VO2max setting on HRMs

SparkPoints: (34,005)
Fitness Minutes: (67,171)
Posts: 3,628
9/20/11 4:04 A

Formulas for Calories form factors

Using VO2max:

Men: C/min = (-59.3954 + (-36.3781 + 0.271 x age + 0.394 x weight + 0.404 x VO2max + 0.634 x HR))/4.184
Women: C/min = (-59.3954 + (0.274 x age + 0.103 x weight + 0.380 x VO2max + 0.450 x HR)) / 4.184

Without VO2max:

Men: C/min = (-55.0969 + 0.6309 x HR + 0.1988 x weight + 0.2017 x age) / 4.184
Women: C/min = (-20.4022 + 0.4472 x HR - 0.1263 x weight + 0.074 x age) / 4.184

I have theise in excel to simplify doing the math.

SparkPoints: (5)
Fitness Minutes: (0)
Posts: 1
9/19/11 6:29 P

Anyone out there use a program online (or downloaded) that factors in Vo2 and RMR?

Posts: 822
6/5/11 5:25 P

I think the machine assumes that if your VO2max is higher you are more fit, more likely to have a lower resting heartrate and more likely to have a slower heartrate response to increasing workloads. So someone who is out of shape may jump right up to 140 beats/minute at a low workload where someone fit would have to be sprinting to get that high. So for any given heartrate the more fit person is burning more calories.

SparkPoints: (93,883)
Fitness Minutes: (50,655)
Posts: 3,464
6/5/11 8:21 A

IT is helpful, thank you. Now I'm kind of ticked that I bothered buying a HRM in the first place since it is telling me nothing LOL

SparkPoints: (34,005)
Fitness Minutes: (67,171)
Posts: 3,628
6/5/11 8:11 A

I had V02Max testing done as part of a research project at a local university. This was last April. At the time I found 3 research projects in the 5 min I spent looking, that required the subject to undergo V02Max testing. so if you live near a university or college you may be able to get a lab test for free.

As far as the estimate and heart rate monitor go. I use one for running. I reduce the calorie estimate by 10-15% from what is reported on a normall run. I have a friend who uses the same math for running and who bumps up the estimate by 10% so we have 20% adjustment that we make to make the reported calories work well with our real world results. Running and heart rate monitors are the best you are likely to do outside a lab, and so you can see that If she and I both got an estimate of 1000 calories burned for a given run, I woul look at it as 850 calories and she would look at it as 1100 caloreis. That is 250 calories differences. Why do we each make an adjustment. The reason is that over time I have found it works better for me with what happens in the real world. Weight losse, inches, etc if I reduce it, and she has found that it works better for her if she adjusts up a little.

This is not an exact science.

Hope this is helpful

Popie

SparkPoints: (93,883)
Fitness Minutes: (50,655)
Posts: 3,464
6/4/11 7:32 P

Haha, yes it is confusing, but thank you! I know I need to stop worrying about the numbers.

SparkPoints: (28,476)
Fitness Minutes: (59,158)
Posts: 1,219
6/4/11 7:23 P

To clarify on the point I made... If you have two people with the same age, size, gender using a heart rate monitor. One person is fitter so has a higher VO2Max and possibly more muscle mass in their weight, the other less fit one more fat and lower VO2Max. They both exercise for 30 minutes and achieve the exact same heart rates--the fitter one should burn more calories and according to our HRM's they would. Now, that does not necessarily apply to you doing the exact same workout on different days because-- as you increase your fitness your heart rate will likely decrease during the same activity as you are in better condition. So you doing that after a fitness improvement would be:
1--A person with lower VO2Max and possibly higher body weight doing a challenging 30 minutes workout and achieving the heart rate.
Compared with 2--A fitter person with possibly lower body weight doing the same workout and achieving a lower heart rate (as the exact workout it now is easier for you.)

In the situation involving you, your calorie burn is most likely lower since your workout was not as intense for you and especially if you are smaller. In the situation where all is equal except the VO2Max (equal age, weight, gender, intensity of workout=heart rate) the person with higher VO2Max would burn more. But presumably a fit person works harder to get their heart rate up i.e. running faster,etc. than when they were less fit where they could do it with a slower jog or even a walk. I am not sure if in real life it is that easy as there are a lot of factors involved in calorie burn that are quite individual.

