BEWARE: Workout Machines and MFP Calorie Burn Estimates

DebraBuschman

First, I just want to disclaim that it's entirely possible within the realm of physics and science and all worldly knowledge that I'm an anomaly and that what I'm about to post applies to me and only me. I realize that.

However, I recently starting using the BodyMedia FIT (exactly like a Bodybugg, like on Biggest Loser) to track my calories burned. I was shocked to find out that when the stationary bike machine said I burned 343 calories, and MFP said it was 465 for the same work out, the FIT said I only burned 246 calories. Someone said it was because the BodyMedia FIT works, in part, by tracking movement and your arms (where you’re supposed to wear the device) don't move a lot on a stationary bike. SO I put the device on my calf next time. VERY similar result.

What does this mean? Did I get ripped off when I purchased the BodyMedia FIT? Well, I know I didn't get ripped off because my fiancé (who is a physician, and believes, based on what he has read and his own experience, the FIT is very accurate) let me use his, since he hasn't been using it.

I'm just throwing this out there, for all the people who keep screaming EAT YOUR EXERCISE CALORIES. I'm not arguing that one should not replenish when exercising, but just beware. It's difficult to figure out how many calories you've burned, exactly, no matter what method you use. That goes for HR monitors, as well. So, if you're diligently eating all your exercise calories, and you've hit a plateau, or are even gaining, you might consider whether or not you’re actually burning as many calories as you have been told you are. Whatever your source.

Good luck to everyone out there! We're all in this together.

AmberLiscous

i have a heart rate monitor and i was amazed at how much of a difference there was between it and what mfp says also....i only eat about half of my exercise calories if i eat any at all!!!!

nhaddad

I actually exercise for the fun of it...I never even log it although my exercise routine is massive...45 min of elliptical and 20 min of rowing....I never eat my exercise calories

muffindowd

I never post on the message boards, but I love to read them ;D. This made me come out of lurkdom. I totally agree with you!! The MFP database normally says I should burn almost 800 calories for my 45 minute elliptical workouts. The machine says I burn about 700, but I estimate it is a bit less than that. I only eat all of my exercise calories on the weekend and try to not eat too many on weekdays either...I just eat them when I feel like I need them and I am hungry for them!! Anyway on a normal evening my goal would be to keep some of my exercise calories and also replenish some of them with healthy eating!!

meribethd

I'd like to offer a different perspective on this. I have a Timex HRM and it consistently gives me a *higher* burn than MFP or any cardio machine gives me. I get 600+ for 45 min of turbo jam, 450 for 30 minutes of running/walking intervals, over 400 for 30 minutes on the elliptical. I don't know; I wonder if it's too high, but it has my weight in there, and is going off my heart rate. I work out really hard, so I guess the high burns are possible.

Anyway, just wanted to offer up my experience.

Cccaroline

I have to say I wouldn't be at all surprised if you're right. I often think mfp looks too generous, so I only eat some of my cals back, and try to listen to my body.

erinhale

Buy a HRM with a chest strap. They are the most accurate and the most reliable. I always tell my personal trainingclients to eat within 100 calories of thier net goal.

aflane

I only trust my HRM's readings. For example: Last nite, I did the stationary bike for 45 mins. The bike said I burned 280 cals. MFP said 740. My HRM said 410. I'll trust the mechanism that's actually strapped to my chest.

Brandicaloriecountess

I have seen a lot of people say this. I log my calories at what the machine says, however I do not eat my exercise calories so for me it isn't a big deal if it is giving me too much credit

FiremansWifey

I only add my exercise calories when I finish up my entry for the day.....I rarely eat any back...... since I started doing that I am losing weight again.....I was stuck at the same weight for a good while....

cammons

I am hopelessly devoted to my HRM, it has made a huge difference in how I view my activity. One thing I have noted is that when I use my inhaler (I have asthma during allergy season and take albuterol to keep me from keeling over) my heart rate is way high and in turn the calorie count is up too....caffeine does the same thing if I have it less than two hours or so before a workout.

