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Exercise and Weight Loss: Shouldn’t somebody see if there’s a relationship?

The first two or three paragraphs of this post aren’t going to sound like they have much to do with weight loss, but bear with me.

In October, I ran in a 3K (1.86-mile) “fun run” at my workplace, and was shocked to have to struggle to attain 8-minute miles. This is about a minute per mile slower than the last time I did the run, a few years ago, and that previous performance was itself much worse than a run a few years earlier. I no longer attempt to play competitive sports or to maintain a very high level of fitness, but this dismal performance convinced me that my modest level of exercise — a 20- to 40-mile bike ride or a 4-mile jog each weekend, a couple of one-hour medium-intensity exercise sessions during the week, and an occasional unusual effort (such as a 100-mile bike ride) — was not enough to keep my body at a level of fitness that I consider acceptable.

So after that run in October, I set some running goals: 200 meters in 31 seconds, 400m meters in der 64 seconds, and a mile in 6 minutes. (These are not athlete goals, but they are decent middle-aged-guy-with-a-bad-knee goals, and I make no apology for them). Around the end of October, I started going to the track 5 or 6 days per week, for an hour per workout. I started with the 200m goal. I alternated high-intensity workouts with lower-intensity workouts. All workouts start with 20 minutes of warmup, gradually building in intensity: skips, side-skips, butt-kicks, , a couple of active (non-stationary) stretching exercises, leg swings, high-knee running, backward shuffle, backward run, “karaokas” (a sort of sideways footwork drill), straight-leg bounds, and finally six or seven “accelerations”, accelerating from stationary to high speed over a distance of about 30 meters. After the 20-minute warmup, I do the heart of the program, which takes about 30 minutes. (The final ten minutes, I do “core” work such as crunches, and some stretching). A high-intensity workout might include running up stadium sections (about 12 seconds at very close to maximum effort, followed by a 20- to 30-second break, then repeat, multiple times), or all-out sprints of 60, 100, or 120 meters…or a variety of other exercises at close to maximum effort. Every week or so, I would do an all-out 200m to gauge my progress. My time dropped by about a second per week, and within about 6 weeks I had run my sub-31 and shifted my workouts to focus on the 400m goal (which I am still between 1 and 2 seconds from attaining, almost three months later, but that’s a different story).

So where does weight loss come in? I was shaving off pounds at about the same rate that I shaved off seconds in the 200m: I dropped from around 206 – 208 pounds at the end of October to under 200 in early December, and contined to lose weight more slowly after that, to my current weight of about 193-195. About twelve pounds of weight loss in as many weeks.

A few more relevant facts: (1) I’m quite tall, almost 6’4”, so my heavy-sounding 207 lb starting weight put me barely outside of the “normal” range by “body mass index” (BMI). My current weight of around 194 lbs is in the upper part of the “normal” range, although I’m still between 5 and 10 pounds heavier than I was in my early 30s, when I was playing a lot of competitive sports and was in pretty good shape. (2) During all of the time listed above, I have made no effort to control my eating. I still indulge my sweet tooth, often eating dessert at both lunch and dinner, and I pretty much eat what I want, when I want.

In short, there is no question in my mind that my weight loss is due to my exercise program, not to dietary changes. (And I guess I should mention that I had similar experiences back when I styled myself an athlete, putting on five pounds or so during the off-season and losing it once I started high-intensity work again). And yet, at around the time I was starting this program, articles were appearing like this
based on studies like this and this
that say that people, or at least most people, don’t lose weight from exercising alone, they have to do some sort of dietary control too; otherwise, the studies say, people increase their caloric intake to compensate for their exercise. So the studies say one thing, but my experience says another. What gives? Am I really unusual, responding to exercise in a way that differs from other people?

