Tuesday, March 01, 2011

Determining maximum heart rate

On the heels of last weeks post on staying in the correct heart rate zone, this week I have decided to spend a little time looking at the concept of maximum heart rate (HRmax).

Maximum heart rate is defined as the highest number of times the heart can beat in 1 minute. It is an individual number, and one that cannot be trained to be higher.

There are 2 methods which can be used to determine HRmax:

1: Field test: Sample field test or Exercise test: Simple Lab test

Both of these tests are best performed by a qualified Exercise Physiologist or Sport Scientist as they require the athlete to perform a maximal test specific to their sport or event.

Tests are traditionally incremental in nature, meaning they progressively get more challenging as the test progresses. In the laboratory setting, other parameters are also tested in conjunction with heart rate, including: VO2max and Anaerobic Threshold.

For the majority of us who do not have a personal Exercise Physiologist, training coach or access to a lab, the old HRmax prediction equations make an appearance.
Predicting HRmax.

2: Age based prediction formulas
I am sure that the majority of you have heard of the old: 220 - age formula.

Well it interesting that there is very little scientific literature on this equation. In fact, no one is 100% sure from where the equation was actually derived. It has, over the decades, just become an accepted method of predicting HRmax.

Many have been extremely frustrated because it is in fact a very inaccurate and unreliable predictor of HRmax, and there are few (if any) citeable sources that validate the 220-age equation.

HRmax = 220 – age (males)
HRmax = 226 – age (females)

My predicted HRmax using 220 - age is 185b/min.

Over the decades a little more investigation was put into creating a more reliable and valid predictor of HRmax. Researchers from around the world have come up with numerous variations on the 220 - age equation, and the accuracy has become far superior to compared to what it was.

These more recent methodolgies far more accurate predicted HRmax values (not nearly 100% though).

HRmax = 208 – (0.7 X age) - 183.5b/min
HRmax = 205.8 – (0.685 X age) - 183b/min
HRmax = 206.3 – (0.711 X age) - 181b/min
HRmax = 206.9 − (0.67 × age) - 184b/min
HRmax = 191.5 − (0.007 × age2)- 183b/min
HRmax = 163 + (1.16 × age) − (0.018 × (age.age)) - 182b/min

Using the above equations to predict my maximum heart rate I get values of between 181 b/min and 184/min. So even through 220 - age has no "real' foundation it is still fairly close to the values calculated using the more up-to-date equations.

My tested maximum heart rate is 179 b/min so this is about 3 - 6b/min lower than the predicted values. Not enormous, but enough to make a difference when setting up heart rate training zones.

For most people using heart rate training for their training, I would recommend using the most recent (and accurate) equation of the lot:

HRmax = 191.5 − ((0.007 × (agexage))

This equation has been shown to be within 2 - 5b/min of tested values - pretty much as close you are going to get, with out performing a maximal test.

Happy training
Coach James

James is a veteran training coach at Innovative Fitness in Kitsilano. He hold a post graduate degree in Sports Science and is a Certified Strength and Conditioning Specialist with the NSCA. He also coaches Endurance athletes of all disci
plines from triathlon to cycling and running

No comments: