The body is a thermostat. Everyone has a set point where their body wants to be as far as weight goes. It is something most of us have probably heard, since we're into physique and lifting. The majority of people have never heard this and have no idea what this means though.
This set point is one of the big drivers of our appetites (when we are properly using our bodies, more on that later). It is also independent of your mind and anything else. No matter how bad you
want to gain/lose weight in your head, your body doesn't care. The body has this set point where it says, I want to weight 215 lbs and if my weight goes above or below that by more than a couple pounds, I am going to mess with hunger to ensure the owner of this body eats less or more accordingly. That is why as you lose weight during a cut, it gets harder and harder as you lose more and more weight. You appetite gets stronger and stronger. That is also why during a bulk, once you've gained 20 pounds in the last few months or so, many people start finding it harder to continue eating at the surplus level (and particularly to continue to increase their surplus) they need to continue gaining weight.
This is also why SO MANY of the billions of obese people on this planet struggle desperately to try to lose even 10-20 lbs. They might have 100 pounds of fat around their abdomen and 40 more on their ass cheeks, but once they lose 10 of those pounds, they start feeling hungrier and adhering to their diet becomes nearly impossible.
The body isn't saying that this is the
healthiest weight for them to be at. It isn't saying they shouldn't lose weight, but when the body loses weight, it gets scared. Scared that it is going to starve to death. Our evolution has not caught up to the overabundance of food that the majority of the developed world has nowadays. However, it is very possible for us to change this set point and allow ourselves to gain/lose weight in a sustainable way. All you need to do is buy my book for 5 easy payments of $25.99...
So what is the mechanism behind this thermostat?
Well, we actually know a fair amount about how this works. There have been a few studies done on the matter, so I will link them here then summarize where we are at today:
1.
How the skeleton reacts to changes in body weight
2.
What is Leptin?
3.
Leptin and the regulation of body weight in mammals
4.
Body weight homeostat that regulates fat mass independently of leptin in rats and mice
- There is a TON of other studies on
leptin regulating body weight,
mutations that alter leptin production to cause obesity, and much more.
Based off some of those studies, there is evidence of bone sensing body weight on multiple levels:
1. Each individual bone senses the load against it and adjusts its density accordingly. The principle behind this is known as Wolff's Law and "the Mechanostat." The more time under tension as well as the amount of tension a bone is put under, the greater the bone mass in that area. For example, the femur is a very long bone that experiences a lot of sheer force from walking, running, biking, getting up and down from sitting/laying positions, and even many sex positions !(hey guys I'm trying to make this a fun lesson here!). The arms however, are loaded much less. Under normal natural circumstances, very few positions really stress the arms, mainly just carrying things and going prone perhaps during hunting or other activities (cough SEX cough).
The key here is that it is both time under tension as well as load. So an obese person who sits all day might have really poor bone density, whereas an obese person working at a job where they stand most of the day would have much higher bone density. Similarly, military guys doing ruck marches are going to have super dense leg bones compared to someone who just walks around normally. The more time you spend on your feet, the higher the bone density will be in your lower extremities. Weightlifting also increases bone density. You may have seen videos of powerlifters benching where their arm bones are literally
bowing outward as they lift incredible weights. You bet their bones sense this and will automagically increase bone density the more and heavier they lift. Thankfully bones are quit forgiving, nature and evolution has given us this amazing substance called bone which is both quit flexible and also extremely sturdy
2. There is a set point in bone too as far as the strain they aim to experience. This set point is "remarkably similar across different species and activities measuring approximately 2–3000 με (2–3 × 10−3)" (
1). As mechanical loading increases, bones formation will occur to make the bone stiffer, thus reducing strain on the bone and making it so future loads of the same weight don't overload the bone and instead cause the target set point strain.
So points 1 and 2 above demonstrate that our bones sense our body weight and respond accordingly by increasing or decreasing bone mass in areas under mechanical load. This lays the baseline for the information that is coming next, which is why we're all reading this (or at least hopefully you're reading... don't forget to buy my book!)
3. Now, getting to the hunger and weight side of things. Leptin is a hormone released by adipocytes (fat cells) and plays a very important role in our body's ability to maintain homeostatis (
2). Leptin plays many roles in the body, but we are just going to focus on one:
leptin tells the body it is satiated. This is the opposite of ghrelin, which tells the body it is hungry.
- A shortlist of things that increase leptin (making you less hungry): eating; overfeeding; glucose/sugar; amino acids (protein); insulin; glucocorticoids; estrogens.
4.
The key finding to this whole body weight set point principal is that mechanical loading of bone ALSO effects leptin levels. That is what is demonstrated in study 4. This study is fascinating and I encourage that you read it. However, I can summarize the results here: our bones sense how much we weigh and not only manage bone mass accordingly, but also regulate leptin levels. Thus, when the bones sense that he body has recently quickly lost weight, it will increase hunger in an attempt to gain it back. When the body senses it has quickly gained weight, it will decrease hunger in an attempt to lose it. The body doesn't want to gain more weight and the body also doesn't want to lose more weight. It wants to maintain homeostasis.