Well, I recently looked at the studies (or at least the abstracts for the studies) that claim that exercise doesn’t lead to weight loss, and noticed that the exercise intensity is quite low. For instance, one of the studies had people exercise for an hour at “55% of aerobic capacity”; a different study had people exercise at “70% of maximum heart rate.” These are about the same. Working out at this level, you definitely feel like you’re exercising, but it’s not a painful level of exertion. This is just a bit higher than the level at which I’m working during the second half of my warmup. So, what they are calling “exercise” for purposes of these studies is the level of exertion that I attain before I start exercising!

The theory that the weight loss/exercise researchers seem to be following is that, since a pretty low level of exertion maximizes the rate of fat-burning — at higher intensity your body switches to using glycogen — this low level must be optimal: if you don’t see weight loss from moderate exercise, you won’t see it from intense exercise. Well, that’s a reasonable theory, but it’s not necessarily right, and indeed from my experience I would have predicted that higher intensity exercise would be better, even though it doesn’t burn as much fat. As to how this could be, I don’t know. Maybe high-intensity exercise doesn’t increase one’s appetite as much as low-intensity exercise does, or perhaps it causes a long-term increase in metabolic rate that lower-intensity exercise doesn’t cause. I don’t have a physiological explanation, only the empirical observation that I, at least, lose weight (and quickly!) when I start doing high-intensity exercise, even if (even though) I make no effort to control my diet.

Doesn’t it seem like someone should study the effect of exercise above warmup intensity? At the very least, they should say “exercise at low or medium intensity doesn’t lead to weight loss,” rather than assuming, based on no data, that that is true of high-intensity exercise as well.


  1. JDM says:

    I have observed similar effects in myself. I try to follow an exercise program of high intensity interval training on a treadmill for a couple of days and then every third or fourth day do a full body weight training program. When I stick to this program, I invariably loose weight over the course of a week. If I skip two or three days a week, my weight is stable, and if I miss more than three days I start gaining weight, more or less independent of what I eat. I agree that the results of these studies are probably due to the exercise being low intensity.

  2. Blake R says:

    I agree the studies you mention are too quick to assume their results generalize to all types of exercise. The book Body by Science by Doug McGruff and John Little, which centers around the difference between high and moderate intensity exercise, argues the former is substantially better. The authors lay out the metabolic processes activated by each, concluding that high intensity, low volume exercise has the same fitness benefits, but with fewer detrimental long-term effects and more weight-loss.

    I'm still evaluating the book's argument and trying to take it with a grain of salt, but if the authors are correct, burning glycogen is the source of most of these benefits. Even though your cells aren't as likely to burn fat while you are exercising, glycogen release increases insulin sensitivity, making your body more willing to shed fat later on. High levels of moderate exercise that never engage fast-twitch muscles are as likely to consume the unused muscle for fuel as fat. The build-up of lactic acid from anaerobic exercise has to be processed by the aerobic system, so your body continues to burn calories in recovery. With glycogen stores in the muscles depleted and insulin sensitivity increased, consumed calories are more likely to go back to muscle instead of fat.

    Multiple studies done at McMaster University seem to indicate that fitness benefits of 10 minutes a week of high intensity exercise are equivalent to four to six hours of moderate intensity. McGruff and Little additionally argue that a long recovery is as important as high intensity, so they advise a single workout a week, if that.

  3. Will Griscom says:

    I agree that this hypothesis should be tested — given my own (equally anecdotal) experience training for distance running, heavy levels of exercise actually decreased my subsequent hunger, rather than increasing it in the way that these studies would predict. It also seems quite likely that significant weight loss from heavy exercise could be due to metabolic changes that cause the body to store less fat, rather than the simple additive effect of 'burning calories.'

    That said, I'm not a weight loss researcher and there may be more information out there that I don't know about.

  4. Nameless says:

    Your second link says explicitly that people in that program lost an average of 3.3 kg over 12 weeks. That's actually quite respectable: 500 kcal 5 times a week for 12 weeks corresponds to 3.9 kg of fat burned. So, only a fraction of weight lost through exercise was recovered through increased caloric intake.

