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Why you shouldn't exercise to lose weight

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Re: Why you shouldn't exercise to lose weight

#121

Earlier quoted context omitted.

The whole point of the article is that the traditional "calories in/calories out" model is wrong. "Based on the research, Pontzer has proposed a new model that upends the the old "calories in, calories out" approach to exercise... He calls this the "constrained model" of energy expenditure, which shows that the effect of more physical activity on the human body is not linear."

The conclusion is: "10) So what actually works for weight loss? At the individual level, some very good research on what works for weight loss comes from the National Weight Control Registry, a study that has parsed the traits, habits, and behaviors of adults who have lost at least 30 pounds and kept it off for a minimum of one year. They currently have more than 10,000 members enrolled in the study, and these folks…

The theory says that as you do additional exercise, you get diminishing returns in terms of the number of calories you burn. As your exercise level increases, you have to do ever more exercise to burn the same number of calories, because the body has various compensatory mechanisms designed to avoid weight loss.

The traditional model proposes a much simpler linear relationship: do an additional unit of exercise and you will burn X more calories, forever. He says that is incorrect and you actually get diminishing returns, where additional units of exercise burn ever fewer calories rather than just a constant.

Re: Why you shouldn't exercise to lose weight

#122

Earlier quoted context omitted.

It's literally just calories in vs. calories out. If 400 calories/day meets your weight loss goals, all you have to do is make sure that the calories you expend + the calories you no longer intake = 400. The ratio of those two factors completely varies from person to person on what their motivation levels are going to be, but as long as it works for you it will result in the same amount of weight loss as any other ra…

The whole point of the article is that the traditional "calories in/calories out" model is wrong. "Based on the research, Pontzer has proposed a new model that upends the the old "calories in, calories out" approach to exercise... He calls this the "constrained model" of energy expenditure, which shows that the effect of more physical activity on the human body is not linear."

> The whole point of the article is that the traditional "calories in/calories out" model is wrong.

I think what they mean by this is that the "calories out" portion is what is mostly wrong (or at least, misunderstood ), not that "calories in" are probably the most significant factor when it comes to fat loss. They don't seem to dispute this.

Re: Why you shouldn't exercise to lose weight

#123
>The spinning instructor was echoing a message we've been getting for years: As long as you get on that bike or treadmill, you can keep indulging — and still lose weight

Who is saying this? Anyone who has spent an hour educating themselves on the subject knows that it's all about calories in v calories out. That can be accomplished via the gym and the kitchen, or the kitchen alone.

Exercise provides additional benefits; higher caloric deficit assuming the same diet, muscle tone (appearance and burns more calories when you're doing nothing), and general cardiovascular health.

Re: Why you shouldn't exercise to lose weight

#124
post #102
post #47

Earlier quoted context omitted.

Humans are far less than 100% efficient. Aerobic weightlifting is one of the highest energy burns per minute of any exercise type.

What is aerobic weightlifting? Weightlifting is an anaerobic activity.

Power lifting can quickly become anaerobic, when you run out of oxygen. But, weightlifting is used for more than just peak power. Many activity's benefit from pure strength, but most people are trying to improve both power and endurance.

Longer cool down periods (3-5 min) helps build strength faster and let's each set be more anaerobic and higher weight, but short cool down periods and slightly lower weight adds endurance and strength, plus more repetition.

The other benefit of aerobic weightlifting is you can better learn to minimize anaerobic activity. Full power all the time seems great, but being dead on your feet in 30 minutes is rarely useful.

Re: Why you shouldn't exercise to lose weight

#125

FWIW, my experience disagrees with this. I was overweight, started running (starting around 9mi/wk, when I got bored and stopped I was up around 24mi/wk), and started losing weight quickly, lost a ton of it over a year, after which I was at a very good weight for me. Now, as the piece touches on, that exercise did change my eating, but the outcome of that isn't clear to me -- I stopped eating/snacking for a few hours…

It's literally just calories in vs. calories out. If 400 calories/day meets your weight loss goals, all you have to do is make sure that the calories you expend + the calories you no longer intake = 400. The ratio of those two factors completely varies from person to person on what their motivation levels are going to be, but as long as it works for you it will result in the same amount of weight loss as any other ra…

I (despite the article) am mostly in agreement with you, but I think that calories out is a very complex subject. For example, when I calculated how many calories I was burning on my longer runs, it ended up being around 3000 calories/week. However, as I said before, my intake went up. Way up. I ate like an idiot. Donuts? Yeah. Cheeseburgers? Sometimes ordered two. Dr. Pepper? Bring the two liter! I absolutely added more than 3000 calories to my diet after I started running. And yet despite all that, I just kept dropping weight.

