How Much Weight Can you SAFELY Lose in One Shot?

In this video, we discuss the concept of metabolic adaptation and its importance for weight loss. We explain how understanding total daily energy expenditure and metabolic adaptation can help people develop effective strategies to continue losing weight. We illustrate this with an example provide information on the recommended rate of weight loss. Additionally, we touch on the concept of reverse dieting and how it can help negate the negative effects of dieting.

00:00 Introduction
Quick Answer
Understanding TDEE
Metabolic Adaptation
Reverse Dieting
Managing Expectations of Time
Coaching and Coaching Apps

Happy New Year, and welcome back to the Fitness Edda! I am your host, Erik Castiglione, owner and head coach of Viking Athletics, and in this installment, since it is the new year and a lot of people frequently set a New Year’s resolution to lose weight – I want to talk about how much weight you can safely lose in one shot, how to go about doing it, and why there is frequently a mismatch between what people think is happening and what’s actually happening especially if they’ve already lost weight in the past. So, before we get started, if you enjoy these videos please give us a like, give us a subscribe and comment if you have any questions. If you have other topics that you’d like to see covered, let us know! That’s what we’re here for.

So, what are we going to be covering today? I’ll give a quick answer to the question, “how much can you safely lose?” We’re going to talk about TDEE, which is your total daily energy expenditure.

We’re going to go through an example to show what it might look like for somebody trying to lose weight. We’re going to cover metabolic adaptation. It’s important to understand what that is, especially because I see a lot of people – if you’ve ever done a nutrition challenge in the past, and I know a lot of our members have – they try to do the same thing that they did previously on their own, and this time it doesn’t work. The question is why? So, understanding metabolic adaptation will shed some light on that and hopefully it will give people some strategies to continue their weight loss journey if they choose. If you’re a coach, it’s important to understand this so that you can help your clients.

So quick answer – first we need to know how long is one shot? How much can you lose in one shot? We typically don’t want to be in a caloric deficit for longer than 10-12 weeks. So, we’re talking 2.5-3 months tops. A quarter of the year. Any longer than that and you’re going to run into some severe side effects. And we’re going to cover that when we get to metabolic adaptation. So how long is one shot? No more than 12 weeks. What is a safe rate of loss? 0.8 to 1% of your total body weight per week. So, what does that come out to? 10% of your body weight. You should lose no more than 10% of your body weight in one shot.

A caveat to this is if you are dealing with a client that is severely obese. The more weight you have, the more weight you can lose in relative terms. We say 10% because a 300 pound person can lose 30 pounds in one shot safely. A 150 pound person probably isn’t going to lose more than 15 pounds in one shot. Going back to the 300 pound person – it is possible, depending on what their habits are, and what their body composition is, it is possible that they might lose more than 10%. Especially if they’re brand new to training, and they don’t have a whole lot of muscle mass, but a ton of adipose tissue. So, we say 10% to be on the safe side to prevent severe side effects, but if you are heavier, you might be able to go a little bit more.

So TDEE – Total Daily Energy Expenditure. What is this? It is the total amount of calories that you are burning in a day. And if we look at the chart, the breakdown, there’s four components to it. Your Basal Metabolic Rate, your BMR, is the biggest component of this for most people. You’ve got your Thermic Effect of Food which can account for about 10%. That is the energy that it requires to break down and digest and absorb the nutrients out of your food. So, I’m sure people have heard it takes money to make money, same thing. It takes calories to break down food into calories, that accounts for 10% of your daily expenditure.

We’ve got Non-Exercise Activity Thermogenesis or NEAT, and we’ve got EAT, Exercise Activity Thermogenesis. So, a lot of people think the more that they exercise, the more calories they’re going to burn, and they can lose weight that way. To a certain extent, yes. I don’t like to include that in my calculations for people. “Ok, I burn 500 calories today, so I can eat 500 calories to offset that.” We frequently overestimate how many calories we burn by doing exercise. None of the trackers are accurate when it comes to that. Especially because, and I’ve covered this in previous videos, the more you exercise, the more efficient your body becomes at exercising, and the fewer calories you’re going to burn doing that same exercise. So, I don’t like to use that. I’m glad this chart lists that as only 5%.