    The fact that some people fail to lose as much as others can be explained too. If you have underdeveloped muscles (as many sedentary people who never seriously exercised do), even moderate exercise, at 70% max heart rate, will help build them. An average adult quadriceps weighs 2 to 3 kg (times two). You might gain 1 kg after three months of exercise just in that muscle alone. Most types of aerobic exercise would also build hamstrings and glutes.

    I would theorize that much of the "anomalous" weight gain in such a study comes during the first weeks, and, beyond 3 months, everyone starts to lose weight at the same rate.

  5. Ian Fellows says:

    First off, the BMI cut offs are not really meaningful in any sense of mortality or morbidity. As is often the case researchers started using them as convenient dichotomization in their papers, and the WHO picked them up (with the appropriate caveats). They eventually turned into hard lines because… hey if they are good enough for the WHO…

    The BMI its self is really only meant to be applied to populations, not as measure of individual health. What I would really like to see is research into what is the best measure of obesity as it relates to mortality/morbidity.

    Regarding your particular experience, I try not to read to much into a single data point. I, for instance, exercised heavily and gained muscle, but lost no fat. When I switched to a low carb diet and stopped exercising the fat went away.

    The big picture is that there is no proven way to lower someone's weight that is effective in the 3-5 year time frame (other than surgery). Exercise, low-carb, low-fat, calorie restriction, they all fail. We need more basic research into obesity, because as scientist, we have no idea what we are talking about.

  6. A says:

    So you didn't tell us, but in the end, do you think you could run faster /because/ you were lighter?

  7. Phil says:

    Ian, I don't really care much about BMI, I just wanted to give people an impression of where I was when I started my program. A lot of people probably have trouble picturing what "6'3.5'', 207 pounds" means: is this guy lean or fat or typical or what.

    Ian, I have to quarrel with your statement that "there is no proven way to lower someone's weight that is effective in the 3-5 year time frame." I consider it "proven" that I controlled my weight effectively with high-intensity exercise for almost my entire adult life. During periods (injury, off-season) where I didn't do such exercise, I gained weight; upon resuming, I would lose it again. Once I stopped that high-intensity work, several years ago, I gained weight. Now I have resumed high-intensity exercise, and I have quickly lost it again. In other words, this program works FOR ME.

    Anecdotally, it appears that JDM has the same experience, and perhaps Will (although I can't tell if, when he says "heavy" exercise, he is referring to exercise near max intensity). Will and Blake and Nameless all have positive things to say about this, too, although without any explicit weight-loss claims.

    Now, it is entirely possible that most people are not willing to work out at very high intensity several times per week — it is really painful, though also satisfying in a way. Psychologically, most people will find it easier to spend an hour slogging away at low or medium intensity than to spend 20 minutes at low/medium and then thirty really putting the hurt on their body. I'm not claiming that, even if my hunch is correct, promoting high-intensity exercise will cause some sort of public health or fitness revolution. All I'm saying is that high-intensity exercise leads to weight loss in me personally, and I bet it does in other people too, so before researchers say exercise doesn't lead to weight loss they should check it and see.

    A, you ask if I'm faster _because_ I'm lighter. I think that if you take a runner and make him carry an extra twelve pounds, he's going to be slower, no question about it. So, yeah, losing that weight has gotta help. But I'm quite certain that losing weight is not the _main_ cause of the performance improvement: I've definitely added leg muscle and aerobic capacity, and my anaerobic endurance has improved a huge amount (although not quite enough to get under 64s in the 400m…that's really my weakness, I can hit the required speed no problem, but I can only maintain it for about 300 or 350 meters).

    There's a decathlete here — national class but not quite world class — who has helped me with my training program. He mentioned recently that (1) he has put on weight recently (muscle), so he's now as heavy as he's been in a while, and (2) he's sprinting faster than ever before. You can't be a fast sprinter if you're fat, but you don't have to lose weight to gain speed.

