51 comments

[ 2.7 ms ] story [ 97.1 ms ] thread
There's strong evidence that exercise is actually counterproductive when trying to lose weight.
Can you provide some links for that?
Not a link, but certain individuals in the pop-diet field argue exercise increases appetite and may cause you to lose self-control binge on the wrong kinds of foods. Or, they'll perform a workout that burns 200 calories and then promptly down a sports drink that puts 200 calories right back into their system.

Others state that unless you're carefully balancing your calories vs. your workout level, you can push your metabolism into "starvation mode" - for example: lets say you require 2300 calories to maintain your weight, but you want to slim down so you decide to consume 2000 instead. If you throw exercise into the mix you're burning off an extra 300-500 calories (a net of 1500-1700 calories) which may put your body's metabolism into starvation mode. Because different people's bodies response to exercise differently, actually tracking your net caloric intake is challenging and not fully understood.

And of course there's the studies that show exercising alone with no diet plans seems to have a negligible impact on weight loss.

I hope I didn't misrepresent their arguments, but that's the gist of them.

There are two things going on: exercise, and eating. You have to get control of both, however you do that. If exercise makes you eat more, you have more work to do on the eating. If you do eat more because of exercise, at least make sure the food is good for you.
Humans aren't robots. I'll skip the philosophical discussion about whether or not will power exists (as you'd clearly need it to) but the fact is that if exercise makes you lose 200 calories worth of weight, but then makes you consume 250 calories, it's not helping you lose weight.

It's helping you in a number of other different ways perhaps, I was certainly not saying someone should not exercise. It's just not an effective weight loss technique.

Also when you add up the calories burned, even vigorous exercise just isn't that much. It's FAR easier to cut calories out of your diet than to exercise them away even if you assumed exercise did not make you hungrier or affect you in any other way adverse to weight loss.

Exercise doesn't just burn calories during the period of time in which you are performing the exercise though. '200 calories' after 30 minutes of running doesn't mean that the run burned 200 calories. It means you burned 200 calories in that 30 minutes - over time, the running also builds leg muscles and encourages other physiological changes in your body that boost your base metabolic rate, allowing you to burn more calories even while sleeping.

To build that muscle, you have to feed it, so consuming more to burn more isn't necessarily out in left field as far as nutritional science goes.

Some weight lifting sources (e.g. http://stronglifts.com/) say that cardio-exercise is almost useless for losing weight. They hold that building muscles with, say, weightlifting will work much better, because you will have a higher base metabolic rate.

There should be studies about this in the literature.

Exercise causes the body want more food.

I know it happens to me - after I work really hard, I'm very very hungry after, and I end up eating too much.

You can eat as much chicken and broccoli as you want!
Someone posted an NYT article that linked to a good study.
bs. How many fat joggers do you see?

It's pretty simple - burn more fat, eat less crap.

Also, carrot is obviously good for the eyes. After all, how many rabbits wearing glasses do you see?
Might be survivor bias - if you are fat, you can't run very well, so maybe few fatties keep running.
That's like saying "If you don't know how to play the piano, few beginner pianists go on to be able to play well".

I think it's just about determination, and wether you actually care enough about achieving the goal.

Prove it by becoming a master piano player then :-)
Overweight people tend to have joint issues that make running really painful. With respect, I don't think it is nearly so simple.
How many no handed pianists do you see?

It's pretty simple - playing the piano causes limb regrowth.

Are you saying that once you're fat, it's impossible to exercise? I don't buy that.

If you're thin is it impossible to eat?

I think what he is saying is that your views are very black and white, and it's just not that simple. Maybe my definition of fat is different than yours, after working at a tech company for 5 years, but when I think fat I think 300lbs+, not 200lbs with a beer gut that can be jogged off in a few weeks. Some of these people have trouble walking to their cars without some kind of assistance, what is your solution for them? But hey, way to generalize a whole lot of people. Fat is fat, right?
Obviously the solution is to not get into that state in the first place. But granted, easier said than done for some people.