The human body is a very complex, non-linear thing. Discerning operating principles by looking solely at inputs and outputs is a hard problem.

Re: Why you shouldn't exercise to lose weight

#126
post #53
post #32

Earlier quoted context omitted.

Eat (drink) 4000 calories of gasoline. wont make you fat. point is: only calories you can convert into "human fat" will make you fatter. that process can not happen without certain chemicals (hormones) in your body, like insulin mentioned above. it's not as straightforward as that which was op's point.

Are your confusing nutritional calories with physics calories? When people talk about diet, of course they are talking about calories obtained from digestion, not combustion engines.

Energy is energy, a calorie is a calorie in gasoline, food or electricity. However when talking about nutrition labels, those are generally an estimate of calories potentially extracted by humans (which I think is what you mean with nutritional calories). I'm not confusing anything. But some people seem convinced that the car analogy is exactly how the human body works - you put food into your mouth and it gets "burned" by exercise or stored (calories in, calories out) and no amount of evidence or science seems to convince them otherwise.

Re: Why you shouldn't exercise to lose weight

#127

Earlier quoted context omitted.

The conclusion is: "10) So what actually works for weight loss? At the individual level, some very good research on what works for weight loss comes from the National Weight Control Registry, a study that has parsed the traits, habits, and behaviors of adults who have lost at least 30 pounds and kept it off for a minimum of one year. They currently have more than 10,000 members enrolled in the study, and these folks…

The theory says that as you do additional exercise, you get diminishing returns in terms of the number of calories you burn. As your exercise level increases, you have to do ever more exercise to burn the same number of calories, because the body has various compensatory mechanisms designed to avoid weight loss. The traditional model proposes a much simpler linear relationship: do an additional unit of exercise and y…

I understand that. My point was that I've never seen a plan where people tell you to eat as much as you want as long as you do x hours of activity per day. The only plans I've seen like that are for strong men competitors or where the Rock ate like $300 worth of food every day and worked out for six hours daily.

Re: Why you shouldn't exercise to lose weight

#128

FWIW, my experience disagrees with this. I was overweight, started running (starting around 9mi/wk, when I got bored and stopped I was up around 24mi/wk), and started losing weight quickly, lost a ton of it over a year, after which I was at a very good weight for me. Now, as the piece touches on, that exercise did change my eating, but the outcome of that isn't clear to me -- I stopped eating/snacking for a few hours…

It's just a bad title. The title should have been "Why you shouldn't exercise to lose weight without changing your diet". If you eat the same amount as you did before, assuming that was maintenance calories, you will lose weight if you begin exercising. The problem is when you're intaking 1500 more calories than necessary before you start exercising. You can't burn that off to the point of a deficit with exercise alo…

Except I didn't eat the same as before. I ate more, way, way more.

Re: Why you shouldn't exercise to lose weight

#129

I've noticed in some cases that exercise can actually stave off hunger pangs - both while doing it and afterward for a while (you want water more than food) - and in this manner it can act as an appetite suppressant. As long as you ignore the body's impulse to eat more than usual when you finally do sit down for a meal, it can very much work in your favor. There's also a phenomenon people refer to as "shrinking stoma…

I have seen exactly the opposite effect on myself. After exercise I can (and really want) to eat the world.

Re: Why you shouldn't exercise to lose weight

#130
>Surely I had earned an extra margarita.

You can stop reading right there, that's the problem. You have to both eat well and exercise to lose weight. You don't get to eat extra things just because you exercised.

Focus on two things: First, portion control. I know it's wasteful for the environment but I get the single serving versions of (healthy) things (e.g. pre-sliced cheese, single cups of greek yogurt instead of the big tub, etc) so you know exactly how much you're eating. Get a kitchen scale and some measuring cups for everything else, the odds are excellent that you're a crappy estimator. And bring your lunch to work.

Second, blocking out time in your day for exercise, even if you don't work that hard. It's important to put on your workout clothes and at least go through the motions until it's an ingrained habit (1-3 months in my case but ymmv). Once it's an ingrained habit it's much easier to keep going. I start to feel gross and unclean if I go more than three or four days without some kind of strenuous exercise.

It's a lot of work and it's very difficult, but it's not complicated. With these two things I have lost 70 pounds and kept it off for seven years.

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