Is my HRM reading too high?

jojosteez

Hello everyone. I finally got around to getting a heart rate monitor (Polar FT4) to track my cardio sessions. Before that I was letting the machines read my HR and tell me calories burned. I normally do 20-30 minutes on the elliptical and 20 minutes or so walking on the treadmill at 3-3.5 mph. I do strength training in between cardio every other day also. My heart rate is usually 135-140 when on the elliptical and I average 10 Calories/min. On the treadmill it's about half the Calorie burn and Im usually around 120-125 bpm.

The FT4 is reading almost exactly the same as the elliptical but a little higher(12 Calories/min give or take). The treadmill is a different story. The FT4 shows TWICE the Calorie burn as the treadmill. My heart rate is reading the same on both for the whole time. Should I trust the HRM or go back to what the machine says? I have been losing weight at a steady pace, so what I have been doing is working. I'm just afraid to use the elevated numbers being reported by the HRM. Could it be faulty? Thanks in advance for any helpful info.

ksy1969

Did you go through the set up on the HRM? Your experience is the exact opposite of mine and many others I have talked too.

WalkingAlong

I would trust your HRM. What does your instinct tell you? Is the treadmill really about half the exertion as the elliptical (as the treadmill suggests) or is it about similar (as the HRM suggests)? I would think for most people, barring odd settings, they'd be more similar. If your HRM shows your HR about the same on both, that implies your calorie burn is about the same.

Does the treadmill get your HR from silver contacts you grab? Those can be pretty off, I think.

GetSoda

12 calories per minute is like, near maximum, constant exertion by a top level athlete.

I wouldn't trust anything much more than 3/minute for walking. Even for a large person.

jojosteez

Condensed into next post

jojosteez

@ksy, Yes, I did all the setup. Yes, everything I read says the machines overestimate calories burned. Oh in case it helps...I'm 30/male, 5ft7in, 211 lbs.

@WalkingAlong. I want to trust the HRM as research shows that's the most accurate way to tell Calories burned. And I know it's not exact, but as close as I can get.

Before using the HRM, I was using the silver contacts on the machines. And walking on the treadmill was consistently about half the Calories burned as a moderate pace (IIRC around 5mph according to the machine) on the elliptical. I would expect the elliptical to be higher as I have a higher heart rate and I sweat a lot more on it than walking on the treadmill.

@GetSoda, maybe my math is off. I'll give you some raw data. Here's the last 2 days of data

Elliptical - Moderate Pace (5mphish)
Duration: 32:31
Calories: 345
Avg HR: 130

Duration: 19:58
Calories: 201
Avg HR: 127

Treadmill - Walking 3-3.5mph
Duration: 18:03
Calories: 169
Avg HR: 122

Duration: 15:01
Calories: 173
Avg HR: 136

Those are all HRM readings. Before that I consistently did 20 min on the elliptical burned 200 Calories according to the elliptical machine using the silver contacts. HR would stay around 130-135. Then I would do 20 min walking on the treadmill and burn 100 Calories according to the treadmill using the contacts.

The HRM seems to be similar to the elliptical, but twice the treadmill.

Oh and also I noticed today the machines can read my chest strap and they were reading exactly what the FT4 was reading.

itsbasschick

if your heart rate and the time are the same, i believe the calories burned would be the same.

i tried this: http://www.calories-calculator.net/Calories_Burned_By_Heart_Rate.html
put in your age, weight, gender, a heart rate of 130 for 32 minutes and got
Calorie Burned(kCal): 397.689

which is higher than your elliptical is reading. the thing is that each HRM or calculator has its own algorithm, and it seems like no two are ever quite the same. if the HRM and elliptical are the same, i'd go with the HRM since ya gotta go with something.

jojosteez

@itsbasschick, Yes, I would want to go with the HRM as it should be the most accurate. MFP way overestimates and Ive read the machines do too. But I have been losing weight at a steady pace. 6 weeks and I'm 10 lbs down. It's been slow and steady so I trust what I have been doing is correct.

I find it hard to believe that the machines are underestimating my burn. And I'm afraid to log the HRM Calories if they are too high, since what I have been doing has been working. Only thing else I can think of is the HRM is faulty.

GetSoda

That's the problem with HRMs. They are based on what an athlete burns at a certain heart rate. And they are very, very optimistic.

jojosteez

Bump