I'm talking about fat - able to exercise if you try. Not talking about morbidly obese.

I'm suggesting that the explanation "you don't see fat joggers because fat people don't jog" is as or more likely than the explanation "you don't see fat joggers because anyone who takes up jogging becomes thin so quickly that nobody sees them during the time when they are fat and jogging".

If fat people took up jogging and became thin, you would see fat joggers.

i am an overweight jogger. of course, i have lost 20 lbs since i started jogging, so we'll see how long that lasts ;)
So the issue isn't that exercise doesn't work, it's that either fat people don't take up jogging, or that exercise does make you thin.

Which was my point.

If you assume that's a causation rather than a correlation do the world a favor and don't go into science.
Alternatively, he could do himself a favor and _do_ go into science. Or however that sentence should have been formed.

Then he'd learn about the difference.

My point is, if fat people jog, they don't stay fat for long.

Perhaps I should have been clearer. But I'm lazy.

Yeah, but evidence suggests that isn't true. Studies of people trying to lose weight show that those who exercise and those who don't lose the same amount if you control for eating.

People who cut out calories and exercise lose the same as people who cut out calories and don't. People who exercise without changing eating habits don't lose weight, just like those who do nothing at all.

It's best obviously to do both though. You really don't want saggy skin falling off your body all over the place...
This has gotten a lot of upvotes in a very short time, so it must be ringing true with a lot of readers. I'd encourage some healthy skepticism.

1) It is really tempting to try to understand ourselves based on the assumed lives of our evolutionary ancestors, but the fact is we know almost nothing about their lives, and conclusions we draw from what we can guess are unlikely to be accurate.

2) There is not one citation in this entire article. This is all opinion, no matter how true it sounds.

3) He offers medical advice based solely on his personal experience. Sleep apnea may not be the same to all people.

With all that "paleo diet" rage, raw-foodians etc, I think that pop evolutionary biology is the new pop psychology.

Nutritional science is friggin' hard. Extrapolating from biological reactions has to take a huge load of variables into account and empirical studies have to monitor a huge bunch of people over a long period of time -- and all of them are lying.

Do you know of any good nutritional science resources/explanations? I wish I knew where to find a readable overview based on careful research.
There was an article on HN about the subject a while ago (http://www.nytimes.com/2007/01/28/magazine/28nutritionism.t....) that was quite interesting and modest.
That article is as much BS as the rest. Take the first line:

> Eat food. Not too much. Mostly plants.

Why should I eat "mostly plants"? He hands out a bunch of advice and never bothers to lay out a basis for his opinions.

He spent 4 books laying out the basis for his opinions, along with citations, medical research, and the like. That article is just a summary of a long body of work by Pollan.
But it's on the internet. It must be true.

Also, it has pictures, some of which are attractive females. I'm sold!

Yes and no. To be honest I think right now nobody has a god damn clue how the body regulates fat and how weight gain really works. People recommend fruits, while fructose is probably one of the worst things you can eat. I can only recommend the book "Good Calories, Bad Calories" from Gary Taubes. Basically it explains the philosophy behind low carbohydrates, no sugar and high protein & fat. Makes evolutionary sense, too. At least that's what I believe in.
Fruits are much different from high fructose corn syrup.

I think that people really over complicate things. On an abstract 'surface' level, it is a very simple feedback system. If you have an idea as to how it works, you should be able to adjust your response to the system (similar to introspecting your brain to adjust your mood).

I therefore try to use a very simple set of rules:

1.) Be hungry before you eat (actually hungry, not bored and looking for something to do...). (Corollary is 'don't snack'; how would you get hungry if you are eating potato chips all day?). I also try to ask myself 'am i hungry or did i just see a commercial for something and it gave me a craving'.

2.) Don't eat until you are full (that stretched out feeling is bad). Eat until you are not hungry (you have to eat slowly to do this).

