baffled -- Good article. I think we all have to kind of figure it out for ourselves. I know my HRM consistently says I've burned about 60-65% of the calories the elliptical machine says! My husband and I have started to call the elliptical "calories" "energy units burned" as they are just a random number...
I enter my food and exercise minutes in nutridiary. I do the exercise more to track the minutes, I figure the calorie estimates are off. Nonetheless, when generate a report over time that estimates my weight loss (or lack thereof) it's pretty accurate with reality. That is, over 10 weeks I might lose 3 pounds, and nutridiary might tell me that I should have lost 2.5.
I suspect there's lots of "error" in a number of places and that, for me, it averages out to a decent guess. I also suspect I might be unusual in that regard.
I do know I read a lot of people who probably think they are burning more calories than they really are!
My 5 C's of healthy living: Commitment to conscious control, with the understanding that choices have consequences
One thing that the article doesn't mention that I've thought would make a big difference in calories burned is body fat percentage. Since muscle burns more calories than fat, if two people were working out at the same intensity, both weighed the same, and achieved the same heart rate but one had a lower percentage of body fat than the other, wouldn't the one with the lower body fat percentage be burning more calories? Or does that rule only apply to your resting metabolism? I've never seen any machine or calculator that takes into account body fat percentage when computing the number of calories burned for an exercise. Is it because it doesn't matter, body fat percentages are too inaccurate, or most people don't know their body fat percentage?
My guess would be that a. most people don't know their body fat percentages, and b. the machine manufacturers aren't using anything like a standardized formula to determine calories burned, so adding another variable would be beside the point. I have wished, however, that my Polar HRM allowed me to enter my bf%. I don't see why it doesn't, actually. Anyone know if the fancier Polar models (I have the F4) allow you to enter body fat?
That's a good one! An organization - I think it was ACE (American Council on Exercise) - did an analysis of a half-hour Curves circuit and found that it burnt something like 132 calories. Which is not shabby for a half hour of exercise, but it's sure not 500 calories! I'll see if I can find the citation.
Start: 257 - June 1, 2001
Goal: 135 - May 12, 2002
Size 22/size 4
Apologies to Curves -- it's actually 184 calories for a half-hour workout, according to ACE:
The study found that the 30-minute Curves workout, including five minutes of stretching and cool-down, burns an average of 184 calories making it a good “moderate-intensity” workout for those who are not very active.
Women should also avoid the temptation to turn their Curves workouts into a social hour. Researchers noted some of the women in the study were more focused on chatting during their workouts than exercising.
Doesn't chatting burn calories?
Start: 257 - June 1, 2001
Goal: 135 - May 12, 2002
Size 22/size 4
Good article although one thing in there bugs me where it says that you shouldn't eat more just because you exercise.
One of the reasons I've been losing is because I'm not putting all my eggs in one basket so to speak. I exercise 6 days a week therefore I can eat a bit more, which makes sticking to plan so much easier.
If you didn't put activity level into consideration when choosing your calorie level thats like saying the home bound sedentary person should be eating the same as they would if they were doing 2 hours of exercise a day. You'd lose steam awfully quickly if were doing all that exercise on 1000 calories or whatever.
I think the key is not using it as a free for all pass since we know there are over estimations going on with exercise and often under estimations on calorie intake. But I don't think it's smart to make people feel guilty for increasing calories just a tad when increasing activity.
Half Iron Triathlete as of 7/2010
Training for Ironman Wisconsin!
I address the variable in calories burned with a few tactics.
First, I always enter my goal weight in the treadmill, not my current weight. Same goes for the 'calories burned per activity' site I use. There is currently a 75 lb difference in those two, and I recognize that as I near my goal weight I will have to take only a percentage of the calories burned, but for now, it's working. I only count planned exercise, or significant efforts like snow shovelling.
I also enter my activity level in my calorie tracking program as very sedentary, thereby low-balling my 'calorie budget'. I ignore the number of times I run up and down the stairs doing this and that. I enter everything I eat into that programme, and if I have to guesstimate a portion (like when I'm out) I over-estimate. So far, I have lost 15 lbs in 6 weeks. At my current weight, that is about right on track.
I also have a Tanita scale that measures bodyfat %. I used my info in various calculations and found that the variance was fairly small, and pretty much in line with my calorie-tracking programme.
Tanita now makes scales that measure weight, body fat and water and can give a fairly accurate baseline BMR. I have no idea how much they cost, though.
There are so many variables to consider when calculating calorie burn that it is only possible to generalize. It is better to focus on exercising frequently - at least five days a week, at least 30 minutes per day. Whatever exercise you do, if you do it on that basis of that frequency you will reap the benefits; increased calorie burn, increased metabolism, extra muscle tone, and an improvement in general fitness.
I always take it with a grain of salt, and I definitely don't make a habit of eating the calories I burn off with exercise. I won't feel as bad if I go over a bit if I did exercise, but I just see it as more fat I could be getting rid of so unless I just have a really hungry day, I try to leave it at that. I'm not always very successful, but it's a goal anyway
I think someone mentioned that our bodies become efficient with the exercises we do, and I can definitely see that. I'm doing some strenght/yoga exercises on the Wii Fit as well as the free step. I'm still working up a sweat and went from 30 minutes to 60 minutes, though sometimes I do around 40-45 because the 30 minutes was getting to be too easy for me. I'm not sure what I'm going to do once 60 minutes isn't as easy, but ultimately I think I'd like to join a gym and do some classes/weight training/machines/etc.
However. I would point out that you should figure out (via Harris-Benedict or other valid calculator) what your energy expenditure is (i.e., what you could eat if you wanted to maintain your current weight * activity factor) and then drop down 20-30%. What you exercise is weighed in (so to speak) by the activity factor (1.3 for moderately active, 1.55 for more active, etc.) So what you eat v. what you exercise should be already adjusted. (I hope that makes sense)
What's really important is to make sure your assessment of your activity level is honest. That's what I've been doing and I'm seeing a steady 2#/week drop. At the same time, I'm monitoring bf% so I know WHAT I'm losing.