How Accurate Is Your Garmin's VO2max Figure?

Updated: Apr 18, 2020

Where do you get the numbers?

Often a client will tell me their training zones. Which is great news, as it will usually mean I can far better accurately assess the intensities for the fitness assessments I do with them.

The conversation usually goes something along the lines of this:

  • Garry: “So what heart rate you do hold for a steady run/ride for about an hour”

  • Client: “Oh, I’ll be in zone 2 for that”

  • Garry: “Brilliant, do you know what heart rate value that actually is”

  • Client: “Er, no, not really. But I know that is where I should be doing my steady training”

  • Garry: “No problems, how did you set your zones”

  • Client: “Oh, not a clue. I just use the zones Garmin set for me”

  • Garry: “OK, not a problem. How did you assess your maximum heart rate?”

  • Client: “……er…..” at this point a bewildered look often follows. “I use the value Garmin sets for me????”

Now to be honest, I would probably get a more sensible answer if I was to quiz my daughter Pixie, and she’s three and still gets tomorrow and yesterday the wrong way around!

It’s really not an issue to me, after all, that is one of the main reasons people come in for testing: to get a true assessment of training zones.

Today was another classic example of how far the predictors used by most heart rate monitors/GPS systems can be out when guesstimating your training zones.

My client today is 70 this year, and so his Garmin was working on an estimate of 220-AGE (70) = 150, and then working as a percentage of this for a variety of training intensities.

So when he hit a maximum value of 172 beats/min, he realised how far out the training zones actually were, and it has given him a whole level of confidence In the ability to exercise a little harder.

However, in setting up our training zones we look for a critical threshold point, so we can even more accurately set up your personalised training zones, rather than rely on predictors.

So if you are going to spend £££ on a heart rate monitor of GPS system to train with, please get the best value from it by at least understand your heart rate zones, and train smarter not harder!

Get in touch today!


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