How accurate are your exercise estimates? (Eric Thayer for The New York Times)When people with weight problems talk about their exercise and eating habits, many doctors and nutritionists don’t believe them. That’s because studies show that overweight people commonly underestimate the amount of food they’re eating.
But exercise habits appear to be a different story. New research shows that people with weight problems are far more tuned into how much they exercise than they are often given credit for.
In a study presented at the Obesity Society’s annual meeting, researchers from Temple University’s Center for Obesity Research and Education in Philadelphia found that obese women were more accurate in reporting their activity levels than overweight or normal weight women.
For 12 months, the researchers studied 280 normal weight, overweight and obese women whose average age was 47. The women were equipped with accelerometers, devices that measure physical activity, and asked how much they exercised at the beginning of the study, after three months and at 12 months. Notably, women who were normal weight or overweight, but not obese, had a more difficult time estimating their physical activity levels. But women who were obese — meaning they had a body mass index above 30 — came much closer to accurately estimating how much they were exercising.
Study lead author Tracy Oliver said that obese women are often considered “less credible” when they report their caloric intake, and that she expected they would also have a difficult time estimating their physical activity. She speculated that the opposite finding may be due to the fact that exercise and even low levels of physical activity may be particularly challenging for an obese person.
“They want to give themselves credit for every little bit engaged in due to the effort put forth,” she said.
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Interesting, I have to admit I would probably underestimate my calories and overestimate my exercise. The last quote there came off as kind of negative but maybe I’m reading too much into this.
— JKI don’t get the point of this. I must be having a fat brain day.
— StarIt is not specified what type of mis-estimation is the mode for the non-obese subjects (if indeed there is a statistically significant mode). The terminal two sentences of the article allude to non-obese subjects under-estimating (statistically speaking) their exercise, but no plain terms statement is made. That is, are non-obese subjects exercising more than obese subjects?
— guillaume fontaine de la tour dauteriveI was part of a study where I wore an accelerometer for 3 days, and I was surprised at what it told me about my activity level. I am a jogger, about 15 miles per week, and thought of myself as above average in my level of activity. To my surprise, the study estimate of my caloric expenditure put me squarely in the “average” activity range. I conclude that having a desk job and not walking to work cancel out the jogging more than I thought. So I guess I would have been categorized as one of those who overestimates my level of exercise. I am not overweight, so that would agree with the results of this study. On the other hand what it tells me is that probably the “average” person is sedentary to a greater degree than they realize.
— CatherinePossibly because exercise becomes much more difficult when one is obese or overweight. If it is that much harder for a person to manage a long walk or any more strenuous exercise, it would only make sense that he/she would be aware of every step!
— ShirleyThe crux of the question is whether or not obese people actually do enough exercise to offset their caloric intake.
Even though they may be better than non-obese subjects at reporting accurate exercise levels, they still overestimate, and they tend to underestimate food intake to a greater degree than non-obese subjects.
So, obese subjects may be more accurate on exercise reporting, but do they actually do more exercise than non-obese subjects? NO.
The whole tenor of this article is to send the message that obese subjects are not at all responsible for their obesity. This is not productive.
Some will say it is all genetics, but how come, as a nation, we are twice as fat as we were 20 years ago? Genes don’t change fast enough to account for that fact.
We are simply eating more and exercising less. Period.
— jackDid the overweight and normal weight women over- or under-estimate their exercise? Or was there no trend?
— JenHuh.
Fascinating.
— ClotarioIn all fairness, numerous studies have demonstrated that NORMAL weight people underestimate their intake by 1/2 and OVERWEIGHT people underestimate their intake by at least 1/2.
This is interesting regarding the exercise. The other question if relative intensity. And unfortunately, it is control of intake that will have the effect initially in a weight loss/control program. The exercise component is much more important in the maintenance phases.
The major misconception is that any or 30 minutes of any exercise will make up for a multitude of indiscretions. One of the easiest ways to see is look at the nih Portion Distortion quiz - how much raking, vacuuming, weight lifting, etc does it take to work off that bagel, fries, etc etc. (I am assuming that the NYT doesnt like outside links. Just google “Portion Distortion Quiz” and choose the nhlbi.nih.gov link. Your tax dollars at work.)
— susanSo, does this mean that “normal” weight people will be seen as less credible than the “obese” when reporting their level of physical activity?
— DRI also don’t get what this study means. Weight loss experts say that people who keep a food diary lose more weight and keep that weight off longer than people who don’t.
Then, do people who keep exercise diaries also exercise more? Maybe it’s the hockey mom in me, but I’m confused.
— PariFascinating. Another explanation might be that lower-weight women are actually doing much more physical activity than they think they are or give themselves credit for. Even if they’re not “exercising,” maybe they’re just walking more, on their feet more at work, scurrying around after children, etc, which all adds up. It’s been shown that even fidgeting burns a significant amount of calories in the long term.
— Emily B.The sad truth is this: the best excercise on earth is to push away from the table. Excercise for most people will not take the place of dieting. jennifer
— jennifer“She speculated that the opposite finding may be due to the fact that exercise and even low levels of physical activity may be particularly challenging for an obese person.
“They want to give themselves credit for every little bit engaged in due to the effort put forth,” she said.”
I don’t usually comment, but I think Ms. Oliver’s observation quoted here misses the mark. Perhaps overweight people obsess over how much exercise they get more than most average or under weight people. (I’m excluding under/average weight people who are fixated on exercise and diet from this generalization). If you are naturally an average weight person then you presumably don’t constantly worry about how much you eat and how often you exercise. A naturally average weight person would not have to spend as much time as an overweight person thinking about these things. Therefore an average/under weight person would not be as able to accurately report exactly how much time he/she spends exercising.