3.) Mostly plants, lots of water, protein is good too, processed stuff is bad. Cooking for yourself is generally much healthier (if you have common sense and don't set yourself on fire).

4.) Exercise is good, but don't get any delusions of looking like an underwear model. Underwear models aren't any more natural than fat people.

> To be honest I think right now nobody has a god damn clue how the body regulates fat and how weight gain really works.

And, it's unclear that it necessarily works the same way in all people.

My opinion is that decomposition is the only permanent weight loss. Before then, there's maintenance, both successful and not which varies by both individual and circumstance.

"People recommend fruits, while fructose is probably one of the worst things you can eat." -- fructose is bad for you. Much worse than glucose. However, the amount in fruit compared to anything with HFCS is not even in the same ballpark. Also, fruit is fibrous and mostly delicious. Avoid fruit juice that gets rid of the bulk, but feel free to eat fruit freely (unless you are pursuing ketosis, obvi.)

I think all of the studies show that most people don't keep weight off, and that the slower you lose the weight the more likely you are going to keep it off. Also, running is good for the brain as well as the body.

"There is one other thing. You must exercise at least an hour every day. Walking is best."

Last month, we exhibited at our largest trade show of the year–at the MGM in Vegas. I ate like a pig for a week. The Grand Buffet. Kobe ribeye at Craftsteak. Sushi. Beer. In N Out Burgers. You name it.

When I came home, I had lost 6 pounds.

We also walked a ton that week, stood in our booth for 8 hours a day, and hauled a lot of stuff during the setup/teardown.

I think people misunderstand what it means to "exercise" (at least in terms of losing weight). You don't have to go to a gym ... just get on your feet and move.

Agreed. It's remarkable - My weight has varied between 160 pounds and 210 pounds, and almost has 100% correlation with a single factor - whether I was carpooling or walking into work. Diet, secondary exercise, type of food I'm eating - none of them seem to have anywhere near the causative impact as just simply walking 25-30 minutes into work (and back) each morning. Every morning. Every Day. For months on end.

I have friends who mock this, and talk about how much more important it is to get into their peak-heart-rate on their at-home treadmill. That they've actually used maybe a couple dozen times.

I don't have a choice - have to walk to work. And Back. 3 1/4 miles a day. Every day.

That's almost a marathon a week. :-)

Walking 3.25 mi in 25-30 minutes? That sounds a bit too fast :)

PS. Sorry I'm just in a bad mood and feel the need to be anal.

I read it to be 3.25 mi total each day and 25-30 minutes each direction making the 3.25 mi tile ~ 1 hour. That seems a reasonable pace to me.
the initial role of big brains was for sexual attractiveness. For a long time, hominid females were selecting for big brains. Big brains served the same purpose as big tails do for peacocks. I think perhaps that those females were determined to someday produce a man with the mental capacity to understand women.

While this abstract is slightly funny, I suddenly realized that I have no idea about why humans evolved big brains. Why most of the other species do not select for bigger brains, while human evolution seems to suggest that a bigger brain is a much better survival tool compared to sharp claws or protective colour? Certainly, other species would have offspring which have slightly larger/smarter brains. Why is that only a few species (humans, dolphins ...) evolved relatively large brains?

Probably random mutation that happened to turn out beneficial for us. In evolutionary sense, a larger brain doesn't seem to be of utmost importance for reproduction.
Probably random mutation that happened to turn out beneficial for us.

Yes, but isn't that just restating the theory of evolution and natural selection?

This is from a Nova science documentary (Becoming Human): some scientists believe that humans evolved larger brains in response to a rapidly changing ecosystem. They've found evidence of a ginormous lake appearing and disappearing many times repeatedly over a few thousand years, in the Rift Valley, near where early hominids started evolving larger brains. The theory is that the rapid adaptability afforded by a larger brain was what selected for it.
Consult an attorney before applying any of the tips