The entire point of the article was that working out hard and short a couple times a week doesn't help one lose weight, and that sustained continuous activity does. The reasoning is those bursts of short activity are met with increased caloric intake, defeating the value of any exercise.

I read the article and it does not really say that. In fact, the only bit that comes close is this: Another British study, this one from the University of Exeter, found that kids who regularly move in short bursts — running to catch a ball, racing up and down stairs to collect toys — are just as healthy as kids who participate in sports that require vigorous, sustained exercise.

I would agree with the general idea that daily walking at a relaxed pace is better than "jogging".

I think proper intense 10-20 minute workouts are so outside of the field of view of people who read and write articles like these they don't understand them. Doing a few sets of no-rest olympic lifts and then five minutes of double-unders with a jump rope does not boost your appetite much. It will make you a bit nauseous. It is not at all like going on a 15 mile bike ride or swimming a mile, which leaves you ravenous 30 minutes after.

Thats not the only part. Near the beginning about 4 groups of women, and the ones who exercized a lot did not lose a significant amount of weight over those who did not exercise beyond normal. The heavy work out group did however report eating more calories. Then there are 2 or 3 pages about low intensity workouts being good because they stimulate calorie burn without stimulating hunger (with a tangent on brown fat in rats).

In fact there are several examples in the article about compensatory eating, such as the women who would get muffins after jogging, canceling any extra calorie burn.

The study referenced in the beginning (with the 4 groups of women) did not sufficiently control diet. OP: <i> All the women were asked not to change their dietary habits... </i> They were asked, but did the women comply? Not likely, due to the compensation problem.

Bottom line: Regulating exercise without regulating diet is not likely to produce results. I don't think this is news.

It has been shown that one's metabolic rate has a certain momentum; it naturally seeks an equilibrium that is different for everybody. Exercise a little more and your body will crave more food; eat a little more, and you will naturally burn off the excess. (For most people).

If one desires a physique that differs from their "natural" state, one must very carefully control BOTH exercise and nutrition. Both are usually necessary to lose fat and gain muscle. And this requires discipline. One cannot exercise regularly and then simply "watch what they eat" and expect certain results. You need to eat certain foods at certain times in certain volumes. Amazing results can be achieved.

"natural" because there is nothing natural about having close to zero food scarcity. Most people eat whatever they want, which happens to be WAY more than they need, which isn't really "natural."

Recommended reading: - _The Paleo Diet_ - Precision Nutrition, http://www.precisionnutrition.com/ - their forums are highly recommended.

It is the exercise and eating habits combo that works. Weight gain = Calories In - Calories out.

Exercising along with the judicious diet (not starving) is what works. I recently came across two books that throw light on the interesting and useful information about high intensity-low duration exercising to develop a great body:

1. Cardio Free Diet: http://tinyurl.com/cardiofreediet and 2. The Nautilus Bodybuilding book: ISBN: 0-8092-5815-3

> Weight gain = Calories In - Calories out

Not true. People and lab animals can be made to get fatter while in caloric deficit with elevated insulin levels.

This comes up in Hacker News every time a health story comes up, usually quoting a pop-sci writer. You've stated it by far the clearest with no vagueness or handwaving so hopefully you can answer this (or provide pointers to research):

In this theory where does the stored energy (i.e. the fat) come from if not from the calorie intake? How can this be done for more than a short period of time (e.g. I know you can break down muscle for energy) without breaking laws of physics?

It's better to argue "weight gain = calories in - calories out" is not the whole story than to argue that it's completely wrong - you can't eat and drink nothing for a week and just get heavier, but what you can do is more like... eat 3500 calories extra in a week without putting on a pound of fat (1lb of fat ~=3500 calories) because your body is not trying to store as much as it can as fat, or eat -3500 calories in a week and end up slowing down your metabolism and moving less and destructing other bodily parts so you turn it into a calorie surfeit and do put on a pound of fat.

This comes up in Hacker News every time a health story comes up, usually quoting a pop-sci writer

Bit of an ad-hom on pop-sci writers there, eh?

> you can break down muscle for energy

Yes. Lean body mass can atrophy from starvation while fat deposits are growing.

The point is more that the equation as stated is a useless way to think about fat loss. Hormones drive the lean vs. fat configuration of your body, not calorie counting. Cut out someone's pancreas and they'll waste away no matter what they eat. Inject testosterone or growth hormone and they will get leaner and more muscular, all else held constant. Inject insulin and they'll get fatter.

Exercise affects your body composition more effectively when you focus on how it changes your hormone profile rather than count calories burned. High resistance major muscle group exercises boost growth hormone and testosterone and increase insulin resistance. Long distance training actually reduces testosterone levels.