5 ms·

Weighing the Evidence on Exercise

33 points by rams 16y ago

jamesmontalvo3 16y ago
"Take in fewer calories than you burn, put yourself in negative energy balance, lose weight" Join a fitness/nutrition website to provide accountability (and to educate you that the presumably healthy food you're eating is actually highly caloric).
superjared 16y ago
The article explains a basic tenet of metabolism: balancing caloric intake with exercise is the key to weight loss. However, it does not mention much about the health benefits of exercise nor the importance of eating healthy foods, which is unfortunate because one's health is more important than simply losing weight.
- mberning 16y ago
  I agree. I think many people make the mistake of looking at exercise as simply a means to an end: losing weight. It has so many other benefits like helping to control blood pressure, improved mood, etc. To me these are more important than simply maintaining a pleasing number on a scale. I'm overweight according to the BMI and other measures, but I strength train and do cardio regularly. My blood pressure, cholesterol, triglycerides, testosterone, etc. are all perfect.
chegra84 16y ago
"“In general, exercise by itself is pretty useless for weight loss,” says Eric Ravussin, a professor at the Pennington Biomedical Research Center in Baton Rouge, La., and an expert on weight loss. It’s especially useless because people often end up consuming more calories when they exercise." Study, have shown that if your energy expenditure and take-in is the same as dieting, exercise can produce the same results. I have this hypothesis that it is psychologically easier to exercise off weight than to restrict your diet below maintenance. Reason why: 1. Less willpower for exercise. Once you are on the treadmill it's easy to continue, while for dieting you will need to control yourself for at least 8hrs. So, comparing 15mins of control for getting started to exercise to 8hrs of control to diet, exercise significantly better. 2.Exercise release endorphins, ie you will be happier after exercising. Dieting leaves you irritable and tired. 3. Exercise builds metabolism, so you will burn at rest[not as much as they would have you believe in some books]. Dieting slow metabolism. 4. At moderately high intensity exercise can reduce appetite. Drawbacks to exercise: 1) Takes alot of time. Walking at 4mph for 60mins only burns 340 calories for a 150pound man[or something like that]. So, in essence 3hrs of exercise by walk a day will burn 2 pounds a week[provided that you follow a maintenance diet]
- jamesbritt 16y ago
  Re Will power: I've stopped buying crap food (with some rare allowances). If I do not have it in the house, I cannot eat it. The willpower issue comes up once a week while shopping, and I'm not in the mood for junk food while shopping, so it's easier to not buy it than it would be to not eat it were it in the house. Exercise, though, requires much more deliberate action, and more than once a week. Once I'm out running it's OK, and keeping going is not a problem. It's the initial choice of go running or sit on my ass and drink coffee in the morning. Dicking around seems to have a a magical sway over me. :( Despite having almost completely slagged off on exercise over the last few months I'm still just below 180lbs (down from 210 last summer), and I'm sure this is because of my diet. I still need to exercise least my body turn to complete goo, but for weight loss I find it much easier to just not have bad food in the house.
  - chegra84 16y ago
    You are telling me that you eat 1000 calories less than required and you aren't tempted to break the diet? :)
    - narag 16y ago
      I can speak for myself. I've lost 15 kg since last summer, not feeling hungry at all, so it's not "1000 calories less than required", at least not what my apetite requires :) In fact, I don't feel like I'm doing a diet, it hasn't been my intention at all. I simply started eating a lot more fruit, in part by accident (didn't know how delicious is pinneaple), in part for convenience (apples are easy to bring in the backpack, salads come now in cheap bags), in part because of my son (he loves orange juice at all times, I eat the ones that remain). Also it's better to avoid prepared food. I still eat a lot of pasta and meat (I've just enjoyed a 250 g steak) and enough seafood. The only significant casualties are bread (only with meat or fish) and cheese... like Hurley said "everybody likes cheese", but it does no good to me :-( I agree that exercise is great. But I live far from sea, so I can't windsurf most of the year, and jogging bores me to death. Once year ago I went to the gym and it was really good, but it made me really hungry, so it didn't help with weight lose. In my twenties it was different, but at the time it was much more intense than what I can do now.
Maro 16y ago
Exercise a lot. It's easy to reach Marathon levels, and I guarantee you'll loose weight.
gluu 16y ago
Analyzing my own eating habits, I think that the light, constant exercise factor is representative of regulated behavior that causes people to maintain weight. That is, exercising regularly is a reflection of a person's lifestyle (not a stressed out entrepreneur) that coincides with maintaining a healthy weight, as well as helping a person regulate their behavior (the good feelings and satiation make it easier to not have events where you eat crap).
alexyim 16y ago
It seems like the article is making exercise more mysterious than it is. From what I've read, scientists seem to be more knowledgeable than the state of confusion this article is giving out. The benefit of exercise in terms of weight loss is that it increases your resting metabolic rate (RMR). So the greatest caloric expenditure is often not during the exercise activity itself. I used to think that it's impossible to burn off the calories eaten from a burger. Now I know better. Of course, exercise is only effective if your diet complements it. It's not either or, it's both. Both contribute to a net caloric deficit or surplus, creating weight change. They also don't go into enough detail about the types of exercises. HIIT and weightlifting are particularly effective towards increasing RMR.
- c0riander 16y ago