Non-exercise activity thermogenesis – we include walking in this. Walking for most people does not elicit enough of a heart rate change to count as actual purposeful exercise. But at the same time, it does elevate your heart rate a little, it gets you moving, it’s good for blood flow – there’s a slew of other benefits associated with it. And it can count, it says on the chart here, 15%. If you are working a manual labor job and you are averaging like 30,000 steps a day, it can be up to 50% for some people. So, there’s a lot of wiggle room there. That will be important later.

But why do we care about TDEE? In order to gain weight, I need to consume more calories than I’m expending. So, if my total daily energy expenditure, I will make it easy, is 2000 calories – if I’m eating 2000 calories I will stay at the weight that I’m at. If I’m eating more than that, I will probably gain weight. if I’m eating less than that, I will probably lose weight. Now, there is an important caveat to that. Your TDEE is a range, not a number. A lot of people think of it as one number right here. So, my red dotted line is my TDEE. And if I’m even 5 calories above that on a consistent basis, people think I’m going to gain weight. But no, that’s not the way it works. It’s more of a range – I’ve got an upper bound and a lower bound shown here. Anything that falls within this range as long as we’re hovering along this line isn’t going to change your adipose tissue. You’re not going to gain weight; you’re not going to lose it. So, you can have one meal in a blue moon – you know a steak is very caloric – but let’s say you treat yourself to a nice steak dinner. A ten ounce strip steak has over a thousand calories in it. So, if I have that, plus appetizers, plus sides, plus a dessert, plus a drink, it’s extremely easy to hit four to five thousand calories in a meal. Doing that one time – my body is going to force me back into this range here we live.

It’s called homeostasis – it’s the way things are. You have these buffers, and you have checks and balances in your body. The body does not want to change – it wants to stay where it is. So, it’s an equilibrium state, and as long as we are consistently within this range, we’re good. If I go above or below for one day, I’m going to bounce back into that range. In order to change anything, we

need consistent overconsumption or underconsumption. Consistency is key here.

The way I like to think of this is like water. In order to change water into water vapor, in order to evaporate water, I need to boil the water. That means I heat the water to 212 degrees Fahrenheit. and once it’s at a rolling boil, what happens? Nothing, initially. The water is still boiling, but it takes more energy to get that boiling water to evaporate. And you don’t see anything until it happens. So, if I’m in this range here, and I’m going up and up and up, and I’m at the upper bound, and I’m slightly above it, until I get far enough above this bound, I’m not going to gain weight.

Or better example – since we’re talking about weight loss – if I’m below this bound, I have to stay under it long enough to force a change. It’s the same thing, it’s all energy. My background in engineering and college – I was studying nanotechnology – we did a lot of quantum states, energy states. Another perfect example – you have a discrete range where I can only exist at this bound. And then I apply more energy, and nothing happens. I apply more energy, and nothing happens. I apply even more energy, and then I suddenly jump up to this bound. And then I apply more energy, and nothing happens, more energy and nothing happens, and then I’m up to the next state. To me, that’s another helpful example. It’s a way of understanding this feeling that nothing is happening, until it does. It’s that energy storage or that lack of energy consistently over time that forces change.

So, here’s an example:  we calculate total daily energy expenditure. Again, it’s all an estimation. We use people’s body weight, and there are numerous ways to do this. For the purpose of this example, I’m using simple numbers. With actual nutrition clients, I have them go through a body scan, and based on lean muscle mass and total fat mass, we can produce a little bit more pointed of an estimation. And then of course, activity levels play into this. So, we’ve got an active, 250 pound male. This would be somebody that is actively training for an hour or more 4-5 days per week and averaging over 10,000 steps a day on top of that. We would use a multiplier of 15. So, to estimate how much energy they’re expending, body weight times that multiplier gives us 3750 Calories. So, this person can eat close to 4000 cal and not gain any weight.

