Author Topic: Help with HR zones please - I'm shite at maths  (Read 2793 times)

Help with HR zones please - I'm shite at maths
« on: June 01, 2008, 03:11:38 pm »
I have subscribed to several cycling magazines and what with Cycle and Arrivee - I have several to enjoy.  This makes it tricky sometimes as I am often 'behind' in my reading and can't find the one I want to refer to.
I was reading in Cycling Plus ( if anyone can help me with the issue number - please feel free ) about HR training.  This was basically what Mal introduced me to at the start of the year.
LSD - long slow distances - with the intention of teaching my body to burn fat not carbs.
Back then we talked about not reaching the carb zone and therefore avoiding sugar spikes etc. when I got home and was famished ( in my head ).
I started off working at 120bpm on my commute and tried my best to stick around that area.
Mal had said that after a while I would expect my time to get quicker etc.
I have.  My commute now regularly sits on 130 bpm and this feels very very comfortable.

From reading the article in Cycling Plus and then an article in Arrivee about a chap that weight trained for audax riding - I went out today and tried to find my max HR.

I warmed up really well and after 22 miles came to a decent hill.  I pushed up it hard and got to 170 bpm and then started gulping in lung fulls of air.  After the cafe stop I did a similar big effort on a much lesser ascent and got it to 173 before I felt weird.

Neither is max - as I could still ride afterwards so I am guessing 176 or thereabouts is going to be max.

220 - 40 = 180 so I am not far from that rule of thumb that means nothing in a lot of cases  :P

My resting HR is around 56 I think ( or a bit less ).

So what is my training zone?
So what is 80% of my max?

How do I do the maths please?

Re: Help with HR zones please - I'm shite at maths
« Reply #1 on: June 01, 2008, 03:24:10 pm »
Not telling you!  Durrrr!!!   :P

Re: Help with HR zones please - I'm shite at maths
« Reply #2 on: June 01, 2008, 03:29:04 pm »
Thanks.  I will remember to push you off into a hedge next time  ;D

Re: Help with HR zones please - I'm shite at maths
« Reply #3 on: June 01, 2008, 03:38:06 pm »

Re: Help with HR zones please - I'm shite at maths
« Reply #4 on: June 01, 2008, 03:39:32 pm »
That looks ACE !!  ;D  ;D

hellymedic

  • Just do it!
Re: Help with HR zones please - I'm shite at maths
« Reply #5 on: June 01, 2008, 03:44:41 pm »
I can't remember the calculations either and CBA to look them up.
Basically HR 60 = 0% effort.
180 = 100% effort

Difference is 120

You will burn mostly carbs if your heart rate is with 40 or so of your max.

For LSD work you're best riding at around 130, which is just what you're doing...

road-runner

  • is in Slovakia.
Re: Help with HR zones please - I'm shite at maths
« Reply #6 on: June 01, 2008, 06:39:13 pm »
There are two methods of measuring your heart rate as a percentage of your maximum possible heart rate, referred to as %HRmax for short that are generally used by cyclists.

numbnuts' link is the first one, where you simply divide a particular heart rate by your maximum. Using your maxHR of 176, we can calculate these %HRmax figures for you:
0% = 0 bpm
5% = 9 bpm
10% = 18 bpm
15% = 26 bpm
20% = 35 bpm
25% = 44 bpm
30% = 53 bpm
35% = 62 bpm
40% = 70 bpm
45% = 79 bpm
50% = 88 bpm
55% = 97 bpm
60% = 106 bpm
65% = 114 bpm
70% = 123 bpm
75% = 132 bpm
80% = 141 bpm
85% = 150 bpm
90% = 158 bpm
95% = 167 bpm
100% = 176 bpm

The other one has a name, the Karvonen method. Am I allowed to use a motoring analogy on a cycling forum? The Karvonen method treats tickover as 0% rather than when the engine is off. The maths goes like this: ((heart rate)/(maxHR - RHR))+RHR. Using your RHR of 56 and maxHR of 176, we can calculate these %HRmax figures for you:
0% = 56 bpm
5% = 62 bpm
10% = 68 bpm
15% = 74 bpm
20% = 80 bpm
25% = 86 bpm
30% = 92 bpm
35% = 98 bpm
40% = 104 bpm
45% = 110 bpm
50% = 116 bpm
55% = 122 bpm
60% = 128 bpm
65% = 134 bpm
70% = 140 bpm
75% = 146 bpm
80% = 152 bpm
85% = 158 bpm
90% = 164 bpm
95% = 170 bpm
100% = 176 bpm

Your commute HR of 130 bpm would be stated as being 74% using the simple method and 62% using the Karvonen method. What's the difference and what does that mean? You mention the carb burning zone. Up to about 70%HRmax you burn some carbs and some fat. These are the base mileage rides where you can put in a lot of miles - LSD has been mentioned. The simple method says your commute at 74% is overdoing it if you want to stay below 70% so you slow down. Conversely, the Karvonen method says your commute at 62% means you can speed up and exert more energy while staying under 70%HRmax.