    For what it's worth, I'm happy to have lost the weight — I think I look a little better, and although I'm less vain than average I am not completely indifferent — but weight loss isn't my motivation, which is one reason I make no effort to control my diet. If I can hit my target times, I don't care about my weight.

  8. FH says:

    For those interested you can see what kind of quantile a 7 or 8 min mile pace in a 5k corresponds to by age/sex in a fairly popular Chicago area race here. And the workout you propose seems pretty intense compared to these. Are you resting enough?

  9. Ian Fellows says:


    I meant proven scientifically in a clinical trial.

  10. yu says:

    It is well known (at least to me) that low to moderate exercise alone won't help reduce weight. The exercise guideline and obesity guideline has also said that the effect of weight loss by exercise is "moderate" unless it is vigorous exercise.

    In this regard, there is no confliction between your own experience and the existing literature.

    The purpose of those studies is to explicitly tell the people that most exercise programs won't work for weight loss. This conclusion has been known to insiders for a long time.

  11. Phil says:

    FH, I used to play sprint-oriented sports, so that's what I used to train for, and that's what I'm working on now. That Hal Higdon site is geared towards much longer distances. Sprinters work at much higher intensity, but much much shorter mileage. I'm following a program that was designed for me by a decathlete who is also a personal trainer, so I'm reasonably sure it's a good program; it's also more or less in line with training programs you find online for the 400m (like this or this or this). That said, I am 44 years old and it's possible that both I and my trainer have underestimated age-related decline. But basically, although it's hard to know for sure, I think I am getting enough rest.

  12. Phil says:

    Ian and Yu, if what you are saying is that nobody has conducted a clinical trial to see if high-intensity exercise leads to weight loss, then I agree, and that is pretty much the whole point of my post! Somebody should do a trial to see if high-intensity exercise leads to weight loss.

  13. Nameless says:

    Phil, once again, I think that, if you conduct an experiment like that, results will be dependent on whether people have pre-existing developed muscles or not. My personal anecdotal experience is that, when I started serious high intensity weight training, I gained 15 pounds (went from 145 to 160) in the space of about three months. Muscle growth was clearly outpacing fat loss (if there was any).

    But then, if you take an out-of-shape former bodybuilder, or a person like you who apparently were playing competitive sports and who still runs 4-mile runs on weekends, he already has muscles, they are just out of shape. For him, both high-intensity exercise and low-intensity exercise are likely to produce weight loss.

  14. Megan Pledger says:

    Most of the weight loss stuff is for people who are seriously over weight and little previous excercise experience. They are not going to be able to work out at high intensity because they are too succeptible to injury – muscles adapts to excercise relatively quickly but the connective tissues take much longer say 3-6 months.

    My theory on excercise is that you should do it at such an intensity that you can see yourself doing it next week, next month and next year. What's the point if once you stop, you pile on the pounds.

  15. William O. B'Li says:

    Someone coming at this from the other side:

  16. Phil says:

    Nameless, I agree that a participant in an exercise program will gain some muscle while losing fat, so even if the weight only drops a little, they might be accomplishing a lot as far as fitness.

    Megan, I agree that people who are seriously overweight might be incapable of, or unwise to attempt, running 200 meter sprints at maximum effort.

    But both of those miss my main point, which I presumably didn't make clearly in my post: there are lots of news articles and journal publications out there that claim that exercise doesn't promote, or doesn't lead to, weight loss. I believe those articles are false, I think that for some people (including me) _high-intensity_ exercise does lead to weight loss. I wish someone would study that.

    William, if you're going to put that much work into your middle initial and last name, I think you could be more creative with your first name, too!

