You’ve embarked on a new weight loss diet or fitness program. You’ve read a book, become inspired, signed up for a program or health club and what’s more — it’s working. For the first week, two weeks, a month, the weight is coming off, you’re hitting the gym on a regular schedule. You even drop a size or two and garner some compliments from friends.
And then…progress stalls. You’re still eating the same foods, faithfully completing your workouts, but your weight loss stalls, perhaps the scale even goes up a few pounds. The progress you make at the gym similarly maxes out…you can’t lift any more weight, your running speed or distance maxes out…maybe even some soreness or injury sets you back a bit. You’ve hit the dreaded plateau. Sometimes it lasts a few weeks and progress resumes. But it can last months. And it saps your morale because you are not getting any more return on your invested effort. In all likelihood, you give up or cut back, your discipline withers. Your weight goes back up, maybe adding a few pounds on top of where you started, and you cut back on or cut out your exercise program. The genie is back in the bottle.
What causes plateaus? Are they inevitable endpoints in any effort to make progress? Or are they at best temporary way-posts or resting points that you can move beyond with the right approach? The school of thought that says that plateaus are unavoidable indicators of biological limits is called the Set Point theory. I think that the Set Point theory is wrong, and that there is a reliable way to push past plateaus to bring about substantial weight loss and improved fitness.
Conventional plateau busting suggestions. Before we get into the Set Point theory, let’s take a look some typical suggestions you’ll get if you google “plateau busting” or “break through plateau”:
To break through exercise plateaus:
- Increase exercise intensity
- Take a break – don’t overtrain
- Try new exercises
- Mix up your routine, change the order of exercises
- Wait out the plateau
To break through diet plateaus:
- Eat more frequently, don’t skip meals
- Eat different foods
- Drink more water
- Wait it out
Many of these are good suggestions, and they can work to jump start progress. But I suspect that more often than not, these approaches at best result in temporary progress, lasting perhaps a few days or weeks. Progress is soon reversed and you are right back on the original plateau. Eating more frequent small meals might lead to a temporary boost in metabolism and better blood glucose control, but it is unlikely to result in any permanent weight loss, once the body adapts. The least effective of the above suggestions is to wait it out. If you don’t change the input, you can’t expect the output to change. So while these recommendations might help get you started, they are unlikely to lead to permanent, long term change. But where does that leave us? Are we doomed to stay on the plateau forever?
The ‘Set Point’ theory. I discussed the Set Point theory in a previous post on the Shangri-La Diet, just one of many diets based upon the set point theory. (See: Flavor Control Diets). Set point theories trace back to the lipostatic (“constant fat”) weight control theory of Gordon C. Kennedy, based upon research he did on rats in the 1950s. Kennedy found that when he varied the caloric density of rat chow, his rats initially gained or lost weight, but they eventually adjusted how much food they ate, or their physical activity levels, so as to re-establish their original weight. Kennedy took this to be evidence that rats have an internal set point, a “natural weight” which their physiology acts to maintain against external changes to environment. The set point concept was later extended to explain the persistence of stable weights in human, in the face of variation in dietary intake and energy expenditure. The physiological explanation is that your metabolism slows when you attempt to diet and your weight drops below its set point; this also typically makes you less inclined to be active. Conversely, overeating leads to a ramped up metabolism, which puts the brakes on weight gain; it also often gives you the extra energy to be active and burn off calories. In the end, try as you might, you just can’t budge your set point weight.
The set point theory is ultimately a rather pessimistic view. (For a typical popular portrayal of the theory, take a look at this discussion of set point theory in the context of eating disorders). The underlying assumption is that each of us is born with a natural weight (or more accurately, a weight “program” that specifies a weight set point that changes as a function of age). We can temporarily deviate from our pre-programmed set point weight by extreme diets, intense exercise, emotional events or illness, but eventually we will return to equilibrium, to our intrinsic, biologically predestined set point weight. We best off not to fight our set point, but to accept it. Some adherents of the Set Point theory believe that the set point can be changed, but only by means of a sustained intervention. For example, Seth Roberts, in his Shangri-La Diet, prescribes the use of “flavorless calories” (such as oil or sugar water) to break associations between flavor and calories and trick the metabolism into lowering set point. Set point can also be changed by other interventions such as diet pills or special appetite suppressing foods. However, once the dietary or medical intervention is stopped, the set point will return to its “natural” level, and the weight will creep back on. Permanent, lasting change is impossible without the intervention, according to this Set Point theory, since progress requires lifelong dependence on some external crutch, some substance which hopefully is healthful, but nevertheless which we can never afford to go without for very long.