I learnt this from NickM in the days of the C+ forum and despite a lot of reading I cannot find which method the recommended zones are based on. Does your body start burning a higher proportion of carbs at 123bpm or 140 bpm (using your heart rates)? So, which method you choose to use becomes another Shimano/Campagnolo choice with proponents of both methods.

In 4 years of playing around with an HRM I have found the Karvonen more precise. I keep four figures in my head as a guide while I ride. If I had your HR figures, they would be:
60% = 128 bpm
70% = 140 bpm
80% = 152 bpm
90% = 164 bpm

Regarding zones, I have read a lot and forgotten a lot. I simplified it for me to:
50-60% = recovery (tired, ill, shattered)
60-70% = warm-up and LSD/base miles
70-80% = normal
80-90% = exerting (long uphills, honking)
90-100% = anaerobic (short bursts of uphill, overtaking, accelerating & sprinting only)

Re: Help with HR zones please - I'm shite at maths
« Reply #7 on: June 01, 2008, 07:04:00 pm »
Thank you.  Very informative.  I don't think I am pushing it at 130 bpm so I guess the Karvonen method is more to my suiting.
Nice one.

Re: Help with HR zones please - I'm shite at maths
« Reply #8 on: June 01, 2008, 09:43:24 pm »
What road-runner says about the Karvonen method is correct and the 70% threshhold using this method is often stated as the golden rule of heart rate training.

There is loads and loads of info on heart rate training at Runner's World UK most of which is easily translatable for cycling...

Re: Help with HR zones please - I'm shite at maths
« Reply #9 on: June 01, 2008, 11:08:56 pm »
I've printed off RoadRunner's little summary of the K method and cellotaped it to each stem.
Even if I say so myself, it looks quite neat  :thumbsup:

Re: Help with HR zones please - I'm shite at maths
« Reply #10 on: June 04, 2008, 09:15:12 pm »
Using these figures :

60% = 128 bpm
70% = 140 bpm
80% = 152 bpm
90% = 164 bpm

My commute today of 46 miles ( 2 x 23 ) was done at an average HR of 60% and an average speed of 18.15 mph  ;D  :thumbsup:  ;D  :thumbsup:

Re: Help with HR zones please - I'm shite at maths
« Reply #11 on: June 06, 2008, 02:49:57 pm »
Surely though, the body slips seamlessly from burning fat to burning glycogen. As the %HR increases the proportions of what is being burnt will be a smooth curve, not a series of incremental steps.
Rust never sleeps

Re: Help with HR zones please - I'm shite at maths
« Reply #12 on: June 06, 2008, 03:30:30 pm »
0% = 0 bpm

0 bpm = dead, surely?

 ;) for it is I, NickM...

...The Karvonen method treats tickover as 0% rather than when the engine is off. The maths goes like this: ((heart rate)/(maxHR - RHR))+RHR. Using your RHR of 56 and maxHR of 176, we can calculate these %HRmax figures for you...

Not %HRmax in the Karvonen method, but %HRreserve. The heart rate reserve being the blood pumping capacity you have to spare for effort after taking care of the essential blood flow needed for just staying alive and conscious. 120 beats/min, in your example, of the maximum 176 available.

%HRreserve is closely analagous to %VO2max (percentage maximum oxygen uptake) in the endurance exercise intensity domain (as the exercise physiologists say), which is why it is particularly useful - it gives a fair indication of %Vo2max without needing expensive and/or cumbersome expired gas analysis gear.

You use some carbohydrate (CHO) even at very low exercise intensities. And as has been said, fuel mix vs. exercise intensity is a continuum - there is no sudden switch to CHO at threshold, even if above threshold no additional fat can be utilised and all of the increase in energy metabolism must be fuelled by CHO. %energy from CHO vs. exercise intensity is a curve with a kink.
Profit or planet?

cometworm

Re: Help with HR zones please - I'm shite at maths
« Reply #13 on: June 06, 2008, 07:01:30 pm »

The numbers on the link above (Machine-head calculator) don't quite tally (for me, anyway) with the numbers I got from a full-on metabolic profile I did earlier this year, with Peter Byworth (think his outfit is called VO2forTri or similar). He uses a smaller number of zones, to make it easier to stay in zone (and I guess in recognition of the fact that it's kind of an inexact science):

Zone:   Description:   Range: (HR)   As % of Max HR Max
RECOVERY   RECOVERY   Sub 140   Sub 72%
ZONE 1   Optimum fat Burn/Base   140150   Approx. 72-78%
ZONE 2   Aerobic Fitness   150-175   Approx. 78-91%
ZONE 3   Anaerobic Fitness   175-Max HR [192]   Approx. 91-100%

If you're having trouble staying in each of the 5 zones, you could probably make do with fewer zones!