How to test HRM for how accurate calorie burn is

Well, perhaps you know that HRM estimated calorie burn can be off, especially if you don't have correct stats in it.

It's always claimed it's much more accurate than MFP or other databases, or machine, ect. That claim is usually based on nothing more than observation that it is different than those other sources. If you have made such a claim, think about why you believe that is the case.
It's also always assumed the reading is high if it isn't trusted already, as you can find out below, that is bad assumption too.

Since HRM has definite reason it would have trouble giving decent estimate of calorie burns, or times it should not be used for that purpose anyway, it should be used at correct times if calorie burn is the purpose.
http://www.myfitnesspal.com/topics/show/773451-is-my-hrm-giving-me-incorrect-calorie-burn

How to test how accurate yours is for you?

Well, studies have shown that walking between 2-4 mph level, and basing calculations on formula's, is much more accurate than the 15-25% accuracy a HRM may get if properly set up. And that's 15-25% either direction, not just inflated.

http://www.ncbi.nlm.nih.gov/pubmed/15570150

(4.2 kJ is 1 calorie. Notice the energy expenditure on treadmill and track is almost equal.)

That test Walking was 3.2 mph level for 1 mile for 19 min, calculation was 3.4 calories higher than tested 81 cal, or 4.2% higher.
Running at 6.3 mph level for 1 mile for 9.5 min, calculation was 4.8 calories lower than tested 115 cal, or 4.2% lower.

Why? It literally takes so much energy to move so much mass at so fast a pace for so much time.
Does the amount of energy to lift a 5 lb weight vary if you are male or female, old or young, or is the weight still 5 lbs? :drinker:
It may be easier or harder, but the energy expended is the same. Perhaps a difficult concept to wrap mind around. Now, 5 lb at the end of a short or long arm lifting in front of you, sure, different.

Even adding a bit of incline is more accurate than HRM. Because unless you have far from avg efficiency walking (club foot, fake leg, ect), the calculations are more accurate.

So you can do this before your next regular workout just to know how correct your HRM is.

1 - Confirm your HRM has correct stats. The weight should be your total weight with clothes and shoes you are wearing while exercising. Unless you really are walking naked. Recommend not doing that in the gym.

2 - If treadmill allows weight entry, get it correct too.

3 - 10 min warmup walk, higher HR is better, so probably 4 mph. If HR is not up to at least 120 bpm, then increase incline until it is at 120 and holds steady until the end of the 10 min. Lower speed if you are hitting 120 at 4 mph.

4 - Now start your 20 min test walk, by starting your HRM for actually logging the workout for this next 20 min. Leave the incline where it's at, even if HR starts going up slightly.

5 - At end of 20 min, stop the HRM, note the pace and incline you used, and the weight you were for the test.

6 - Now take your stats to this site, and using the pace and grade, weight on treadmill and your 20 min, use the Gross option (that's what the HRM and treadmill will report, Gross. For purpose of eatback, it would be Net).

http://www.exrx.net/Calculators/WalkRunMETs.html

Now you have the best estimate of calorie burn.

What did your HRM say?

Difference / calculated = % error

The % off will go up as HR goes up.

You can certainly test at another HR to see, but keep it at walking, and lower incline the better accuracy. As soon as you are running, then personal efficiency and method can vary greatly from avg, though it could be much better still if you look at that test data.

So what does the difference in HR mean then? What about 3 months ago when my HR would have been 15 bpm higher perhaps doing this same workout?

A high HR means you needed more oxygen to burn the required fuel, so more carbs being burned, low HR means more fat now.
In addition to this, if you are moving more oxygen with each heart beat compared to 3 months ago because you are more aerobically fit, the HR doesn't have to go as high to provide required oxygen.
That's where the VO2max stat comes into play to help accuracy.

Well, have fun testing.

And if you do have Polar with VO2max self test, at least get the resting HR in the morning and answer the Athlete question correctly.
The correct settings for Athlete and accuracy of their test.
http://www.polar.fi/about_polar/who_we_are/research/fitness_test_with_OwnIndex


Since so many are counting on HRM for "accurate" calorie burns for eating back, or assuming it's always inflated, or have no idea - thought this would be useful self test to show yourself.