  I think a great deal of the confusion the article is conveying is not so much about the effect of exercise on metabolism and body composition, but rather its effect on appetite. One of the reasons that we're starting to hear obesity specialists back away from advocating the "moderate-vigorous exercise" as part of a weight-loss plan is because of the things this article brings up: in some people (mostly women), starting an exercise regime spikes appetite and makes it extremely difficult to stick to a calorie-controlled/restricted diet. Thus, even if the RMR increases, it seems the body is insisting calorie intake increase as well -- and I think that's where the confusion they are portraying is mostly stemming from: is it responsible to advocate moderate-vigorous exercise to the obese as part of a weight-loss plan, or is that setting them up to fail? (It seems clear that exercise as part of a weight-maintenance program tends to be beneficial.)
jules 16y ago
Is there good, accessible science (not the opinion of an "expert") about - What kind of exercise is good for what (e.g. short intense or long light)? - How quickly does performance increase? What causes better performance? - Why and how quickly does muscle tissue form? - Does lung volume increase? - What happens to your heart? - What happens to your veins? - How much exercise? - How does eating affect exercise? E.g. if you are losing weight, will your body still make roughly as much new muscle tissue? - Why is it that I get sore more quickly and run more slowly when I haven't eaten enough, even in the first few minutes of running when all the energy is still coming from stuff stored in muscles? I think the answers to these questions would be very valuable to individuals as well as society as a whole.
dreeves 16y ago
Somewhat orthogonal but apropos: http://lesswrong.com/lw/am/how_a_pathological_procrastinor_can_lose_weight/ http://lesswrong.com/lw/am/how_a_pathological_procrastinor_c...
latortuga 16y ago
"Take in fewer calories than you burn, put yourself in negative energy balance, lose weight,” says Braun, who has been studying exercise and weight loss for years." Weight loss is not this simple - this kind of article enrages me. Everyone wants it to be an easy equation. Low carbohydrate/high fat diets are wildly successful despite not having to monitor calories. All calories are not created equal and simply eating less does not lead to long term weight loss, it leads to hunger. I know many have talked about this idea on HN before, but in case you missed it, an excellent, eye-opening read is Gary Taubes' book, Good Calories Bad Calories - http://www.amazon.com/Good-Calories-Bad-Controversial-Science/dp/1400033462 http://www.amazon.com/Good-Calories-Bad-Controversial-Scienc...
- briandoll 16y ago
  Huge +1 for 'Good Calories, Bad Calories'. Read this and you'll change your bad eating habits immediately. Exercise is very important, but body composition changes come from nutrition. (After changing how I ate, I lost 70# in 6 months and have kept that same weight for 2 years, more info for the curious: http://emphaticsolutions.com/2009/01/12/clean-eating-how-I-make-it-work.html http://emphaticsolutions.com/2009/01/12/clean-eating-how-I-m...)
  - tokenadult 16y ago
    I lost 70# in 6 months How young were you when you had seventy pounds that you could afford to lose?
    - briandoll 16y ago
      I was 30 years old, 6' 1" and weighed 250#. 6 months later I weighed 180#. After working out more I'm up to 185# with 9.9% body fat, which is a weight I've sustained now for 2 years.
- Darmani 16y ago
  Yes, burning fat really is that simple. A lot of this gets muddied from other factors, such as how various diets affect body composition, water retention, and appetite (supposedly much of the success of low carb diets comes from increased protein intake, which reduces hunger), and weight is hardly the only aspect of health, but the basic energy in minus energy out equation is true for humans. See http://www.bodyrecomposition.com/fat-loss/is-a-calorie-a-calorie.html http://www.bodyrecomposition.com/fat-loss/is-a-calorie-a-cal...
tokenadult 16y ago
I think after reading all the comments, I still have one more bit to add. The submitted article refers to GENERAL effects of exercise that are observable in current population studies. It does seem to be well established that human beings are adapted to balance their eating with their activity, thus human beings who don't live in conditions of food scarcity may not be likely to lose weight if they increase their level of physical activity. That said about the general tendency, my observation of the effect of exercise is that it makes me more cheerful, and allows me to substitute the pleasure of fresh air and sunshine and movement for the pleasure of eating. So at least on my part, I have been able to reduce weight (I didn't have a lot to lose at my heaviest) by being more consistent about exercise. These days, there are times when I feel a vague discomfort that I might formerly have treated by eating a snack that I now treat by talking a walk outside. More exercise AND less eating is sure to result in weight loss over time.
chegra84 16y ago
As one of the article says "both sides of the argument can bring lots of data to thet table in support of their contentions." I think scientist should be leading the charge on this. Everybody seem to have their own book or point of view to peddle.
wendroid 16y ago
see also http://www.sethroberts.net/about/whatmakesfoodfattening.pdf http://www.sethroberts.net/about/whatmakesfoodfattening.pdf
Aron 16y ago
I find it interesting how quickly the body appears to decondition when you stop exercising. I suspect the consensus is that this is intended to lower basal metabolism, which would make one better adapted to a food scarce environment. However, if you consume high quantities of food, the body still deconditions. It ignores this data. So what is the true reason why the body prefers a state of lower conditioning? Even if I lazed around for months in my cave, I'd still want to be at maximum ready for when a neighboring tribe appeared or if I suddenly needed to increase exertion for food. I find it plausible that exercise has costs that are being overlooked. I'm always impressed by the longevity of academic-types I find in wikipedia, who I presume don't run marathons often. NFL players have extremely low lifespans. Marathon runners tend to have higher rates of heart damage.