    That link is interesting. It mostly has advice that we've all seen before (avoid refined sugar, eat whole grains and vegetables, yada yada), but then it says "In general, exercise isn't necessarily helpful for fat loss. However, there is one type of exercise that clearly is: high-intensity intermittent training (HIIT). …The key is to achieve maximal exertion for several brief periods, separated by rest. This type of exercise is not about burning calories through exertion: it's about increasing hormone sensitivity using an intense, brief stressor (hormesis). Even a ridiculously short period of time spent training HIIT each week can result in significant fat loss, despite no change in diet or calorie intake (13)."

    That (13) is a reference to a paper in the International Journal of Obesity entitled "The effects of high-intensity intermittent exercise training on fat loss and fasting insulin levels of young women," which concludes that "HIIE three times per week for 15 weeks compared to the same frequency of SSE exercise was associated with significant reductions in total body fat, subcutaneous leg and trunk fat, and insulin resistance in young women."

    So, I guess someone _has_ done the study I've been asking for (at least one small study, but maybe there are more). And it looks like this study backs up my "theory." That's great.

    Unfortunately — oooh, this burns me up — the "significant" reduction in total body fat refers to "statistical significance" rather than actual significance. The abstract, which is all I can read online, doesn't give any information on the amount of fat loss. What is it about p-values and t-tests that people find so compelling? Is it just that they sound "scientific"? Grrrr.

  17. dan says:

    From the Int'l Journal of Obesity paper:

    "There was significant FM [fat mass] loss (P

  18. JDM says:

    Here's some data from my exercise program.
    I'm 5'8, 46. Three years ago we visited
    Lord Howe's Island in the Tasman sea. I hiked up a small but steep volcano remnant and was exhausted by the effort. Several people considerably older than me did much better. I returned to Chicago determined to get into better shape. I started the interval training program mentioned in the first comment (about 10 hard sprints on a steeply inclined treadmill for around 35 seconds each interspersed with walking, five or six days a week). I also lifted weights but think that all the weight loss is from the interval training – the weight lifting increased my weight if anything. My diet was unchanged. pmwt means PM weight. % "fat" is from a Tanata scale.

    "date" "pmwt" "fat"
    20070207 185.8 25
    20070208 184.2 25.9
    20070209 184.2 26.7
    20070210 184.8 28
    20070211 185 26.6
    20070212 184.6 24.7
    20070214 183.6 25.4
    20070215 183.4 24.9
    20070216 184 25.6
    20070217 184.2 24.9
    20070218 184.2 25.5
    20070219 185.2 26.8
    20070220 184.8 24.9
    20070221 182.6 26.2
    20070222 181.8 26
    20070223 181.4 25.8
    20070224 181.6 25.4
    20070225 181.6 24.3
    20070226 180 23.2
    20070227 178.8 23.6
    20070228 178.4 23.7
    20070301 179.8 23.4
    20070302 179.8 23.3
    20070303 178.8 24
    20070304 181.6 24.4
    20070305 181 22.6
    20070306 180.2 22.6
    20070307 178.4 22.4
    20070308 177.6 23
    20070309 178.2 23.1
    20070310 178.4 24.2
    20070311 179.6 22.8
    20070312 178.6 22
    20070313 181.2 21.1
    20070314 179.6 22.2
    20070315 178.6 22.2
    20070316 177.6 23.5
    20070317 176.6 22.6
    20070318 178 22.8
    20070319 177.2 20.7
    20070320 174 21
    20070321 173.8 21.4
    20070322 173.2 20.7
    20070323 174.2 21.5
    20070324 173 20.9
    20070325 173.4 20.8
    20070326 173 18.8
    20070327 172.2 19.4
    20070328 172.6 20.7
    20070329 172.2 20.1
    20070330 171.4 20.4
    20070331 171.2 20
    20070401 173.4 20.7
    20070402 171.4 18.6
    20070403 171.4 19.5
    20070404 172.0 19.5
    20070405 170.6 20.3
    20070406 170.8 20.4
    20070407 169 20.0
    20070408 170.2 19.7
    20070409 170.4 19.3
    20070410 170.6 18.8
    20070411 169.4 19.4
    20070412 168.6 19.1
    20070413 168.8 18.4
    20070414 167.8 20.3
    20070415 168.6 18.8
    20070416 168.2 18.5
    20070417 167.2 18.7
    20070418 168 19.4
    20070419 168.2 18.1
    20070420 166.8 17.4
    20070421 169.2 17.7
    20070422 168.8 18.3
    20070423 170.6 17.1
    20070424 170 18.6
    20070425 168.6 18.9
    20070426 169 18.6
    20070427 169 19.5
    20070428 170 19.8
    20070429 169 18.9
    20070430 168 18
    20070501 168.4 17
    20070502 167.8 16.9
    20070503 167.4 16.7
    20070504 166.6 18.3
    20070505 168.8 19.3
    20070506 169.4 19.1
    20070507 167.8 17.4
    20070508 167.4 17.5
    20070509 165.2 17.3

