Huge Discrepancy in Cal Burned?

Lklambert3

I know machines are generally not super accurate at estimating calories burned. I ride a stationary bike with the HR monitor handles next to the seat. When I start, I select a program, put in my age, intensity level, weight and desired time. I don't put too much faith in what it tells me I am burning and therefore don't eat more than 1/3 of those calories back. That being said, I am OCD, and I wanted to know just how many I really was burning. I have a chest strap HRM, and I have been wearing that to compare the two. Throughout my workout, I will look, and they are both registering the exact same heart rate. Both are programmed with the same age, weight and fitness level... They are consistently WAY off. Last night as an example, I rode over 10 miles going 5.5-6 mph for 40 minutes. The bike states 550 calories burned... the chest strap says 272. What gives? I am more inclined to go with the strap, but that is a huge difference.
Oh, and I should also mention that when I walk around the neighborhood, and use the chest strap, the calculated calories burned is much closer to what Map My Walk is calculating and that isn't even using my HR. I am losing at a steady rate so really, I guess it doesn't matter but it is driving me crazy!
Thanks for your insight!

AllanMisner

Most machines don’t actually reflect your heart rate. They have their own estimates and assumptions. If you burn 500 calories in 30 minutes on one machine and 400 calories in 30 minutes on a different machine, which machine would you be inclined to use and/or buy? So, what is their motivation? To show more calorie burn. So, that calorie burn on machines is likely to be way, way over.

A HRM is better, but it still follows a set of assumptions that may or may not meet your usage. It is attempting to determine your level of effort based on an average. I’ll give you an example, I have a resting heart rate of 78. Do you think I’m burning more calories sitting still than someone the same sex, weight, age, body comp with a 58 resting heart rate? Nope. But a heart rate monitor would tell me I am.

Let go of your OCD on this one. They are all estimates (including calories in) and it is impossible to ever get to actuals. Just plug something reasonable and if your results are as planned, keep charging on. If you’re not seeing what you expect, tweak your estimates.

If you want to tap into your OCD, then count the number of calories that tick off on the machine per minute and try to get to a point where you can consistently hit a given pace. That neuromuscular control actually matters and will help you become more efficient and more fit.

Mr_Knight

HRMs aren't intended for walking - you're going to get a number roughly double your actual burn, if you use it like that. Just use this - it's simple, and will get you close enough:

net calories burned walking = body weight in pounds * miles walked * 0.3

Not following your biking scenario:

I rode over 10 miles going 5.5-6 mph for 40 minutes.

6mph for 40 minutes gets you 4 miles, not 10.

Lklambert3

Not following your biking scenario:

I rode over 10 miles going 5.5-6 mph for 40 minutes.

6mph for 40 minutes gets you 4 miles, not 10.
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This is true! Again, I was just watching what the machine was telling me as far as distance... and I think it has been lying to me!

Lklambert3

AllanMisner wrote: »

Most machines don’t actually reflect your heart rate. They have their own estimates and assumptions. If you burn 500 calories in 30 minutes on one machine and 400 calories in 30 minutes on a different machine, which machine would you be inclined to use and/or buy? So, what is their motivation? To show more calorie burn. So, that calorie burn on machines is likely to be way, way over.

A HRM is better, but it still follows a set of assumptions that may or may not meet your usage. It is attempting to determine your level of effort based on an average. I’ll give you an example, I have a resting heart rate of 78. Do you think I’m burning more calories sitting still than someone the same sex, weight, age, body comp with a 58 resting heart rate? Nope. But a heart rate monitor would tell me I am.

Let go of your OCD on this one. They are all estimates (including calories in) and it is impossible to ever get to actuals. Just plug something reasonable and if your results are as planned, keep charging on. If you’re not seeing what you expect, tweak your estimates.

If you want to tap into your OCD, then count the number of calories that tick off on the machine per minute and try to get to a point where you can consistently hit a given pace. That neuromuscular control actually matters and will help you become more efficient and more fit.

Thank you, this is very helpful. I will try to pick something in between and as long as I am seeing reasonable results, not worry too much about it. I appreciate you taking the time to explain that to me.