33 points by rams 16y ago

"Take in fewer calories than you burn, put yourself in negative energy balance, lose weight" Join a fitness/nutrition website to provide accountability (and to educate you that the presumably healthy food you're eating is actually highly caloric).

superjared 16y ago

The article explains a basic tenet of metabolism: balancing caloric intake with exercise is the key to weight loss. However, it does not mention much about the health benefits of exercise nor the importance of eating healthy foods, which is unfortunate because one's health is more important than simply losing weight.

mberning 16y ago
I agree. I think many people make the mistake of looking at exercise as simply a means to an end: losing weight. It has so many other benefits like helping to control blood pressure, improved mood, etc. To me these are more important than simply maintaining a pleasing number on a scale. I'm overweight according to the BMI and other measures, but I strength train and do cardio regularly. My blood pressure, cholesterol, triglycerides, testosterone, etc. are all perfect.

chegra84 16y ago

"“In general, exercise by itself is pretty useless for weight loss,” says Eric Ravussin, a professor at the Pennington Biomedical Research Center in Baton Rouge, La., and an expert on weight loss. It’s especially useless because people often end up consuming more calories when they exercise." Study, have shown that if your energy expenditure and take-in is the same as dieting, exercise can produce the same results. I have this hypothesis that it is psychologically easier to exercise off weight than to restrict your diet below maintenance. Reason why: 1. Less willpower for exercise. Once you are on the treadmill it's easy to continue, while for dieting you will need to control yourself for at least 8hrs. So, comparing 15mins of control for getting started to exercise to 8hrs of control to diet, exercise significantly better. 2.Exercise release endorphins, ie you will be happier after exercising. Dieting leaves you irritable and tired. 3. Exercise builds metabolism, so you will burn at rest[not as much as they would have you believe in some books]. Dieting slow metabolism. 4. At moderately high intensity exercise can reduce appetite. Drawbacks to exercise: 1) Takes alot of time. Walking at 4mph for 60mins only burns 340 calories for a 150pound man[or something like that]. So, in essence 3hrs of exercise by walk a day will burn 2 pounds a week[provided that you follow a maintenance diet]