  19. jonathan says:

    Vast topic, marred by too many, too small, oddly designed studies.

    My experience agrees. I trained for a number of years for sprinting, which means repeated high intensity intervals. A typical workout would be repeated 6-3-2 (600 meter-300, etc.) or 3-2-1 or 2-0-2 (run one, jog one), etc. At that level, it was hard to maintain weight without eating a lot. By that level, I specifically mean what I think you're also saying, that level = intensity plus duration. I mistrust the high intensity studies because they don't last long, don't involve many people and I'm betting the participants were managing their intake. So yes they show a benefit to intensity but they don't scale well to the real world.

    Not many people can or want to exercise at a high level. The people who do this are self-selecting and studying them is not easily extended.

    I'm now older and have moderated my workouts because age increase injury – for me, to tendons. I observe that moderate exercise is relatively easy to couple with diet. Moderate exercise with weights can hold or even increase weight. It is very easy to gain weight with moderate exercise because a single latte is more than your net increased calorie expenditure.

    But as you note, what is moderate exercise? For me, moderate exercise – in my 50's – is still several levels above what most people treat as hard. Hard aerobic work for me is a heart rate in the high 160's into the 170's for an extended period. This exceeds my calculated maximum, which shows the limits of that idea. Below 150, I feel like I'm on vacation unless I'm pushing a fairly good sized hill (meaning I'm getting anaerobic, of course).

    As to numbers, I'm 5'8" and now weigh somewhere under but close to 170. I have a little fat on me but the amount is equivalent to when I wasn't weight training and weighed 155. Losing the extra 5 pounds to appear really lean and the extra 10 to be totally lean isn't worth it because I wouldn't maintain the diet needed (and the exercise level required would cause injury).

    My reading of the confusing research and my own observations are that moderate exercise is much more effective combined with intense work that stretches your capacities. This conforms to ancient training logic.

  20. jeremy says:

    Weight is not as important as the percentage of muscle to fat ratio. Marathon and long distance runners are thin but sprinters are lean with more muscle.

    The truth is for long term weight loss I am convinced that shorter workouts with gradual and increasing intensity are better than longer workouts of moderate to low intensity.

  21. Kiers says:

    Interesting disussion. But, Looking at all this with a "calm" "detached" eye of a poor athlete:
    –you re-gain the lost weight once the high intensity exercise ends.

    –you are more likely to stop exercise the more painful or will power laden it is.

    in that sense, the studies aren't too far off.
    i find it is better to do the 70% intensity for 40 minutes if all you are interested in is health and life. not all of us are "jocks". i wouldn't stand for the lactic burn and near heart attack conditions most jocks take pride in. however, judging from all the self-preening and benchmarking in the first two paragraphs (which ALL good athletes fall prey to, especially in the US culture [where marketing campaigns started the "running craze" in the 70's] ), this advice will not go over well.

    PS. Ever wonder what central park looked like in the 60s? without the "joggers"? I do! I think it was a "saner" place:)

  22. Andrew Gelman says:

    Kiers: In defense of Phil here, let me assure you that, yes, he enjoys the feeling of pushing himself. It's not preening, it's just how he is!

