calories burnt HRM vs GYM EQUIPMENT...

My Polar FT4 syncs with the machine at the gym. Think the reading is accurate?

My Polar FT4 syncs with the machine at the gym. Think the reading is accurate?

My Polar also tries to synch with the treadmill, so I don't know why the readings are so off.

If C25K isn't good for HRM estimating, how am I supposed to know what I burn? This is frustrating.

It is important to remember they are all estimates based on different data. Your treadmill may ask for your heart rate but it may not be using it in the calorie burn formula and even if it is it would be using a different formula than your HRM. If you were to use two different models of HRM you might also have a different calorie burn with the same heart rate data. HRMS are usually using average heart rate for the workout and whatever profile stats it has on you. Usually it is some variation of what percent of your entered or estimated maximum heart rate the workout average reaches. It is estimating your oxygen use from your heart rate (in a lab they often use oxygen use to measure exertion and calorie burn). The treadmill is using different data. How to know which to believe? It is possible neither are accurate, but one or both may be close. I think the best thing is just to use the same estimate consistently and see how that works with your results. Hopefully both methods will credit you with more when you work harder and less if you just phone it in that day. I've not had any issues eating according to my HRM calorie burn, if it is wrong it isn't off by too much. With an HRM, don't be surprised if your calorie burn decreases even if your weight is the same. This can especially happen with programs like c25k since presumably your aerobic fitness will improve as you progress and your average heart rate may decrease (if you were to repeat your week one workout after you finish) in part because your heart rate will recover faster during the walk intervals and not stay so high. This results in a lower average heart rate for the workout. Of course, your program will progress in difficulty so that may only be apparent if you were to repeat workouts from a previous level. Some HRM's account for this by involving a fitness test to estimate lung capacity, but some just assume it based on your stats and you will see a decreased burn with increased fitness. I would use the HRM, personally, because it can also give you signs that your fitness is improving.

My Polar FT4 syncs with the machine at the gym. Think the reading is accurate?

My Polar also tries to synch with the treadmill, so I don't know why the readings are so off.

If C25K isn't good for HRM estimating, how am I supposed to know what I burn? This is frustrating.

It is important to remember they are all estimates based on different data. Your treadmill may ask for your heart rate but it may not be using it in the calorie burn formula and even if it is it would be using a different formula than your HRM. If you were to use two different models of HRM you might also have a different calorie burn with the same heart rate data. HRMS are usually using average heart rate for the workout and whatever profile stats it has on you. Usually it is some variation of what percent of your entered or estimated maximum heart rate the workout average reaches. It is estimating your oxygen use from your heart rate (in a lab they often use oxygen use to measure exertion and calorie burn). The treadmill is using different data. How to know which to believe? It is possible neither are accurate, but one or both may be close. I think the best thing is just to use the same estimate consistently and see how that works with your results. Hopefully both methods will credit you with more when you work harder and less if you just phone it in that day. I've not had any issues eating according to my HRM calorie burn, if it is wrong it isn't off by too much. With an HRM, don't be surprised if your calorie burn decreases even if your weight is the same. This can especially happen with programs like c25k since presumably your aerobic fitness will improve as you progress and your average heart rate may decrease (if you were to repeat your week one workout after you finish) in part because your heart rate will recover faster during the walk intervals and not stay so high. This results in a lower average heart rate for the workout. Of course, your program will progress in difficulty so that may only be apparent if you were to repeat workouts from a previous level. Some HRM's account for this by involving a fitness test to estimate lung capacity, but some just assume it based on your stats and you will see a decreased burn with increased fitness. I would use the HRM, personally, because it can also give you signs that your fitness is improving.

To answer the first part: commercial fitness equipment has polar-compatible receivers plugged into the machine consoles. That allows the heart rate signal from the chest strap to be displayed on the console. That's it. The machine calorie-estimating process is completely separate-there is no way a machine can "sync" a Polar receiver.

And, as I explain in the blog, the machines don't need heart rate to estimate expenditure. The machine can measure the actual workload being performed by the exerciser. That workload, along with user weight, are the ONLY factors necessary to estimate calories.

People have the mistaken idea that the extra inputs required by HRMs--age, gender, height, whatever--are a sign of greater accuracy. The fact is that HRMs need all of those extra variables, because the underlying algorithms are so inaccurate.

The reason why some machines (not all) are so inaccurate is because it is expensive to do validation studies for each individual machine and so they take shortcuts--they use walking/running equations for cross trainers, for example. Or they did a modest study 20 years ago on a limited sample (gave some $$ to a grad student) and have never updated it, even when they changed designs.

The main reason why HRMs are inaccurate is because of the innate variability of heart rate response--both between individuals and under different conditions in the same individual. On top of that, you have the imprecise setup that exists for probably 80% of HRM users.

Your last statement reveals one of the fundamental problems with HRMs. As fitness level increases, HR will decrease for any given submaximal workload. Thousands of people have come to believe that this means that you burn fewer calories as your fitness level increases. This is an example of an "Alice in Wonderland" situation where reality is cast aside and a false alternate reality has been constructed in its place. The fact is that energy expenditure for a given steady-state aerobic workload is relatively constant. If weight does not change, then neither will calorie burn, even through heart rate has decreased. Unless one can "reset the scale" by manually inputting increased VO2 max or using some other method to let the HRM know fitness level has increased, the HRM will continue to progressively underestimate calories.

That idea that an HRM can show improvements in fitness over time is also limited. It is true that one can look can average heart rate over time for the same workout and use that to gauge progress. However, avg heart rate is a relative measure, using avg heart rate for an entire workout can be misleading. If I do one workout now and have a HR avg of 140, and 4 wks later after my fitness level has improved, do a workout for the same amount of time and relative intensity and perform 15% more aerobic work during that workout, the HRM will still show and avg heart rate of 140, i.e. no improvement. A machine, OTOH, since it measures actual workload and actual work performed, will clearly show the increase in number of calories (aerobic work) "burned" during the workout. Even though that calorie number might be an overestimate, the difference between the two numbers will more accurately reflect the increase in fitness ability than avg HR from the HRM.

Thermal conditions, stress, illness, anxiety, medication, cardiovascular drift--all of these can affect both heart rate and HRM calorie readout. None of them affect the consistency of the machine readout.

So, basically I wasted sixty bucks on a HRM with no VO2max setting. Cool.

So, basically I wasted sixty bucks on a HRM with no VO2max setting. Cool.

This is kind of why my pet peeve here is when people tell others you "have" to get a HRM and talk about how it is so accurate and such.

I don't think you wasted the money though. It isn't perfect but a lot of people find success using them. Just be wary I excessively ugh burns. Plus a lot of people find them motivational and find they encourage them to push harder
Also if you get into running there are training applications for it.

I've been running for a couple of months now, but I'm just getting to the part in my 5K program where I run for longer amounts of time. My calorie burns usually read ~ 280 but I usually input 250 in case it's over. My heart rate, once I warm up, stays between 150 and 180 (tops out at 184 ish but has reached 190 once or twice) for about twenty minutes or so.