— MeganFrom what I’ve read, everyone underestimates how much they eat. The infamous “neverending bowl” experiment wasn’t targeted only at obese people.
I think this report just a sideways means of saying that people — also meaning health professionals — unfairly flog fat folk for whatever reasons. And that they are wrong.
— Janet VI agree about that last line, JK.
— cheekyThe findings don’t surprise me, but it’s good to have some evidence to go on.
I’ve definitely been on the receiving end of the assumption that I can’t possibly be as physically active as I say I am. The first time I went to see my primary care provider, she asked about my exercise routine and I told her honestly (60-90 minutes a day, everyday, some days more, a combination of strength, flexibility, agility, and cardio training) by her reaction I could tell that she thought I was “padding my resume.” She continued to tell me about the minimum recommendations, which I exceed by far. Then she took my pulse and blood pressure - and immediately said “wow, you’re in good shape, you really must exercise a lot.” After that point, she has never doubted my answers, and we have a very good patient/doctor relationship.
I’ve also had others ask if I’m feeling alright upon taking my pulse (resting is usually around 55 bpm), even though I’m not presenting any other signs that low heart rate would be a problem. If you see a person with warm hands, full color in their face, clear/deep/even breathing and their pulse is low, why assume illness rather than health?
— MPMakes reasonable sense on a socialogical level. Obese individuals looking to lose weight want/need others to think they are trying their hardest to, reporting less calories and excercise demonstrative of high effort. If they are unable to lose weight, it has to be some other fault than their own will to. (even if it often is) For them to admit high calorie and shakey excercise would mean they didn’t care and alienate them further from a judgmental society.
Now average or less than average weight people looking to lose weight can report any calories they want from nothing to 30 pizzas a day– because they can and are somehow gifted with high metabolism and will receive praise no matter what. Yet reporting excercise is tough because no effort was needed to maintain this average weight and it is inconsequential in their life.
— blink“women who were obese — meaning they had a body mass index above 30 — came much closer to accurately estimating how much they were exercising”
Provacative theory or a no-brainer:
It is easier to estimate ZERO or little activity. (”I’ve on the couch all day!”)
(Tara, did they mention how much activity were documented in each group?)
— NYCRealistI too was curious about the amount of activity reported by both groups believing that it was easier to report on little or no activity than to attempt to calculate a daily amount of activity for people who aren’t sedentary.
I, myself, do a 55-60 minute cardio/strength/flexibility workout every day and walk my dogs for at least an hour each day. I tend to my flower beds, cook a fair amount, and have two flights of stairs to run up and down, frequently lugging full baskets of laundry.
If asked how much exercise I got each day, I would reply 55-60 minutes. But if I were asked how much time I spent walking, doing dishes, folding laundry, gardening, standing, etc. my “activity level” would increase dramatically even though I don’t consider any of that exercise.
— Laurice“…low levels of physical activity may be particularly challenging for an obese person.”
No, see, this is phrased inaccurately. A level of physical activity that is low for a person who weighs 150 pounds is not low but high for a person who weighs 300 pounds. Try it! Pick up 150 pounds and walk down the hall! You might be out of breath! Would that be surprising? No! But if you WEIGH 150 extra pounds, the 150 pounds don’t count. That’s ’cause, confronted by adipose tissue, doctors toss elementary reason right out the window.
“’They want to give themselves credit for every little bit engaged in due to the effort put forth’”
— Nom, nom, nom!They probably want to accurately report what they’re doing so as to contribute good data to the experiment. But they may as well not waste their time, given that they’re fat and therefore their doctor has done tossed elementary reason right out the window.
Taubes proves in Good Calories, Bad Calories that exercise will not help you lose weight, as it increases hunger at least as rapidly (and usually more rapidly) than it burns calories. The science is irrefutable, yet the “exercise more” canard remains ubiquitous.
— TomWhen I worked at a gym, there was a member there that was obese and she went to the gym every night. She would walk on the treadmill while she ate her ‘m&m’s’. I was shocked the first time I saw her, because what a waste of time! Surprise, surprise she didn’t lose any weight.
— LisaMost posters are missing the point. This type of study is NOT intended to assess how much exercise various categories of people do, nor is it intended to ‘judge’ anyone.
Very many epidemiological studies are based on ’self report’. It is essential that researchers understand the extent to which various ‘types’ of subjects report accurately, so that research ‘findings’ can be interpreted in some meaningful way. The use of a ‘gold standard’ measure (and objective one, used in a prospective study, such as the use of an accelerometer) is best, but it’s also important to know how close to that ‘gold standard’ lesser quality measures are. Prospective trials are more expensive and time consuming than retrospective observational studies, so epidemiologists often use the latter when developing hypotheses. It is standard practice to run the type of study described in this post in order to calibrate various measurement mechanisms - including self-report. Trying to read more into this type of study than that is a fool’s errand.
— CathyAnd to poster Laurice: the study is quoted as referring to the outcome as ‘activity level’, not exercise. Typically, this is determined by using a standard questionnaire, which asks about explicit ‘exercise’, but also asks about household tasks, walking to the corner store, caring for children, etc. It also asks questions about the type of work one does. Activity is then assessed using standard, calibrated formulas that assign a certain number of metabolic units to each activity/duration. I assume this study used such an instrument as part of the ’self report’ based on the use of the term ‘activity level’.
— Cathy