Now, this is a critical finding and paves the way for a bunch more incredible information:
The body is a thermostat. These studies have proven it. The body says, I have weight 200 lbs for the last 3 years and I want to continue to weigh 200 lbs. HOWEVER, we can change this. The thermostat setting can be moved up or down, but it must be done with that. Many of us have experienced the difficult I mentioned earlier. The body will do ALMOST ANYTHING to maintain homeostasis. When you are deep in a cut, getting down into that sub 10% body fat range, your body starts to FUCK YOU in an effort not to lose any more weight. It ramps up ghrelin production and reduces leptin to make your hunger go through the roof, it starts to subconsciously reduce your NEAT (non-exercise activated thermogenesis, stuff like fidgeting, wanting to get up and walk around) and make you more sedentary to preserve energy, it starts to fuck your hormones up, reducing androgens, thyroid hormones, all sorts of things. It will do anything to get back to where that set point is. Likewise, if someone gains a lot of weight, the body will often do what it can to burn calories: increasing NEAT; changing hormones accordingly; and reducing appetite.
The thermostat isn't like the one on the wall where it is EXACT. There is a tolerance in either direction of some number of pounds (or kilograms, if that's your thing). So your body wants to weight 215. Well you might take a big shit and that puts you down to 212. Your body doesn't freak out and tell you to eat more; the body is fine with that little fluctuation. Nobody knows exactly what the tolerance level is in either direction and it also could (and probably does) vary based off individual. Some people might be more sensitive to weight loss than others. Others might be more sensitive to weight gain. Some might be really sensitive to both.
Now, the key to changing that set point is to change it SLOWLY, SUSTAINABLY, and SMARTLY.
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SLOWLY: as I said, the body has a tolerance for weight loss/gain in either direction. By changing your weight more slowly, your body is able to adjust to the change in weight. If you gain 0.5 or 1 pound per week for, or lose 0.5-1 pound per week, usually the body can deal with that kind of thing--at least for a while. 3 months down the line when you're 15 pounds heavier or lighter, the body might say, hold up, this is getting to be a little too much. This is where diet breaks can be helpful. Go up or down in calories to your new maintenance level and let your body adjust to this new point you're at. Most people have a higher tolerance for weight gain than for weight loss, especially guys like us with already low body fat levels.
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SUSTAINABLY: making sustainable diet choices is critical when you're trying to change your set point. This goes hand in hand with doing things slowly. Not only is there the actual physical aspect to weight gain/loss that I have discussed all this time, but there is a-whole-nother world to weight loss that is the psychological side. So many people struggle to cut out sugar, or stop drinking soda, or whatever. Forming new habits is critical AND can take a
really long fucking time! For someone who is used to eating sugars for the last 10 years, for them to cut that out is going to be really hard, not only is
sugar addictive, but you are changing your habits too. Making sustainable changes in a methodical manner is critical to success.
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SMARTLY: There are things we can do to beat the body. The body is a genius, but the body is also limited in that it can't
think. It just does this stuff automaticaly. The rest of this post is about the tricks and shortcomings of this whole process.
So skeletal loading alters hunger. Well, one of the huge shortcomings in that is due to our evolution and modern society. Humans were never meant to sit in a chair all day. We were meant to be standing, squatting, walking, running, carrying things around--basically mostly doing
anything but sitting/laying down. Now, a vast number of people work desk jobs and a concerningly large number of people don't do any physical activity at all, they just watch pathetically bad TV shows and rot their brain with social media and the news. Well, when we sit, that means our skeleton is
not loaded!! This means that the whole feedback loop of the bones sensing our weight, changing bone density and increasing/decreasing leptin accordingly STOPS HAPPENING!!! So for someone who is working a desk job, they might be gaining a ton of weight, but their appetite is solely driven by blood glucose levels and sugar addiction.
For body builders, this means a few things can be done to help "trick" the body into making our cuts easier. This hypothetical/theoretical, but it makes sense and I've seen these points backed up by anecdotes:
1. Sit more. That feedback loop that breaks when sitting goes both directions? So the office worker who is getting morbidly obese because their leptin signaling is broken (and they are likely resistant to leptin, just like insulin) could go the other direction too. As we start to lose weight, if our skeleton senses that weight loss because we are standing or walking all day, it will lower leptin, causing us to be hungrier. Most successful body builders I know follow a cutting schedule like: lift
X times per week, do their allotted cardio, then just chill. I've had some friends tell me that they find cutting easier when they bike more instead of run, which makes some sense as you're loading your legs via the bike resistance as well as sitting on the seat.
2. Increase gravity. You can control gravity right? By increasing gravity, you become heavier, so your body will...just kidding. HOWEVER, what you can do is
try wearing a weighted vest! By wearing a weighted vest--it doesn't have to be much, just like 5-10 pounds, you are tricking your skeleton into thinking you weigh more than you do--that you aren't losing weight like you are on a cut. Thus, that feedback loop is
hacked and your cut can become that much easier. I have also seen this backed up by a couple guys, one wore a 7 lb vest and the other wore a 10 lb vest, both of them said wearing vest seemed to cause that cut to be the easiest one they've ever done.
- Now, the downside is once you take that vest off, the feedback loop is activated again. So perhaps this is really only a good tactic to use for something like a photo shoot, competition, or porno video shoot where you wanna be lean as fuck on camera (lol). Otherwise, you'll be stuck wearing a weighted vest for the rest of your life lol.
3. Bulk then cut. I always see people ask, should I bulk or cut? Unless you're at or above 20% body fat, IMO you should always bulk first. By gaining 10-20 lbs of mostly muscle in that 12-16 week bulk cycle (or whatever length it is), the weight gained will put you above your body's set point. So you're setting yourself up to be able to cut successfully afterwards. Once you've gained that muscle, your BMR goes up, you can start standing/walking more and your appetite will go down, making it easier to cut. You can then lose weight (again, slowly and sustainable) and get yourself back down towards where your set point is, but only with more muscle and less fat!
That's all I've got. Hope you found it interesting!