Posted: December 14, 2004

Multisport: Finding Your Maximum Aerobic Heart Rate

From: EnduranceCoach.com
By Coach Mark.

Recently I read an article titled: `Building Blocks' by Mark Allen ('Triathlete' magazine, March 2004) that dealt with the importance of building a good base by training below your maximum aerobic heart rate. The article covered how to find this heart rate and the reasons why training at this intensity is crucial.

With some athletes I'm coaching just starting into their base training, I decided to use some of what Allen had to say to explain the importance to them of training easier rather than harder to get the best long term results.

Of special interest to me was the formula Allen uses to calculate an athletes maximum aerobic training heart rate because it doesn't require you to know your maximum heart rate. The formula, or calculation is:

1. Take 180 and subtract your age.
 
2. Take that number and correct it by the amount next to the statement that best describes your level of fitness:
 
a. Subtract five beats if you are recovering from a major illness or injury that has kept you from training for six months or more.

b. Leave the number where it is if you have been working out about two to three days per week for at least a year.

c. Add five beats if you have been working out more than three days per week for at least a year.

d. Add 10 beats if you have been working out more than five days per week for at least five years without recurring colds, illnesses, injuries or long periods of burnout.

e. If you are older than 55 years old or younger than 25 years old, add an additional five beats to whatever number you have right now.

(Note: if you are trying to decide between two of the above statements, it is much better to pick the one that gives you a lower training heart rate than the one that will give you the higher training heart rate.)

How Does This Compare with Other Methods?

Using this method to obtain my own heart rates, I used: 180 - 34 = 146, then add (d) from above, so, 156bpm. After working through this I decided to sit down and cross reference it with a few other methods used to determine training zones to see exactly where it fitted into the grand scheme of things. The methods I used to cross reference were:

· Percentages of predicted maximum heart rate
· Percentages of actual maximum heart rate
· Percentages of heart rate range using the Karvonen formula
· the method of determining heart rate training zones utilized at EnduranceCoach courtesy of Coach Brendon (which can be found in the article How to Set Accurate Training Zones)

To cross-reference the different methods I chose three key maximum heart rate percentages. NOTE: these are representative percentages only. Lab testing would in most cases give more accurate percentages.

· 60%: the percentage at which significant aerobic training takes place and below which I would describe as recovery training. We can call this aerobic threshold
· 80%: the percentage that is the maximum aerobic training heart rate
· 85%: the Anaerobic Threshold (AT)

Results of Cross Referencing with Other Methods

As with the Allen method above, as an example for each calculation I have used my own heart rate data.

Method 1: Predicted Maximum Heart Rate

Using: 220 - age to predict maximum heart rate. At the ripe old age of 34, my predicted max would be 186.
 
x 60% = 112 bpm
 
x 80% = 149 bpm
 
x 85% = 158 bpm

Method 2: Actual Maximum Heart Rate

Using: My actual maximum heart rate which is 197

x 60% = 118 bpm
 
x 80% = 158 bpm
 
x 85% = 167 bpm
 

Method 3: Karvonen Formula

Maximum Heart Rate - Resting Heart Rate = Heart Rate Range (HRR) Eg: my HRR is 197 - 40 = 157

HRR x 60% = 94 bpm
 
HRR x 80% = 126 bpm

HRR x 85% = 133 bpm
 
Finally add Resting Heart Rate to these figures:
 
60% = 94 + 40 = 134bpm

80% = 126 + 40 = 166bpm

85% = 133 + 40 = 173bpm
 

Method 4: EnduranceCoach.com Training Zones

Four key heart rates are needed to begin with: (Mine are in brackets)

1) Maximum Heart rate (197)
 
2) Resting Heart rate (40)
 
3) Aerobic Threshold. Half way between maximum and minimum heart rates (half way between 197 and 40 = 119)

4) Anaerobic Threshold (AT). ( I will use 173 from the Karvonen formula above. Once again, this should really be accurately assessed for best results.)
 
Rather than splitting HR's into percentages, Training Heart Rates are split into 6 zones in the following way:

Very Easy = below aerobic threshold (eg: below 119 bpm)
 
Easy = lower 1/3 of zone between aerobic threshold and anaerobic threshold (119bpm-137bpm)
 
Moderate = middle 1/3 of zone between aerobic threshold and anaerobic threshold (137bpm-155bpm)

Hard = Upper 1/3 of zone between aerobic threshold and anaerobic threshold (155bpm-173bpm)

Very Hard = From your anaerobic threshold, halfway up to your maximum (173bpm-185 bpm)

Very Very Hard = From halfway between your anaerobic threshold and your maximum, up to your maximum (185bpm-197bpm)

Observations after Cross Referencing

· For me, the first thing to note is that using the Predicted maximum heart rate calculation of 220 - age is a waste of time. My actual Maximum is 13 bpm higher than predicted. There are other Predicted Heart Rate formulas that may be more accurate.
· The figures obtained using the Karvonen formula are consistently higher than the other calculations. The figure I would use personally from this method is the one for 85% or AT. Having field-tested different heart rates over a number of years of training, 173bpm feels about right for my AT. Early in my build up it may be a few beats below this, when fit, a few beats higher. As you will see below, when using this figure, the EnduranceCoach method fits into the puzzle quite nicely.
· There are heart rates that occur in more than one method of calculation. The first is the 60% aerobic threshold heart rate: 118 in Actual maximum heart rate calculations and 119 using the EnduranceCoach calculation. The second, and the one which is the purpose of this article, is the 80% (maximum aerobic training) heart rate: 156 for the Mark Allen method, 155 for the Actual Maximum heart rate method, and looking at the EnduranceCoach method, 155bpm where Moderate intensity ends and Hard intensity begins.

Conclusions About Determining Training Heart Rates