In fact, for the intense exercise that they’re doing, we want them to be eating that. Which goes to show for a lot of people, you are probably undereating if you are very physically active.

That’s a widespread problem in the CrossFit world. Anytime we’ve done a nutrition challenge, it is amazing how many people start eating it at what we are recommending for them, and even in a weight loss phase, the calories that we are prescribing are higher than what they are doing now. And they eat more, and they lose weight, and they don’t understand it. We’ll get into that with metabolic adaptation, but point is, we have our baseline for this: 3750 calories

The male’s goal is to lose 25 pounds, or 10%, down just over 2 pounds per week. 1 pound of body fat is roughly 3500 calories, so if I can lose 3500 calories, if I’m in a net deficit for a week of 3500 calories, I’m losing 1 pound. Since our goal is 2.08 pounds per week we need to be in a weekly caloric deficit of 7280 calories. If my maintenance here is 3750, and we subtract 1040 from that, I get 2710 calories. So, for this person, we would put them in a deficit of 1040 calories by consuming 2710 every day. That is the goal.

Continuing this example, after 12 weeks, assuming everything works out nicely, they’re down 25 pounds and they are now at 2710 calories per day. But  if we look at that new bodyweight, and their multiplier was 15, if we divide current calories by 15, that brings us to a bodyweight of just over 180 lbs. If we divide their calories by their current bodyweight, we see that their multiplier has gone from 15 down to 12. So, what gives? Are we going to continue to  lose weight after 12 weeks if we keep them at 2710 calories? Maybe for somebody that is that active. But probably not. We can’t lose weight indefinitely. A lot of people think they can continue for year after year in a deficit. If that were true, we would eventually weigh zero pounds. Which sounds silly, but if you think about it, it makes perfect sense.

The body does not want us to starve to death, so weight loss will be curbed. In this case, we now have a mismatch between their multiplier, and their bodyweight, and their calories. In order to explain this, we need to understand metabolic adaptation.

So, what happened is, over the 12 weeks, their total daily energy expenditure has decreased. And that makes perfect sense right? They were at maintenance at 3750, they’re now at maintenance at 2710. And what does maintenance mean? It means you’re no longer gaining or losing weight.

So how does that happen? Your BMR drops. Your basal metabolic rate slows down. What is BMR? If you laid in bed all day and did nothing, that’s how many calories you would burn. Your body will shift energy from non-essential processes, or it will become more efficient at them in order to expend less energy. The extreme example that I always use for this is when you have a teenage female with an eating disorder. She may lose her period because menstruation is non-essential compared to survival.

So back to our example -while my activity multiplier was 15, I’m now burning fewer calories because I’ve been in a deficit for so long, so my multiplier has now dropped to 12. It makes sense. My energy expenditure is going down to compensate for the fact that I was eating less. We see this not just after an initial period of weight loss ;it continues over time.

Back to the people that have attempted to lose weight in the past, and dropped weight, and then gained it back. That can be explained away by your fat storage being primed, and then you are now back at a higher body weight with a lower total daily energy expenditure. So, you may shoot back up to your initial weight or beyond.

Going back to our example we had a 250 pound man drop to 225. Let’s say post diet he throws caution to the wind and goes back to doing what he was doing. This is where we get yo-yo dieting comes from. Because he’s primed for fat storage it’s actually going to be easier for him to gain weight than it was previously, and he may end up weighing 255-260. This is why the biggest loser doesn’t work. Not to scare anybody, but we see this most frequently happen with people that do extreme weight loss – more than 10%. Also, it’s for people that, just after a weight loss phase, throw caution to the wind and go back to doing whatever fuckery they were doing  in the first place.