However, the often repeated advice is to use your nutrition to lose weight (as it is the biggest factor) and to use your exercise to get fit. Sure good nutrition supports increased fitness and exercise burns calories and helps with fat loss. The estimates you are getting should be enough to help you compare intensity of your workouts, use as a tool to increase or decrease intensity, get an estimate on calories burned for the Spark nutrition tracker (so it can help you with a good calorie range), monitor improvements in your own fitness, etc. I know it is kind of confusing.

Edited by: SLYSAM at: 6/4/2011 (19:29)

SparkPoints: (93,883)
Fitness Minutes: (50,655)
Posts: 3,464
6/4/11 4:44 P

Are high school tracks a standard distance? We only have one track and I have no idea how big it is. Would it say somewhere at the track? There's no one to ask on a Sunday morning.

SparkPoints: (93,883)
Fitness Minutes: (50,655)
Posts: 3,464
6/4/11 4:39 P

I was looking at that - I might do it tomorrow.

My problem is not determining my VO2max. I actually trust the number I got using my 5K time. I am just confused as to why my calorie burns appear lower using the less fit VO2 number. As I stated in my original post, I thought fitter people burn fewer calories for the same workout as compared to someone not as fit (assuming weight and gender etc are equal) because they are more efficient.

SparkPoints: (28,096)
Fitness Minutes: (12,495)
Posts: 2,310
6/4/11 4:30 P

Jolinar, FWIW try the Cooper's test. At least you'll get another possible VO2max number and there's also a nifty table to compare your results:

http://en.wikipedia.org/wiki/Cooper_test
http://www.brianmac.co.uk/gentest.htm

Takes only 12 minutes on the track, add a few for warming up first.

SparkPoints: (93,883)
Fitness Minutes: (50,655)
Posts: 3,464
6/4/11 3:51 P

I would use an online calculator but honestly, I can't really judge how hard I'm working. And doing intervals, it's hard to focus on how much "rest/recovery" time I'm actually getting. When I do Insanity, there's a warm up, a fairly lengthy stretch, then the intervals and sometimes the breaks are longer than others.

I've always felt that exercise isn't a big factor in losing weight and that diet is much more important but damn, if I'm only burning 300 calories per hour for busting my butt, it's not worth it at all from a caloric deficit standpoint. Yes, there are other benefits to exercise and that's why I don't skip workouts even when my diet is crap.

I would love to not care about the numbers and just eat/exercise by listening to my body but I can't. I'll never be intuitive.

SparkPoints: (28,096)
Fitness Minutes: (12,495)
Posts: 2,310
6/4/11 3:36 P

I don't know which formula Polar uses, but one commonly found is this:

Using VO2max
Men: C/min = (-59.3954 + (-36.3781 + 0.271 x age + 0.394 x weight + 0.404 x VO2max + 0.634 x HR))/4.184
Women: C/min = (-59.3954 + (0.274 x age + 0.103 x weight + 0.380 x VO2max + 0.450 x HR)) / 4.184

--

Using the above formula, you'll note that e.g. men will burn about 6 calories more per hour per one added unit of VO2max. I tested my VO2max using the Cooper's test, and since my Polar is old as old as the hills, I take my calories burned numbers from an online calculator.

I guess the mystery was how a fit person burns more than unfit one? My bet is that a fit person running at same average HR will run so much farther in the same time as to account for that additional burn of calories.

SparkPoints: (93,883)
Fitness Minutes: (50,655)
Posts: 3,464
6/4/11 2:54 P

My HRM is an older model so it doesn't automatically update the VO2. And yes, I know I'm not burning fewer calories LOL It's just showing that I am. I know it's all an estimate, I know, I know, I know. But Polar is supposed to be one of the more reliable ones and I have no idea how many I'm burning, and apparently, I can't even get a decent estimate if the discrepancy is that big.

So "the higher the Vo2Max the more calories burned" - that's also what you see from your Polar? Does that mean fitter people burn more calories? I thought the opposite was true. I guess that is what I'm confused about. If having a lower (approximate) VO2 means I'm burning fewer calories than I thought, then fine. But that would explain why I've been having trouble losing, if my calorie burn has been overestimated so badly for the last 18 months.

