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How would respiration be surprising to anyone with a high school level education?

> This analysis makes it clear why exercise is so powerful in the weight loss equation.

There are many reasons to exercise, but it's quite clear weight loss isn't one of them. I mean, you need to exercise to get your abs to pop, but not being a lard-ass is totally about avoiding excess calorie intake and exercise really doesn't enter into it. People don't realize what a trivial amount of calories working out burns.

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>People don't realize what a trivial amount of calories working out burns.

I think it's more that people don't realize how stunningly high calorie counts for "bad" food can be. Like a cookie might take 20 minutes of exercise to burn off the calories, but that's more about the cookie than about the exercise.

Even burning through a single Granny Smith Apple takes ten minutes. Half a cup of dried cherries, dried pears, or raisins, would take over 20-25 minutes. All of these are pretty natural.

Undeniably there are artificial foods with insanely high calorific levels for either their volume or weight. But all foods are inherently hard to burn off via exercise. Some are just worse than others.

Partially because those foods aren't really 'natural'. They are the result of 1000's of years of human selection for sugar and carbos. We've genetically engineered nearly every fruit and grain, the hard way, by crosspollination and grafting and selection through the centuries. We've made them very calorie-laden, because that helped us survive in harsher olden times.

Yes, taking a sweet fruit and removing all the liquid leaves you with something that is remarkably unhealthy by weight, despite being "natural." But that just means that eating a lot of dried fruits and nuts and such is not a great diet choice.

It's not clear to me. Exercise is a good way to burn calories. But perhaps more significantly, if you do it regularly, you will burn more calories even while at rest.

As I understand it, the amount you can increase your caloric burn rate through exercise is generally much smaller than you can decrease your caloric intake through dieting. The result being that, as some fitness communities say, weight loss is done in the kitchen.

Because the calories lost via exercise are insignificant, compatible to skipping a snack unless its very intense.

I guess "significance" is in the eye of the beholder, but skipping a snack seems significant to me.

How are you defining snack?

One problem with exercise isthat it doesn't burn many calories, and some people "reward" themselves for doing that exercise with an extra bit of cake.

It's really easy to burn an additional 500+ calories with exercise, which is very significant. Of course it's not a substitute for a proper diet, but it can be a huge factor in weight loss.

500 calories in one session? Or over a whole week? In one session it is definitely not "easy." In a whole week it is.

If you walked at 2.5 MpH and weighed 160 pounds, it would take you two and a half hours to burn your 500 calories. To me 2.5 hrs is not an "easy" workout. Somewhere between medium to hard (depending on fitness level).

A single Big Mac is almost 500 calories, two snickerdoodles are more than 500 calories on average.

> Of course it's not a substitute for a proper diet, but it can be a huge factor in weight loss.

That's just not true.

A single combo from McDonalds could set you back an entire weeks worth of exercise, literally. If you exercised for an hour a day every day, it only takes a single meal to undo most of that weight loss.

PS - Exercise is, of course, very important for overall health and a long life. Nobody is arguing otherwise. But for weight loss? Heck no. The maths simply doesn't work at all.

It depends on whether you consider intensity or duration to determine how "easy" a workout is. Sure, 2.5 hours is a lot of time to invest, but walking at 2.5 MpH hardly seems strenuous enough to qualify as exercise.

A 160 pound person could burn 500 calories in ~40 minutes jogging at a 10 minute per mile pace, and could easily offset a Big Mac in a single day's exercise (not saying that the person should use this to justify eating a Big Mac).

It is most definitely 'easy' to burn 500+ calories in one session.

One hour of squash burns 600+ calories. One hour of running burns 600 ish calories. One hour of cycling burns something like 400-500 calories.

No citations for these figures, just going off memory

Burning 500+ calories per session is definitely doable - if you are doing the right exercise in the right ways for the right duration.

> you will burn more calories even while at rest.

Not really. Probably even a bit the opposite. If you exercise hard daily the resting metabolic rate actually drops some as an adaptation to conserve calories: exercise induced hypothyroidism. Pro level cyclists have to count calories to keep their weight down and they don't eat nearly as much as you'd think.

Muscle mass preferentially burns fat, so you get a very small metabolic edge from having some extra muscle, but not much. Adipose tissue also burns a great deal of calories, believe it or not, so getting really fat is a good was to increase your metabolism. This is why when obese people start restricting calories the first 30 pounds or so pretty much melts off with not much difficulty.

Exercise for overweight people is important for the health benefits which exist even if no weight is lost. Exercise does help people lose weight. It's probably important to manage expectations - exercise alone is not as good as diet change and exercise combined.

http://www.cochrane.org/CD003817/ENDOC_exercise-for-overweig...

> The results of this review support the use of exercise as a weight loss intervention, particularly when combined with dietary change. Exercise is associated with improved cardiovascular disease risk factors even if no weight is lost.