  23. danthelawyer says:

    I think there's a growing body of evidence that infrequent HIIT is a more efficient, and certainly much more efficient, way to achieve both fitness and weight loss than the standard approach of exercising often at a moderate intensity.

    One interesting resource for both diet and exercise information is Mark's Daily Apple. If you can get past the "paleo" framework, it's a pretty science-based site.

  24. Phil says:

    If I were talking about working on a FIFTYfour-second 400m, I'd consider pleading guilty to "self-preening", whatever that is. But when I admit to not being able to run 400 meters in SIXTYfour seconds, after working hard for months, I just don't see how anyone could accuse me of doing anything like bragging!

    For what it's worth, when I started writing the post, I initially had almost nothing about the workout, I just said "high-intensity exercise." But what does "high-intensity" mean? "High" relative to what? So I felt like I had to give some quantitative information, which prompted me to describe just the high-intensity part of one of my workouts, so people understand what I'm talking about and how it differs from the exercise programs featured in those studies I'm talking about. But then it sounded like my entire workout consisted of just a handful of sprints, which is misleading (and which would be potentially harmful if a reader tried to duplicate it). So I added the stuff about the warmup. Yeah, in the end it was more detail than I needed, but I didn't want to take the time to go back and rewrite it; it's often easier and faster to just leave what you've written, and that was the case here.

    Finally, as I've said earlier, I'm not claiming high-intensity exercise is going to be the solution to peoples' weight-loss issues. Hell, there are people in my building who take the elevator instead of walking up one or two flights of stairs, they're obviously not going to be doing all-out 100m sprints! All I'm asking is that people stop saying exercise doesn't lead to weight loss.

  25. Fitness goes against a lot of folks' normal mindset which is to be lazy. I have been guilty of it myself sometimes. But even if they do exercise, they can't give up their eating habits. Pizza, burgers, and the like, and then do a few sit ups and wonder why they still can't lose weight. And then purchase magic pills thinking it will help them.

    We need more recess. Even adults.

  26. Janet says:

    Yes, it's way contrary to public opinion which is that it's best to spend hours slogging away, but it's not news to the evidence-based fitness community.

    Here is some documentation:

    There are more citations available than what he gives in this blog entry.

  27. Glen Raphael says:

    All diets and all exercise programs "work" in the short term. And most fail in the long term for most people. Nobody is claiming that appetite or metabolism adjusts *immediately* – that you can't see a temporary improvement. It takes a while to adjust. Months. The relationship is that if you exercise (a lot or a little) or diet (a lot or a little), you initially do lose weight. Then gradually over time you find it harder to keep doing whatever you're doing and get less benefit from it. The rate of improvement slows, and eventually there is – on average – backsliding. Which is why you tend to gain the weight back when not actively training.

    If people could force themselves to maintain a caloric imbalance indefinitely they could theoretically lose weight indefinitely, but they can't. The body is remarkably good at adjusting your hunger and your metabolism to the circumstance you find yourself in. You can push it, but it will push back. One of the ways it pushes back is by making you less prone to *keep doing* whatever program is "working" for you. When you stop – and then gain all the weight back – you'll honestly believe that you *chose* to stop on your own and could have chosen otherwise. But the fact that you *didn't* keep it up – and gained all the weight back – is part of the data set that leads to the conclusion that exercise "doesn't work".

    In short, three months is nothing.

  28. FYI, here is what someone who makes a living with successful conditioning and fat loss had to say:

  29. Bill says:

    The real secret to weight loss is a combination of specific practices that need to be utilized in a consistent long term manner. This includes not only a systematic and quantized eating schedule but also that of an effective exercise regiment. This is the hard part for many people who are not "exercise minded". Its hard to get into the habit at the beginning but after a while it becomes second nature. Thanks for the discussion.