Total newbie question, but is there a way to input my HRM calorie counts into MFP or do I have to use their estimates? (I thought I saw a place to put my own number in but can't find it anymore so I must have been mistaken.)

TCASMEY

Just like entering the time you can enter the number of calories burned.

cammons

Thanks much!

jewelzz

everybody burns diffrently acording to weight and level of fitness.I use my hrm everyday i workout and i never use mfp calculations but i do average out what the machine says and what my hrm says.

therealangd

The OP is correct. And to also add. Heart Rate Monitors are not 100% accurate either. Actual calories burned is based on the volume of oxygen consumed, not your heart rate.

bluellies

You know, I'd have to say I agree with your assessment. I'm not sure if MFP goes off of weight and height when it calculates it, or simply gives an average. There is a BIG difference in someone who is 304 and 5"10 vs someone who's 5'6 and 154.

I'm currently doing Dance Dance Revolution on my Wii, and I like it because I enter my weight into it. I've done a bit of research, and most professionals think it's fairly accurate. It also tells me how much I've burned with arm movements and feet, so that's cool. I still take it with a grain of salt--if my HR has been up the entire time and the cals look good I'll generally go with that, but if it seems high I'll just arbitrarily reduce them. I never even thought about getting a HRM that straps to my chest, that's an awesome idea and I'm going to look for them today.

Oh, and on a side note the cleaning calories are crazy! And burning 200 cals sitting on my butt riding my mower for an hour? Sure, I use my arms like crazy turning the dang thing, but really?

rocklion

A heart rate monitor is the most accurate way to track. Other than that it's just a guesstimate on anything online. I don't think it's necessarily bad to get an idea of how much you burned. But buyer beware, so to speak.

I mean honestly there's some things I see in the exercise portion that I think is nonsensical. At the same time, say for example you put in the eliptical trainer. You put in 30 minutes. It tells you that you burned 400 and something calories. But yet it doesn't take into consideration how hard you worked whether you were just barely working out or whether you were doing HIT.

No exercise is made the same. Best thing is a HRM.

DrewD2011

I always believe in my Polar HRM (probably a little too much!).

Yesterday, the calorie burn on the Life Fitness 95xi Elliptical read 640 after 60 minutes, the MFP.com says 733 and my FT80 said 801! My average HR was 141 (I am 44 - that is 80% of HR max) and it equated to 8.13 miles in distance on the unit (Kilimanjaro).

On a hard run day like that...I will try to leave a few of the exercise calories on MFP at the end of the day, but net is...on a hard workout like that...you must eat! Just focus on the right foods (high protein, low carb, low fat, complex grains). You will be motivated to make the right choices by remembering the effort you just put in.

Don't sweat the accuracy...just sweat and eat right!

hroush

This is why I split the difference and say to try to eat back half of what you burn, especially when you are trusting MFPs numbers.

SueInAz

Oh, and on a side note the cleaning calories are crazy! And burning 200 cals sitting on my butt riding my mower for an hour? Sure, I use my arms like crazy turning the dang thing, but really?

I have to wonder if the calories posted are how many calories you burn while doing that activity and not how many calories above and beyond your BMR you burned while doing it. In other words, if you sit on your butt and watch TV for an hour, you'll burn X amount of calories. If you ride your mower for an hour, you'll supposedly burn 200 calories. The big question in my mind is whether that 200 includes the X amount you would have burned just sitting around anyway. It shouldn't. Since we're adding it to our BMR amount, it should only be the amount of calories above and beyond our normal activity level's burn rate. If it's not, that would certainly explain some of the out of whack amounts I find.

DrewD2011

So today after 1 hour of elliptical...my HRM calorie burn read 764. After adding 2 hours of tennis...I added 1046. So after burning 1810 today and adding my allowed 1800...you really think that I am going eat 3610? I am about done for the day with eating and I have 1000 left. I am calling it a day. I ate well.