So how do we combat this? How do we get that multiplier back up to 15? We need a maintenance phase, also known as a reverse diet. We’re trying to get the mirror image here, where we increase the daily energy expenditure without increasing our bodyweight. In order to get this, I need my calories to stay towards the upper limit of my range – that upper bound. I want to stay in this bound without going over, and we’re going to do this through a planned caloric increase.

 So, how long does this entire process take? That would be a pretty fast fat loss phase, 10% in 12 weeks. You’re going to maintain 2710 calories for an additional 2 weeks after that. You may even see some continued weight loss. But we want to maintain the calories there and then we’re going to reverse diet for at least 12 weeks. I picked 12 weeks in this case because It’s at least a one-to-one ratio We want to maintain the reverse diet for at least as long as the fat loss period, if not one and a half times to two times as long.

So, what we do here is we need to calculate the target goal for calories at current weight with a multiplier of 15. It gives us the increase we need – 665 calories. Divide that by twelve weeks, and I’m increasing my intake slightly. So, 55 calories per week. We’re nudging up in that direction. And, if you do this, we can get our total daily energy expenditure to increase. This is how you kind of speed up your metabolism. Again, if you look at the shape of the graph, it does level off up here. There is an upper limit to how much you can increase your total daily energy expenditure before you start gaining weight.

As I said in the beginning, the body has a range, an equilibrium range where it likes to exist. We call that homeostasis. The body doesn’t want to change, so we can nudge ourselves upward in that direction, and increase calories to the point where bodyweight just starts to increase at the end. And that’s how we avoid the yo-yo that we get with crash dieting.

It’s a slow process. All said and done here, we’re looking at 3 months of weight loss, 2 weeks of maintenance, and 3 more months of reverse dieting. Do the math – this is a total of 26 weeks. That’s half a year. This is how we get long-term, sustainable results. There are other ways of calculating the increase where you use a kind of a compounding effect instead of a strict number. If you do the math here, a 55 calorie increase from 2710, that is a 2% increase. And it ends up being less than 2% once I get to 3000 calories, and I’m increasing from there by another 55 that’s less than a 2% increase. There are ways of doing this where you’re doing a percent increase each week, and that can work too. I just picked this method for ease of following math. Again, there’s multiple equations to estimate total daily energy expenditure.

The biggest thing is to monitor the scale. That’s going to tell you what’s going on. So, if you have a check in day, one day per week, and keep it the same day, same time each week, you monitor trends. And that will let you know what’s happening. Are you gaining? Are you losing? If you’re going to weigh yourself every day, that’s fine. Just make sure that you are using that check in day from week to week to analyze trends long-term. There’s a lot of daily fluctuation that can occur. If I have a salty meal and I’m retaining water, If I had a higher carbohydrate meal, anything like that, I’m going to store water in my muscles. My glycogen stores are topped off. For ladies, if you are menstruating, you are going to likely retain weight before and during, and then after, your weight will go back down. Important things to consider when you are monitoring your weight.

What is the end all, be all take away message here? Fat loss is a process. It’s not going to happen quickly. For minimizing the effects, the metabolic adaptation, we want to lose no more than 10% of your body weight over 12 weeks. Then you are going to go into a maintenance phase, and then a reverse dieting phase  to try to bring your calories back up. And it’s going to take honestly half a year at least before you can start another fat loss phase. If I am a 350 pound male and I’m trying to lose 200 pounds and get down to 150, it’s going to take years. If you set yourself up with that expectation, and I’m doing three months of loss, reverse diet, and then I go into another fat loss diet where I lose another 10%, etc., you’re going to have sustainable results. It’ll keep the weight off, as opposed to trying to do too much, too fast, and then you end up messing up your metabolism.