If you think about it and look around, it soon becomes clear that the Set Point theory can’t be right, or at least it is too simple, because it can’t explain certain undeniable facts. Despite the numerous people who have failed to keep the weight off, we all know people who have lost huge amounts of weight — and kept it off. One of the most remarkable stories is that of Jon Gabriel, who dropped from 400 pounds to a very muscular 189 pounds and published his story and his insights in a best-seller called The Gabriel Method. Many people have replicated Gabriel’s type of “non-dieting” weight loss, to varying degrees. We also know that various ethnic populations, such as Pacific Islanders and the Pima, who are healthy and trim on their native foods and in their native environment, frequently become morbidly obese and diabetic when they transition to a Western diet and lifestyle. And the American population as a whole is experiencing skyrocketing rates of obesity since the 1970s, which cannot be explained in terms of genetic programs. So the experience of both individuals and populations testifies against the Set Point theory.
And yet, there is at least some plausibility to the Set Point theory, or it would never have taken hold so strongly. There are undoubtedly periods in our lives where our weight is remarkably stable, and where we experience resistance at our efforts to lose weight or get fit. Even outside of weight control and fitness, whenever we try to change ingrained habitual behaviors, there is a strong tendency to return to where we started. In both physiological and psychological terms this is called “homeostasis” — the strong tendency of an organism to resist change. Homeostasis is generally beneficial because it helps us to maintain a healthy stability in the face of environmental changes that could be potentially detrimental or even lethal, if not resisted. But at the same time, homeostasis can sometimes be the enemy of positive changes, such as losing excess weight, or becoming more fit.
If the Set Point theory is based upon a recognition of homeostasis, a well established biological reality, what could possibly be wrong with it? Well, upon looking more closely, it turns out that the Set Point theory is based upon a serious misunderstanding of homeostasis.
What homeostasis really is and how it really works. The big mistake in the Set Point theory is that it fails to realize that homeostasis applies only to our internal environment, not to our external physical condition. The organism does not inherently defend any particular macroscopic bodily features such as total fat or muscle mass, or external fitness. What the organism defends is the internal environment, the so-called “milieu interieur“, as Claude Bernard called it in the nineteenth century. Homeostasis appropriately applies to certain essential internal physiological variables, at the level of the cell or the bloodstream: pH, the concentration of glucose (or more accurately, glucose+fatty acids+ ketones), electrolytes, and certain other essential physiological metabolites. These essential physiological parameters must be tightly controlled within narrow bounds — not as a constant, but as a range — in order to support cellular function. For example, blood glucose should be kept within the range of about 70-150 mg/dL; if it drifts outside of this range, hormones like insulin, glucagon or epinephrine will normally act to bring it back within range. If the body is unable to successfully regulate these key parameters, it may enter a state of shock and tissue damage, loss of consciousness, or death may ensue.
So if there is a “set point”, it applies not to body weight, fat, muscle, conditioning, or other outward characteristics; rather, it applies only to the inner environment of our cells and the bloodstream that nourishes them and supplies their energy. Our brain and endocrine systems don’t directly detect our weight or muscularity — they sense only what is present in the immediate cellular environment. There are certain hormones, such as leptin, which do to some extent vary as a function of body composition, but they do not do so in an absolute way, and can alter their response over time in a dynamic fashion. Body weight and fitness tend to act “as if” there is a set point only because they are influenced strongly by energy metabolism, and are linked to them in the short term. So in the short term, weight loss does tend to produce an energy deficit that is reflected by blood metabolites, cellular response, and even hunger. And in the short term, if nothing is done to change this connection, the set point theory seems to work. However, this is at best a temporary type of stability which is not centrally controlled, but rather results from a “balance of forces” that can be dynamically altered over time. Gary Taubes expressed this point well in his critique of the lipostatic set point theory:
Life is dependent on homeostatic systems that exhibit the same relative constancy as body weight, and none of them require a set point, like the temperature setting on a thermostat, to do so. Moreover, it is always possible to create a system that exhibits set-point-like behavior or a settling point, without actually having a set-point mechanism involved. The classic example is the water level in a lake, which might, to the naive, appear to be regulated from day to day or year to year, but is just the end result of a balance between the flow of water into the lake and the flow out. When Claude Bernard discussed the stability of the milieu interieur, and Walter Cannon the notion of homeostasis, it was this kind of dynamic equilibrium they had in mind, not a central thermostatlike regulator in the brain that would do the job rather than the body itself. (Good Calories, Bad Calories, p. 428).