jamesbritt 16y ago
Re Will power: I've stopped buying crap food (with some rare allowances). If I do not have it in the house, I cannot eat it. The willpower issue comes up once a week while shopping, and I'm not in the mood for junk food while shopping, so it's easier to not buy it than it would be to not eat it were it in the house. Exercise, though, requires much more deliberate action, and more than once a week. Once I'm out running it's OK, and keeping going is not a problem. It's the initial choice of go running or sit on my ass and drink coffee in the morning. Dicking around seems to have a a magical sway over me. :( Despite having almost completely slagged off on exercise over the last few months I'm still just below 180lbs (down from 210 last summer), and I'm sure this is because of my diet. I still need to exercise least my body turn to complete goo, but for weight loss I find it much easier to just not have bad food in the house.
- chegra84 16y ago
  You are telling me that you eat 1000 calories less than required and you aren't tempted to break the diet? :)
  - narag 16y ago
    I can speak for myself. I've lost 15 kg since last summer, not feeling hungry at all, so it's not "1000 calories less than required", at least not what my apetite requires :) In fact, I don't feel like I'm doing a diet, it hasn't been my intention at all. I simply started eating a lot more fruit, in part by accident (didn't know how delicious is pinneaple), in part for convenience (apples are easy to bring in the backpack, salads come now in cheap bags), in part because of my son (he loves orange juice at all times, I eat the ones that remain). Also it's better to avoid prepared food. I still eat a lot of pasta and meat (I've just enjoyed a 250 g steak) and enough seafood. The only significant casualties are bread (only with meat or fish) and cheese... like Hurley said "everybody likes cheese", but it does no good to me :-( I agree that exercise is great. But I live far from sea, so I can't windsurf most of the year, and jogging bores me to death. Once year ago I went to the gym and it was really good, but it made me really hungry, so it didn't help with weight lose. In my twenties it was different, but at the time it was much more intense than what I can do now.

Maro 16y ago

Exercise a lot. It's easy to reach Marathon levels, and I guarantee you'll loose weight.

gluu 16y ago

Analyzing my own eating habits, I think that the light, constant exercise factor is representative of regulated behavior that causes people to maintain weight. That is, exercising regularly is a reflection of a person's lifestyle (not a stressed out entrepreneur) that coincides with maintaining a healthy weight, as well as helping a person regulate their behavior (the good feelings and satiation make it easier to not have events where you eat crap).

alexyim 16y ago

It seems like the article is making exercise more mysterious than it is. From what I've read, scientists seem to be more knowledgeable than the state of confusion this article is giving out. The benefit of exercise in terms of weight loss is that it increases your resting metabolic rate (RMR). So the greatest caloric expenditure is often not during the exercise activity itself. I used to think that it's impossible to burn off the calories eaten from a burger. Now I know better. Of course, exercise is only effective if your diet complements it. It's not either or, it's both. Both contribute to a net caloric deficit or surplus, creating weight change. They also don't go into enough detail about the types of exercises. HIIT and weightlifting are particularly effective towards increasing RMR.

c0riander 16y ago
I think a great deal of the confusion the article is conveying is not so much about the effect of exercise on metabolism and body composition, but rather its effect on appetite. One of the reasons that we're starting to hear obesity specialists back away from advocating the "moderate-vigorous exercise" as part of a weight-loss plan is because of the things this article brings up: in some people (mostly women), starting an exercise regime spikes appetite and makes it extremely difficult to stick to a calorie-controlled/restricted diet. Thus, even if the RMR increases, it seems the body is insisting calorie intake increase as well -- and I think that's where the confusion they are portraying is mostly stemming from: is it responsible to advocate moderate-vigorous exercise to the obese as part of a weight-loss plan, or is that setting them up to fail? (It seems clear that exercise as part of a weight-maintenance program tends to be beneficial.)

jules 16y ago

Is there good, accessible science (not the opinion of an "expert") about - What kind of exercise is good for what (e.g. short intense or long light)? - How quickly does performance increase? What causes better performance? - Why and how quickly does muscle tissue form? - Does lung volume increase? - What happens to your heart? - What happens to your veins? - How much exercise? - How does eating affect exercise? E.g. if you are losing weight, will your body still make roughly as much new muscle tissue? - Why is it that I get sore more quickly and run more slowly when I haven't eaten enough, even in the first few minutes of running when all the energy is still coming from stuff stored in muscles? I think the answers to these questions would be very valuable to individuals as well as society as a whole.

