VO2 Max and how it impacts your Heart Rate Monitor Accuracy

After receiving my Polar Heart Rate Monitor in December I've used it for every single workout (and some non-workouts like moving and cleaning!) I love, love, love it but after a few weeks I noticed something that I thought seemed a bit off. On days I did heavy strength training the calories burned reported on the HR monitor was shockingly low. Like, I'd workout for an hour and burn 200 calories. I burn about 70 just laying on the couch for an hour so I felt like something wasn't right! After doing some research I concluded that the average pre-set VO2 Max of the Polar was lower than mine was and for a more accurate reporting I'd need to adjust that to reflect my specific numbers.


So, what the heck is VO2 Max? In the most basic way I can find to explain it - VO2 max is a number that indicates how efficiently your body uses oxygen. The higher the number the better your body is at using oxygen during exercise. The most accurate way to test your VO2 is via a sports lab and some fancy equipment. I checked locally at UWF does it for just under $200. A free, less accurate, way is to use any number of V02 Tests you can find online. Here are my two favorites:


Not feeling like doing some Math today? You can use these online calculators here (Hey, I think it's important to see how they are calculated!) For the first test my VO2 Max was 48, and for the second test it was 53. I split the difference and figured my VO2 Max is somewhere around 50. Looking at the table below, that's pretty good!VO2 Table

 {Table Source}

Although, it's not unusual for elite athletes to have VO2's into the 80's and 90's!

So - now what? Well, if you have a heart rate monitor you need to bust out the manual and see how to adjust the VO2 max. For the PolarFT40 it was ridiculously easy. I forget what it was preset to but I believe it was about 5-8 points lower than what my VO2 is. Not surprising since the HR monitors are likely pre-programmed to reflect the average VO2's given your height, weight , age and activity levels (all variables you usually have to put in before you can use the device.)

Since I made the adjustment I've noticed that my caloric expenditure is about 10-15% greater than it was before. I feel like it's a more accurate representation of how many calories I'm burning and it's important for me to know that so I can be sure to eat enough every day! I also like keeping track of how many calories I burn with each workout I do so I can see which one's are most efficient.

I think I've sufficiently overloaded you with information for today. If you have any questions at all about VO2 Max or how to calculate it, please leave me a comment! If you'd like to check out my overall review of the Polar you can see the original post here.

Has anyone had their VO2 max tested before? How many of you are going to try to make these adjustments on your HR monitors?