SparkPoints: (28,476)
Fitness Minutes: (59,158)
Posts: 1,219
6/4/11 2:36 P

I am curious about this as well. But I will say that it does make a difference in how my Polar F11 calculates calories burned--the higher the Vo2Max the more calories burned. I've hear that is true. I don't actually know mine, my hrm has a test it does that seems like a resting pulse test that has something to do with heart rate variability. I've not had an actual lab test done, but if you know yours your hrm should be more accurate. Since calories burned have to do with oxygen consumption it makes sense that VO2 would be important (the calories burned is not specifically heart rate that is just used to estimate oxygen consumption outside a lab) (is consumption the right word?). Does heart rate decrease because VO2 increased? My semi-educated lay person guess is that it would because your heart doesn't need to work as hard to supply oxygen to your muscles when you have a higher VO2Max. I've also heard muscle mass or lack of is a big factor in calorie burn but it is not a factor used in most hrms so it could also be they are using a major fitness benchmark to infer others. Hopefully some of the experts on site will clarify. :-)

Does your monitor automatically enter a number in that category? Mine does from the fitness test and the number seems similar to what I got doing one of the tests on the page you suggested. But of course it is just an estimate not a direct measurement. Just like calories burned from a hrm is just an estimate not a direct measure. If you were able to comfortably do insanity you probably have decent aerobic fitness. Sometimes fixating on calories burned through exercise can be counter-productive. Remember all measures are estimates. So it is incorrect to say you "burned 125 calories less than on month ago". You burned what you burned and your body knows the truth--the estimates your hrm gave you are not necessarily correct (either the higher, the lower or both may be wrong).

I would think the more information considered, the more accurate. If you are really concerned about improving accuracy perhaps you could get your VO2 Max tested at a local university.

SparkPoints: (93,883)
Fitness Minutes: (50,655)
Posts: 3,464
6/3/11 9:26 P

Can someone explain this to me? I know what VO2max is. I know the only way to get an accurate testing is in a lab. But I don't understand how it affects calories burned. I was under the impression that the more fit you are, the higher your VO2max, the fewer calories you burn compared to someone with a lower VO2max.

I have previously done some at-home VO2 testing and used the number I got for the Rockport walking test www.brianmac.co.uk/rockport.htm . I used that number for over a year, but when I recently did Insanity, my calorie burns were fairly low. So I did some more research and found another way to approximate VO2max - using a 5K race time www.brianmac.co.uk/vo2race.htm . That number is a lot lower than the one from the walking test, and I suspect it is more accurate (there's no way my big butt, barely runs 3 miles self has a VO2max of 44!). So, I changed my HRM setting to reflect the (what I feel is) more accurate number of 34 (closer to 35 though).

I did my first workout today since changing that setting (all other settings remained the same) and I burned 125 fewer calories today than I did doing the same workout just one month ago. That's a pretty big difference. What good is a heart rate monitor (Polar F6) if I can't even get close to what I'm burning? I know HRMs are just an estimate but 100+ calories for a 30 minute workout is a huge difference.

I am sure I had good contact with my chest strap (which I replaced a few months ago, so I know it's not the battery in the strap). I kept an eye on my HRM the whole time to make sure it was getting a reading. I know it's really not that big of a deal but I depend on having a fairly close approximation of what I'm burning so I can monitor my caloric deficit. I'm to the point where it's very difficult to lose so that is important to me. I don't know what's more accurate - the lower number or the higher number or should I split the difference? I do know that when I do cardio, even Insanity or running, I don't breathe heavy. I can fairly easily talk, and my breathing is steady, unless it's a super high intensity interval. My legs tend to fatigue before anything else.

Should I get a new heart rate monitor? Not worry about it at all? Should I do the fitness test for the HRM? It's over 2 years old and I've never done it but it's set up to determine my max heart rate based on whatever I'm doing. My resting heart rate is also accurate in the settings - I've calculated that multiple times upon waking. Actually, I'm not sure the F6 comes with a fitness test, other than the OwnZone thing (which usually calculats in the first 3-5 minutes of each workout to give me a target HR range) - I know the new HRMs do though.

It's frustrating and now I just need to know how VO2max and calories are related, for my own sanity

Edited by: JOLINAR at: 6/3/2011 (22:08)