Once you grasp this point, it becomes obvious that you can have a stable, sustainable inner environment whether you are fat or skinny, fit or flabby. On the other hand, the good news is that you can significantly change your body composition and fitness — and maintain the new state — so long as you can do so while maintaining internal homeostasis. In fact, you can make major, lasting changes to your body and fitness by understanding how homeostasis works.
A stepwise evolutionary model of plateau busting. So if we are not constrained by arbitrary set points, if our body weight, fat, and muscle composition are not predetermined at birth, why is it so hard to make progress, and how can we progress to a new state? I think the best way to answer this question is to think about how systems evolve and adapt. Adaptation is typically not a smooth, continuous process, but moves from one relatively stable state to another through a series of discrete, quantum steps. Mathematical analysis of complex adaptive systems — such as cells, individual organisms, biological species, and human organizations and economies–shows that they typically display stable “nodes” or “attractors”– states which tend to resist change — until the change is big enough, and in the right direction, to move them to a new stable state or “orbit”.
A useful analogue for how this works comes from the Darwinian explanation of how biological species evolve. Species are typically very stable in the short term (which can be thousands or millions of years on the timescale of evolution). Species resist genetic change because a common breeding population exerts conservative forces that tend to keep variation within a limited range, so the population traits remain stable. But every so often, new or divergent traits appear within sub-populations in response to environmental pressures. If such a sub-population becomes reproductively isolated for long enough, perhaps by due to geographic separation, it can continue to grow far enough apart genetically that the new sub-population can no longer interbreed with the original breeding population. In this way, a new differentiated species is born, with no “bridge” back to the original species.
Individual adaptation is of course not the same thing as species adaptation. But there is at least this much similarity: if the adaptation is large enough, and if there arise new forces which act to stabilize the adaptation, then a stable change is possible. If the stability persists long enough for the balance of forces to change, the adaptation will be “permanent”, with no easy reversion to the original state. However, some sort of “separation”, analagous to geographic isolation, is needed to prevent reversion or “backsliding” to the original state. Just as a river or ocean separating two islands can keep two sub-species from rejoining, there needs to be some type of “habit separation” between new and old patterns to prevent us from going back to where we started.
A good mental model for this is crossing a stream which is broken up by a series of large boulders. Getting from one side to the other may seem like an impossible task. It certainly cannot be done with a single bounding leap. But if the task is broken down into a series of small steps, each of which is a stable “boulder”, then it can be done. If the boulders are far apart, you may hang out for quite a while on each boulder, getting your footing and balance. But then at the right time, with enough confidence, you decide to make your move to the next boulder. Each step is still a challenge and takes some preparation, but with preparation and sufficient strength, it is within your reach. By the time you are to the other side, it is equally hard to return to where you started. Just as biological evolution proceeds stepwise, and generally without reversion, to a new space, so can individual adaptation evolve to a new stable state through a series of intermediate “resting points”, each stable in their own right. And if these resting points are far enough apart, it will be hard to return to the original place you started. But, applying this to “plateau evolution”, a stream with well spaced boulders is preferable to a stream crossed by a continuous foot bridge, because the bridge makes it too easy to re-cross the river back to where you started.
How does this look in practice? The stepwise evolutionary model is not mere theory, but something I have experienced myself. And I think it may provide a more general model of how we can adapt and bust out of plateaus that appear (but only appear) to be holding us back. The figure below shows the most recent 8 months of my weight loss. I started out at 185 pounds several years ago and just recently reached my goal of 150 pounds. But only since February 2010 did I keep an almost daily record of weights. I annotated my weight log with comments regarding various changes I made to my eating or habits, including both sustained and individual events:
When you look closely at the day by day weight measurement in any period of a few weeks, you tend to see only a lot of fluctuation over a range of about 4-6 pounds. These are plateaus. A plateau does not mean a constant weight, but rather what stock investors might call a “trading range” — a normal range of variation around some average weight. But periodically there is a move of 3-4 pounds that seems to endure, to “take”. And then there is a new average weight with a range of variation around it. These shifts may not become apparent immediately as permanent shifts in the average, because the magnitude of the shift (3-4 pounds in my case) can actually be smaller than the “trading range” variation around the old average (4-6 pounds in my case). Only after several weeks have passed, does it become clear that a new “plateau” has been established, because the weight is not going back up.
What causes the shifts? The key question is how to explain the moves to the new plateaus. From my limited analysis, I think I have an answer:
- Single, unique events are incapable of establishing new plateaus.
- Gradual, continuous changes are generally not likely to lead to new plateaus.
