Wildly inaccurate calorie counts?

SomeoneSomeplace

Thank you all for your responses! I actually don't know a terrible amount of V02 Max or any of that. I am fairly out of shape at the moment. Not so much in the sense that I have a bunch of weight I absolutely NEED to lose but in the sense that after I tore my tendon I was out of pretty much ALL physical activity for 8 months minus some walking and very light biking. It was only very recently that I was cleared to get back to running and real working out, which means starting the grueling process of getting back in shape.

I actually wasn't aware until browsing the posts here that calories burned has more to do with heart rate. My HR runs high in general, I mean like around 100? Which is a combo of the fact that I'm on a couple medications and...well I'm not sure WHY I've just always been that way. My average heart rate was 167 while using above mentioned machine today, and it said I burned 800 calories in the one hour I was on it. The calculator that Jrabes provided said I burned 620 that seems fairly accurate although I have NO IDEA what my V02 max is I just put it in as 40.

I will definitely have to look into getting one of those heart rate monitors. I wasn't aware they gave you a calorie count as well. Again thank you all for your help!

dcpsu1992

Precor DOES overestimate caloric expenditure by about 20%. I worked on the manufacturing (equipment development) side of the business as product manager for 10 years. Although I worked for many companies, but not Precor, I did work with an engineering VP who had worked at Precor as the Dir. of Engineering. He told us that it was a marketing decision by Precor to overestimate the expenditure by 20%. It is a sneaky move, but it plays to the psychology of the user...if you see more calories burned on their machine, why would you use others...presses club to have more Precor and, i.e., improved Precor sales.

I am not saying that every other manufacturer is 100% accurate, I don't have proof of that. But my experiences with other units are more in line with what I would expect given my overall level of work. I am not the biggest fan of Precor, their machines are not that good in my opinion and am not stating the info above to be spiteful, I have no reason to be. I do love working out on the Arc Trainer by Cybex (the version movable arms) and if you get a chance to compare the two, you will find yourself working harder on the Arc (as measured by heart rate) but your level of percieved exertion will be lower. it is a great workout,

FatFinn320

She probably had her machine set to a higher resistance level. It makes a huge difference.

wilyumz1

I'm old (50) and while not fat or out of shape I'm about 25 lbs over where I want to be (165, at 5, 11 1/2")
I'm on a precor treadmill as I type this comparing my Harmon fitness watch / HR monitor to the treadmills cal burn indicator.
Today I have limited myself to 70-75% of max HR, and at the 45 min mark the machine says 287 cal burned, while my Harmon is at 485, true the Harmon has more data than age and weight but I don't know which is more accurate! I would suspect the Harmon as it's constantly monitoring heart rate

GetSoda

Use a HR monitor to get slightly different but still very inaccurate calorie burns

fixed

ArtistmanJ

Well fwiw, the Precor AMT's I use suggest I burn around 800 Calories in 50 minutes... I set it on "interval" with resistance set to 10 for low, and 20 for high. I then run the figure thru a net calorie calculator and it reduces it down to about 700-750 calories. I'm quite sure this is a very crude estimate at this point (and probably I simply got lucky) but with this method, plus MFP, I've gone from 220 lbs. to 180-183 lbs between mid September 2013 and now.

ArtistmanJ

Why? Because I like messing with this stuff! Interesting suggestion though. Naturally as you lose weight you have to recalculate the TDEE anyway (presumably down as you lose the weight) and my guess is that if you correctly log your exercise, MFP basically does that for you.

To me what matters is results. And for folks in general, if something in particular works for them, I'm all for it. I have a data-analysis background so as I actually find doing the calcs, both with calorie burn and food weight and stuff like that ... well, kind of fun. (no accounting for taste, right?)

Zjamai

As a general rule of thumb, for any moderate exercise you do that keeps your heart rate within the target zone, the average person (aka within your BMI) will typically burn about 100 calories every 10 minutes. I have a HRM that I use every time I exercise and give or take a few calories, I'm pretty much always in that 100 calories per 10 minute mark. This includes for aerobics, biking, running, hiking, elliptical and stair stepper. When I do intense group exercises like spin class or boxing, I find I'm more around 125 cals/10 minutes.

But if you don't want to invest in a HRM, this is an easy way to guesstimate how many calories you've burned during just about any moderate exercise. So unless you feel like you're going to topple over and/or throw up because you're exercising so hard (like I do in spin class!), you're probably right around 300 calories for your 30 minute exercise.

mfarmer88

I know this is an old post but.... I use the same machine on the fat burn setting (love it by the way!) and when I use my HR monitor, the machine tells me I burn less than my HR monitor does. So I have been taking sort of an average from the two of them, which is usually where MFP puts me. My HR monitor will say 600+ and the machine will say 300+, but MFP will be about 450... I also use the formula I found on a website of "For women, this is given by the equation C = (0.4472 x H – 0.05741 x W + 0.074 x A – 20.4022) x T / 4.184. C is the number of calories that you burned, H is your average heart rate, W is your weight, A is your age and T is the length of your exercise session in minutes. Assume that you’re a 28-year-old female weighing 146 pounds. Your average heart rate during an exercise session that lasted 36 minutes was 138 bpm. You burned C = (0.4472 x 138 – 0.05741 x 146 + 0.074 x 28 – 20.4022) x 36 / 4.184 = 301 calories."