dreeves 16y ago

Somewhat orthogonal but apropos: http://lesswrong.com/lw/am/how_a_pathological_procrastinor_can_lose_weight/ http://lesswrong.com/lw/am/how_a_pathological_procrastinor_c...

latortuga 16y ago

"Take in fewer calories than you burn, put yourself in negative energy balance, lose weight,” says Braun, who has been studying exercise and weight loss for years." Weight loss is not this simple - this kind of article enrages me. Everyone wants it to be an easy equation. Low carbohydrate/high fat diets are wildly successful despite not having to monitor calories. All calories are not created equal and simply eating less does not lead to long term weight loss, it leads to hunger. I know many have talked about this idea on HN before, but in case you missed it, an excellent, eye-opening read is Gary Taubes' book, Good Calories Bad Calories - http://www.amazon.com/Good-Calories-Bad-Controversial-Science/dp/1400033462 http://www.amazon.com/Good-Calories-Bad-Controversial-Scienc...

briandoll 16y ago
Huge +1 for 'Good Calories, Bad Calories'. Read this and you'll change your bad eating habits immediately. Exercise is very important, but body composition changes come from nutrition. (After changing how I ate, I lost 70# in 6 months and have kept that same weight for 2 years, more info for the curious: http://emphaticsolutions.com/2009/01/12/clean-eating-how-I-make-it-work.html http://emphaticsolutions.com/2009/01/12/clean-eating-how-I-m...)
- tokenadult 16y ago
  I lost 70# in 6 months How young were you when you had seventy pounds that you could afford to lose?
  - briandoll 16y ago
    I was 30 years old, 6' 1" and weighed 250#. 6 months later I weighed 180#. After working out more I'm up to 185# with 9.9% body fat, which is a weight I've sustained now for 2 years.
Darmani 16y ago
Yes, burning fat really is that simple. A lot of this gets muddied from other factors, such as how various diets affect body composition, water retention, and appetite (supposedly much of the success of low carb diets comes from increased protein intake, which reduces hunger), and weight is hardly the only aspect of health, but the basic energy in minus energy out equation is true for humans. See http://www.bodyrecomposition.com/fat-loss/is-a-calorie-a-calorie.html http://www.bodyrecomposition.com/fat-loss/is-a-calorie-a-cal...

tokenadult 16y ago

I think after reading all the comments, I still have one more bit to add. The submitted article refers to GENERAL effects of exercise that are observable in current population studies. It does seem to be well established that human beings are adapted to balance their eating with their activity, thus human beings who don't live in conditions of food scarcity may not be likely to lose weight if they increase their level of physical activity. That said about the general tendency, my observation of the effect of exercise is that it makes me more cheerful, and allows me to substitute the pleasure of fresh air and sunshine and movement for the pleasure of eating. So at least on my part, I have been able to reduce weight (I didn't have a lot to lose at my heaviest) by being more consistent about exercise. These days, there are times when I feel a vague discomfort that I might formerly have treated by eating a snack that I now treat by talking a walk outside. More exercise AND less eating is sure to result in weight loss over time.

chegra84 16y ago

As one of the article says "both sides of the argument can bring lots of data to thet table in support of their contentions." I think scientist should be leading the charge on this. Everybody seem to have their own book or point of view to peddle.

wendroid 16y ago

see also http://www.sethroberts.net/about/whatmakesfoodfattening.pdf http://www.sethroberts.net/about/whatmakesfoodfattening.pdf

Aron 16y ago

I find it interesting how quickly the body appears to decondition when you stop exercising. I suspect the consensus is that this is intended to lower basal metabolism, which would make one better adapted to a food scarce environment. However, if you consume high quantities of food, the body still deconditions. It ignores this data. So what is the true reason why the body prefers a state of lower conditioning? Even if I lazed around for months in my cave, I'd still want to be at maximum ready for when a neighboring tribe appeared or if I suddenly needed to increase exertion for food. I find it plausible that exercise has costs that are being overlooked. I'm always impressed by the longevity of academic-types I find in wikipedia, who I presume don't run marathons often. NFL players have extremely low lifespans. Marathon runners tend to have higher rates of heart damage.