- Step changes in behavior are the main driver in new plateaus.
So, to look at my example, preparing for (and running) a challenging two-day relay race in late April did cause a brief and significant loss in weight, but the pounds came back quickly over the following week, even exceeding the starting point. What did cause a lasting shift to the first new plateau was permanently cutting back my consumption of alcohol from 5 times to 2 times a week. Eating a big birthday dinner in June spiked my weight, during that phase, but the effect was transient. But what had a significant and lasting effect in July was increasing the frequency of my intermittent fasting from once a week (on average) to about 2-3 times a week. Most recently, I used an extended fast of between 2 1/2 to 3 days to reach my goal weight of 150 pounds, dropping 4 pounds from my last plateau of 154 pounds. I now realize that a single big move like that will not by itself produce a permanent change. So my plan is to further extend my use of intermittent fasting so that I limit my eating to only 1 or 2 meals per day, going forward. So I will simply give up eating 3 meals a day; it will be either 1 or 2 meals (still giving me some freedom). That may have seemed extreme several months ago. But because I have approached this gradually, in small increments, I believe it will not be difficult at all.
The secret to plateau busting. To summarize, I think there are three important principles to keep in mind:
- Make a deliberate, discrete step–and write it down! One of the most important aspects of this strategy is to define permanent changes based upon discrete quantum steps, not tiny moves along a continuum. For example, rather than gradually increasing the intervals between meals, make a one-time decision to cut out afternoon snacks. Or to skip lunches on certain days. Or add an extra workout each week. Write down the change on paper in clear language. The value of doing this is that the change is conscious and deliberate, not something you slide into without awareness. Just as you pause on each boulder when crossing a stream and carefully plan your hop to the next boulder, be sure to deliberately and carefully plan each move to a new plateau, to be sure it is a step you think you can commit to. Look before you leap!
- Keep records and establish a range of variation for each plateau. Any step to a new stable plateau is not a step to a fixed and unvarying behavior. There should be a certain range of “freedom”, allowing for natural variation. You will first need a little time after each change to “discover” what the new range of variation is. And the change will be more apparent if you are keeping good records of your weight, your speed, or whatever you are trying to change. (If you see no change within a week, you probably did not make a significant change). It’s best to chart the results graphically so that you can see the plateaus and the shifts. But once you see some results, it is equally important to establish firm limits to this range and stay within them. In my last plateau, where my average weight dropped from 158 to 154 pounds, I was careful to stay in the range between 152 and 156 pounds. Whenever I got close to the high end of the range, I consciously cut back on my eating to allow the weight to drift lower. I had just enough freedom to make this new plateau comfortable, but not enough to make it meaningless. Likewise I never pushed hard to get below 152 pounds during this period. These limits or bounds provide essential “habit separation” to isolate the new plateau or habit from backsliding into a previous plateau range. Enjoy the freedom of the range, but strictly enforce the limits!
- Allow yourself adequate time on each plateau. It is very important to allow yourself enough time to “get comfortable” at each new step. Don’t push too hard or move too quickly to the next step. Habits take time to consolidate, both physiologically and psychologically. In the case of weight loss, what is really happening is that your hormones, enzymes, and other modulators of metabolism need time to re-balance, to provide the same level of homeostatic control of key energetic variables such blood glucose and fats as they did on the previous plateau. If you are using intermittent fasting to lose weight, you must allow time to up-regulate the catabolic hormones and enzymes so that they can more readily mobilize fatty acids and glucose from storage, keeping your cells and your brain happy. This adaptation can take weeks, and you might be wise to stay on the new plateau for a few months! Similarly, if you are adapting to lifting heavier weights or running faster miles, your body needs time to grow muscle tissue or increase aerobic capacity in response to the newly added stress. These changes are often imperceptible to you, but they are going on “behind the scenes”. To use the river-crossing analogy, allow time to catch your balance before you make the jump to the next boulder! But don’t stay there forever…keep your ultimate goal in mind and make the next move when you feel ready.
Understanding that it takes time to adjust to a new plateau is, I think, a key point to being psychologically prepared to handle the inevitable resistance to change that is experienced whenever we “stretch” ourselves in the effort to grow physically, mentally or spiritually. Learning to appreciate your time on the plateau — even to love it — was one of George Leonard’s great insights that can help all of us who are on the path of change, as I discussed in another post about his book, “Mastery”. But the good news is that we don’t have to stay on a plateau forever, if we understand how it works. Armed with this knowledge, we can judiciously make our move to the next plateau in the right way and at the right time.