the "bottom" of the range, and 3.6% easier at the "top". Again the Strava "zone" system is "easier" than the one I am using.

The Cyclosportive Zones only use Zone 5 as a "short sprint" zone, while for Strava it is a proper "top" zone. Yet again, the Strava "zone" system is "easier" than the one I am using.Polar also have what they call "Polar Sport Zones" (based on MHR, Not HRR like their other system), and my, they are a LOT easier than either the Strava Power Zones or the Cyclosportive Zones.

Different training systems use different rates for their "Zones"
Throw in a simple formula like 220-age for Maximum Heart Rate (which, on my cross-calibration calculations above, underestimates my MHR by 4 to 8 bpm!! - that can make the difference between the top of Strava Zone 3 and the MIDDLE of Strava Zone 4), and I'd look a lot fitter if I used the Strava system! The Polar system is even worse, it just assumes that I have a MHR of 170bpm (which I don't!).
Why do companies have "easy" zones?
"Bragging rights" driving sales?
Easier for the unfit (like me!)?
But training too "softly" doesn't get me anywhere much - I wouldn't BE any fitter, it is just the data would make me APPEAR fitter (!)

So, in actual training, what difference does it make?
Well, if you are trying to impress your friends, the Strava system is clearly better/easier for that particularly if you underestimate your MHR.
Of course, "Premium" Strava members can apparently adjust the zones to suit themselves, so the "braggers" can make things even easier, while the "trainers" can make the zone's better fit their needs. Another example of how Strava CAN be a serious training tool if taken seriously, but they recognise that a good part of their income will come from the "bragger" end of the market.
Polar Sport Zones are even worse!

But if you are trying to actually get fit, then you are only "cheating" yourself by making things too easy.One last thing.
Lets have another look at the "pro" rider - Laurens ten Daum.
On a hard ride (7500 calories burnt!) taking a bit more than 5 hours (!), let's see how long he spent in each Strava "zone".
Strava Zone 1: 17%
Strava Zone 2: 39%
Strava Zone 3: 42%
Strava Zone 4: 2%
Strava Zone 5: 0.

Yep, a TdF rider that didn't even get into Strava Zone 5.

If YOU are spending most of your time in Zones 4 and 5, and you are not just "short sprint-rest-short sprint" interval training, then your set-up is wrong - eiter you've entered too low a Maximum Heart Rate, you've fiddled with the "custom" zone settings (available to Strava "premium" members), or you want to get a better HRM measurement device!

Update 2, 8th March 2015:A quick poke around on Strava's "Zen desk" help to explain how Strava Zones are calculated.

The Strava "Zones", which they call "Power Zones" are based on a percentage of the riders "one-hour-power". That, for the Cyclosportive book is what they use as a definition for their "Zone 3" band. Strava makes it quite clear that this same concept is the basis of their "Zone 4" band.
Indeed, the definition of "Cyclosportive" Zone FIVE is the same as the definition of Strava Zone SEVEN (!)

For running, Strava use 6 Zones (they look like the cycling zones with the top one lopped off - no good for Usain Bolt, then!), and again, the definition of Strava Zone 4 is the same as the Cyclosportive Zone 3 - the one-hour rate.

So, for me, how does the "calibration" run I did above measure up to Laurens ten Dam's Strava Zones?
Well, I had numbers that were 130 bpm and 140 bpm, and I calculated that my MHR is about 175 bpm (I am 16 years older than Laurens ten Dam, remember!),
130/175 = 74.3%, while 140/175 = 80%
Like I said before, the "middle" and "top" of Cyclossportive Zone 2.
On the Strava "system", my "middle" Cyclosportive Zone 2 becomes near the top of Strava Zone 2, and my "top" of Cyclosportive Zone 2 becomes almost a third of the way into Strava Zone 3 (!)
Whether you choose to divide you training zone into 5, 6, or 7 (or even more) bands/zones) doesn't really matter. But when comparing one "system" with another, be careful you are not comparing oranges to apples!

Update 17th March 2015:
I am attempting to include British Cycling's training zones in my comparison as well.
Problem is that they like to measure things by "Functional threshold heart rate" (FTHR) rather than by maximum heart rate (MHR).
As "their" scale goes up to 121% of FTHR, I have attempted to approximate these to MHR by dividing each band by 1.21 (clearly, a rider should NOT be going over 100% MHR, and if you can without permanent damage, then you are using the wrong (too low!!!) value for MHR!!!)

Some of the British Cycling "zones" look a little low in the comparison, though ...
What do you think?

A first attempt to compare the British Cycling "zones" with the other methods.
As the British Cycling zones use FTHR on a scale going up to 121%, rather than MaxHR,
I have divided each of the British Cycling numbers by 1.21
Update 2nd April 2015:
Now in possession of a Heart Rate Monitor, I have been performing a few calibration tests with it:
Test 1
Test 2
Test 3
Test 4

I was a bit doubtful about the readings on test 4, as they seems a bit high, but the other three tests all produced reasonable numbers.
So I guess my HRmax is higher than I thought.
From tonight, I am going to assume it is more like 181 bpm (the highest number I got on Test 4), so that will alter my "Cyclosportive" training zones to:
Zone 1 - 48 bpm to 117 bpm (up from 113 bpm) - "recovery/weight control"
Zone 2 - 114 bpm to 144 bpm (up from 139 bpm) - "two hour power" - aka "endurance"
Zone 3 - 140 bpm to 163 bpm (up from 156 bpm) - "one hour power"
Zone 4 - 164 bpm plus (up from 157 bpm) - VO2 max - "3 to 5 minute power"
Zone 5 - brief (20s) absolute maximum power sprint.

So, ia a man of 50 likely to have a HRmax of 181?
It is a bit high on the evaluations of most of the folks I mentioned near the top of the post, but Wohlfart and Farazdaghi's work suggests that 93% of 50 year-old men would fall in the range 157 to 191 bpm, and 181 falls clearly in that range.
So I could have a higher HRmax than "average", and still be "normal".
So I will go with that for the time being.
Must update my HR on Strava to my "new" figure of 181!

Just goes to show how far out some of the simpler "apps" and runners watches are - some of them still use the 220-age formula, and that would give me a HRmax a whole 11bpm lower (and more importantly, I could fool myself into thinking that I am training much harder than I actually am!!!).
Huge "Suffer Scores" resulting from using a rather low HRmax appeal to some, but achieve little in the way of "real-world" progress.


  1. Pretty short blog. Thank you
    Sandy recent posted
    Aerobic Exercise Examples

  2. I go for jogging (both "road" and "cross-country"), walking, outdoor cycling (not mentioned!), and cycle turbo-trainer (I have a Tacx turbo trainer, mentioned elsewhere on my blog - indeed I have had it for more than 3 years now).
    Skipping? - thought about it, but at about 6 foot 3 (1m90) tall, rope length is the catch.
    Swimming - as I have gotten older, I seem to have developed an aversion to water that isn't rather warm ;-)
    My turbo trainer is a bit like using a stationary bicycle - except it uses a normal bike - so it fits me rather well ;-)