Fitness Test for Polar HRM - v02 Max

greekygirl

I re-took the fitness test on my polar HRM about a week ago because I hadn't taken it since I got it in January and I know I'm in better shape now. According to the manual, my results said I went from "very good" to "elite"! However, now the calorie burn is much higher than before I redid it - does v02 setting have that much of an effect on calories burned?

firedragon064

Yup, the higher VO2 max, you will burn higher calorie.

greekygirl

Ok thank you. I didn't realize it made THAT much of a difference. I guess I'll go with it!

cardbucfan

Oh, tell me about this fitness test!! What model Polar do you have? I'm getting a new one tomorrow F4 (I ordered it myself so I know I'm getting it!) because my old Polar is starting to poop out on me. What does the fitness test do and will my model have this????

greekygirl

Hi there! I have an RS300x. I don't know about the other models but it's a test you do when you set up your HRM before using it.

slieber

That's odd that the cal burn went up as you went up in fitness. Mine went down! I have the FT40.

Azdak

Yes, VO2 will have an effect. All HRM calorie estimates are based on the relationship between heart rate the oxygen uptake (VO2) during steady-state aerobic exercise. Under these conditions, there is a predictable relationship between "percent of max heart rate" and "percent of maximum oxygen uptake (VO2max)".

It's the VO2 number that is essential to know when estimating exercise calories. Since that can only be measured specifically via a metabolic cart, HRMs try to estimate your VO2 (and thus calorie burn) via heart rate.

For example, we know that 70% of one's HRmax is equal to about 57% of one's VO2max (during steady-state aerobic exercise). If we know that one's VO2max is 40 ml/kg/min, we can calculate that, if they are working at 70% of HRmax, they will be working at a VO2 of approximately 23 ml/kg/min (57% of 40) or 6.5 METs. If they weighed 80kg, then their calorie burn per hour would be about 520 calories.

VO2max increases with training, while HRmax does not. So, after training, for any given submaximal heart rate, you should be working at a higher VO2, and thus burning more calories (unless your weight has decreased). Using the numbers above, if one increased VO2max from 40 to 50 ml/kg/min and worked at the same 70% of HRmax, VO2 would now be 28.5, or approximately 8 METs. If weight was the same (80kg), you would now be burning 640 cals/hour at that same effort level.

(Because your fitness level has increased, the *absolute* workload will be significantly higher --running speed, avg watts on a bike, etc. But since the VO2max number has increased, the harder workload should "feel" the same as before);.

Now, there are a lot of "ifs" and "estimate" involved here, so that's why you cannot use HRM calorie readouts as precise measurements under any circumstances.

And the relationship between changes in resting HR and increased VO2max are tenuous at best, so, again, be cautious about your HRM calorie numbers.

Most people do not update their VO2max settings, or cannot update them. When their exercise heart rate decreases with training, they assume that calorie burn decreases as well. With so many people using (and misreading) their HRMs, the incorrect assumption that "calorie burn decreases as you become more fit" is consider an accepted "truth" even by many trainers, when in fact it is almost 100% wrong.

Azdak

That's odd that the cal burn went up as you went up in fitness. Mine went down! I have the FT40.

The calorie burn will go down if your weight decreases. Otherwise, you need to update your settings. I'm pretty sure the FT40 has some of the same features as the RS300x, including the fitness test and the ability to manually input VO2max.

Libby81

I have the FT40 and you can to this test on there. Make sure you update the weight settings as well as taking the fitness test to make sure the readings are as accurate as possible. I would still always trust my HRM over machines or stab in the dark predictions

slieber

I did do all the updates and my burn rate still went down. A half hour on the elliptical doing interval used to give me 200 and something (not much more) cals. Now it gets me to 176ish.

Ballet class - an hour and a half - used to get me around 450 cals. Now I'm lucky to get 350. I just attributed it being more fit.

Azdak

I did do all the updates and my burn rate still went down. A half hour on the elliptical doing interval used to give me 200 and something (not much more) cals. Now it gets me to 176ish.

Ballet class - an hour and a half - used to get me around 450 cals. Now I'm lucky to get 350. I just attributed it being more fit.

Not necessarily. It depends partly on what you are comparing. The first couple of weeks of working out really don't count, especially if you are doing an activity that requires more complex movements. The body's response can be somewhat inconsistent at first. That's why, when they do studies involving newer pieces of equipment, there is always a "habituation" period before they do the actual "pre test" for the study.

If weight has unchanged, but calorie expenditure is going down, then you either have not readjusted your settings enough or you aren't putting forth the same effort as before. The popular idea that "improved fitness decreases calorie burn" is just not true in most cases--certainly not for the elliptical. If you are burning more total calories per the machine readout for your entire workout, then you are burning more calories--even if the actual machine number is not accurate. So, if the machine number is going up, but your HRM number is going down, then it's your HRM that is not set up properly.

Ballet class might be one of the few exceptions. Because the structure of the class and movements are limited by the choreography, it is possible that increased movement efficiency could account for a decrease in calories. Plus, you are limited as to how hard you can push yourself. With something like running, you can always run faster as fitness improves, but, in ballet, you might not be able to jump higher or turn faster, so it is more likely that the actual calorie burn will lower a little over time. Because of the nature of the movements, HRMs are a little more "iffy" during a ballet class.

slieber

So if I'm reading this right, my HRM may need recalibration of some sort. The machine cals have been consistent since the start, but they only take in weight, so I haven't been using them. My HRM registered 100 cals fewer consistently, till the past few months, when they went under for the same amount of time and similar style exercise.

Would metabolic troubles figure into this? I found recently I have an underactive thyroid and now have to take thyroid replacement. I'm still in the stabilization stage - we haven't found quite the right amount.

Ballet does get more efficient in the use of muscles, so I'm not overly concerned about that as much. With a new teacher and pacy class, I get the usual burn, then it goes down within weeks if I stick to the same teacher.

slieber

Re-did my fitness test and have now a higher v02 max than the last time (thanks to conscientiously working out for the past several weeks!!). It did translate into more calorie burn, albeit not a huge amount more. Will just have to see how it goes...