The health benefits of exercise come from "conditioning" sessions, not watching some ill-informed calorie meter. Exercise makes you fitter and healthier by hitting progressive overload. Meaning it has to be difficult, nay unpleasant, and thus done rather infrequently to allow plenty of recovery time.

cbass.com has this stuff dialed in. One im-gonna-puke strength session a week and one difficult endurance "cardio" session makes a ton of sense to me, when you take in the literature. Much more and exercise starts to look like a net negative in many ways. Suggesting to a fatty that they jog five times a week is at best a waste of time and at worst actively harmful.

I posted a link to an internationally reputable organisation who do gold standard meta analysis.

You? My neuro-atypicality means I geniunely don't know if you're trolling and yours is a parody post, or if you actually think cbass.com - a comercial site selling get fit quick dvds and books - is a reputable cite.

One question: if they have it "dialed in" why are they selling ten different books?

Your gold standard meta-analysis is useless for the purposes of someone actually trying to lose weight. It merely takes the position that diet and exercise produce better outcomes than either alone. That tells us nothing about which has the more powerful effect.

Anybody who's actually tried, and succeeded, in losing weight and keeping it off will tell you that diet is way more important than exercise when it comes to fat loss. Exercise absolutely produces health benefits, but they are largely orthogonal to the ones produced by changing how you eat. If you can do one but not the other, then diet.

Most people with a lot of weight to lose have willpower problems, that's why they have a lot of weight in the first place. Not all, but most. These people are better served conserving their willpower and taking more effective courses of action than the one they can't take. (both diet and exercise)

Did you read the paper? You start by saying it's useless; then you repeat what it says.

If you're interested in this point, you should read Gary Taubes' book Why We Get Fat.

http://www.amazon.com/Why-We-Get-Fat-About/dp/0307474259

The third chapter is all about why exercise isn't a good way to lose weight. It is generally a fantastic book.

The resting metabolic rate thing is a myth. In fact if you google metabolism myths that's one of the biggest one. Just going off memory a pound of muscle burns like 10 calories per day while a pounch of fat burns like 5. So replacing a pound of fat with a pound of muscle nets you 5 calories burned per day. Not exactly amazing considering you need to burn about 3,500 calories to lose a pound of fat.

Also consider... I'm a 33 year old 215lb man. An hour at the gym lifting weights is about 340 calories, or approximately the amount of calories you get by drinking a couple glasses of soda at lunch and dinner. You need 10 trips to the gym or 10 days without soda. Assuming you go to the gym 3 days per week, that's 3 weeks of exercising compared to 1.5 weeks of drinking water instead of soda.

Um, don't you mean nets you 5 calories a day, not 15?

Yep, you're right. I'll fix it.

A 45 minute full HIIT workout should burn about ~1000 calories; not exactly trivial.

You'd need to be a pretty good athlete to burn 1000 calories in 45 minutes straight.

You have to be in pretty fucking great shape to last 45 minutes of HIIT.

True, but it's pretty easy to do 600 calories of exercise in 45 mins. Which is still a hamburger or so (not the fries.)

But a lot easier (and faster) to skip the hamburger.

> But a lot easier (and faster) to skip the hamburger.

I wish I found it as easy as that.

That's absurdly high. If you can sustain that level of activity, you likely don't have the weight problem in the first place.

I'm a couch potato, I can burn about 300 cals per half-hour (according to the stationary bike machine or elliptical). In my better days, that was up to 350 cals per half-hour, I was quite fit but not athletic.

This is of course trivially verifiable. To burn 1000 calories in 45 minutes if your body is an average 25% efficient requires around 385W of continous power output. The majority of women will struggle to output this for a mere minute while most men won't last 5.

So no, your 45 minutes of HIIT isn't burning 1000 calories, and if calories are your goal, you would obviously not be doing HIIT in the first place (what's the point in getting nauseous when you can just produce these steady watts).

(That said, I still heavily disagree with the grandparent; exercise is as much part of a diet as is calories in / out. If you can do 150W for a grand total of 5 hours every week, that totals 2500kcal or more than an extra days worth. For many people, time spent exercising is also time spent not sitting idly in front of a TV and eating.)

Genuinely curious where you get the 25% efficient number. Is that an established figure for cyclists or something?

It would be interesting to know the particulars, but in general you hook up a cyclist up to a dynamometer and a ventilator, and you measure both the amount of work done and the amount of CO2 produced. I say "cyclist" because they're the easiest ones to hook up to a dynamometer.

http://www.ncbi.nlm.nih.gov/pubmed/12471319 quotes gross mechanical efficiency at 24.5 +/- 0.7% for world class cyclists.

More importantly, however, http://www.ncbi.nlm.nih.gov/pubmed/15241718 finds no differences in efficiency between world-class and recreational cyclists.

In any case, the "cycling" bit is somewhat of a smoke-screen; it just so happens that it's most easily measured and objective data has long been available through power meters. There is no free-lunch, regardless of the particulars of any sport.

(I should however probably clarify that the power numbers quoted above are mechanical power as measured during cycling, which is pretty much the only sport that even has ways of measuring power reliably)

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