So, I know of people that are hovering around 200 pounds, and they’re eating 1800 calories, which, I’m going to do the math here quickly and say the person is active, at least 3 times a week – we’ll use a multiplier of 13 to be conservative. Maintenance at 200 lbs that level of activity should be 2600 calories. They are 800 calories below that. Why? Because of metabolic adaptation. If you are struggling to lose weight, and you are feel like you are eating, you know, we’ll see with ladies especially, they’re down to 1200 calories – and you should never be below 1200 calories a day ever -but we’ll have people on 1200 calories and they’re not losing anything, it’s because of metabolic adaptation. So, what we need to do is figure out what your maintenance should be, and go from where you are, to try to increase up to that. So, if you’re already pretty low on your calories, and you’re not losing, you need to do a reverse diet now, and then you can start fat loss from there. So that’s the name of the game.

There are numerous ways to get this done. If you are really stuck, hire a coach. That’s what we’re here for. There are other apps that are called quote unquote coaching apps, and the difference between a coaching app and a tracking app is that a coaching app will adjust calories from week to week based on what you are inputting. It does require you to track your food, it does require you to weigh in at least once a week.

There’s 3 that come to mind for coaching apps. MyFitnessPal is not a coaching app, it’s just a tracker. Daily macros was another one – there are several tracking apps. The 3 coaching apps that come to mind are Renaissance Periodization, Carbon Diet App, and MacroFactor. What they can help with is straight up macro calculations, and calorie calculations, and as you check in that will change based on the goals that you input. What they do not help with are recipe suggestions, and how to overcome obstacles that you might have. So, if you are somebody that travels a lot for work, and eating meals at home, preparing your own food is not a viable option, this is where a human coach can help. We are here to problem solve for you and produce strategies and workarounds that are going to work for your lifestyle. If that is not a concern, have at it with the with the coaching apps.

What’s the difference between them? I have personally used Carbon and MacroFactor,

and I am not endorsed by anybody, this is just me relating my own experience, I did not find Carbon to be very intuitive. I find MacroFactor to be very intuitive, and I can tinker with things, and it works better for me.

Carbon was created by somebody that I really respect – Dr. Layne Norton. I literally just heard him describe this, and I had to laugh. When asked what the difference is between them he said it’s Apple versus Android. He said with Carbon, they don’t really allow you to tinker. It’s a simple to use, plug and play, Apple like ecosystem. MacroFactor is more like Android – you can play with it more. I personally like to tinker, and I do not find Apple to be intuitive whatsoever. I can’t stand the ecosystem, never mind my loathing of the company, I won’t get into that, so it makes perfect sense to me that I would gravitate more towards MacroFactor.

As far as the Renaissance Periodization app is concerned, I have not used it personally. My last experience with it was with a gym member that I had that was using it, and this was pre-pandemic. I really hope they’ve updated the app since then. Based on what he was telling me, their calculations were solely based on your check-in day as opposed to the trend from week to week. If you were weighing in every day and then you had a day where you weighed in high, and that happened to be your check-in day, it would automatically cut calories. Especially your carbs, which as a lifter/CrossFitter was not beneficial for this person. It got to a point where he was extremely low carb and not performing well. It also didn’t help that his check-in day was Monday. I don’t know if he had access to change that. That’s why I’m hoping that RP has updated the app. This member was using the app during football season, so every Sunday was pizza, wings, and beer, and even if he was in his caloric range, he had a lot of sodium and ballooned up for weigh-in day.

As a result, the app just kept cutting carbs cutting carbs, and cutting calories. Again, it did not analyze all the data from the week. If you’re only looking at one day, that doesn’t tell you whether or not you’ve gained weight. Regardless of whether you’re working with a coaching app, human coach, or doing it on your own, you need to look at trends from week to week. Day to day is helpful as well, but also keep in mind what it is that you’re eating and know that you can fluctuate in water weight 5 to 10 pounds in a day. It’s not uncommon based on everything that’s going on.

I hope you all enjoyed this video. Give us a like, give us a subscribe, again if you have questions, comments, you want to see something else covered – that’s what we’re here for. We’ll see you guys next week. Thanks for tuning in!


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