In general, do you need to be in a calorie deficit to lose bodyfat? Yes.
Is it as simple as "3500 kcals is 1 lb of fat loss?" No.
Does the magnitude of the deficit lead to a rate of BW and fat loss that you would expect based off simple formulas and calculations? No. In fact, my experience is that especially after a massive refeed/cheat, a larger deficit (like 1600 kcals/day instead of 1800 kcals/day intake) gets me back to baseline (and below) way faster than what calories-in-calories-out would predict.
And for the grand finale...see below:
Q: I have read numerous threads in this site, trawled through other forums and websites but can't find a discussion or answer to the following:
Please correct me where I am wrong as I am keen to learn more on this...
Thermodynamics is essentially at play with calories in and calories out. We cant create energy out of nothing but we can transfer it. Therefore weightloss (ideally fat loss) comes about via being in a deficit.
Hypothetical example: If a person has a maintenance intake of 2500 calories per day , the only way to ensure this person can Skipload and still lose weight is to create a calorie deficit over the 6 days that is greater than the calorie intake over and above 2500 during the Skipload day.
E.g maintenance = 2500 cals x 7 = 17500 cals per week.
Implement a 800 cal deficit for the first 6 days = 1700 cals per day.
The Skipload day needs to be less than 2500(maintenance) + 6 x 800( our daily deficit).
I know the Skipload is not a numbers based protocol but I havent seen it discussed how people approach the first 6 days and still ensure the weekly deficit and it is this I am interested in.
Look forward to hearing thoughts and discussion on this."
Skip's answer:
"Great question but one that a lot of people don't like the answer to because it isn't as black and white as the numbers. In fact, if we go by JUST the numbers, it simply cannot work, and yet it does.
Though skiploads change from person to person, there are plenty of people who can load for 3 meals over 6 hours and this is a pretty average skipload time. At any given time in the last 20 years of doing what I do, roughly 50% of my clients will be loading at 6 hours. However, there are others who will load at 12 hours or more. Even if you take a look at any other trainer who might allow a cheat meal every now and then, that one cheat meal will also surpass any caloric deficit for the week, if you are approaching it strictly by the numbers. So, what is really going on?
The best I can do is give you my opinion based on doing this for almost 20 years (started in 2002).
Here are a few points that are important in understanding how it works:
Calories in and calories out doesn't work in a situation like this. It can't. Anyone who says it can or that it does, is just plain wrong. As I said before, the numbers prove this. Otherwise, there is no way anyone would get lean, let alone ripped to shreds. Calories in and calories out is a rudimentary way to understand WEIGHT loss. What we are doing with skiploading—as bodybuilders—is not as simple as weight loss. It is about body fat loss and either maintaining muscle or even gaining muscle at the same time. This is where hormones comes into play, timing comes into play, etc. I know a lot of people disagree with this but my response to them is, "explain how skiploading works as well as it does." They can't do that. Let me take that back; they will TRY to explain it, but it makes no sense and isn't logical.
One of the things that is crucial to successfully getting lean while skiploading is the fact that you need to be glycogen-depleted. This alone will help to cause super-compensation from skiploading. Without getting into numerous paragraphs to explain this, it's a situation with insulin sensitivity, replenishing glycogen stores, and amping the metabolism. Kind of a 2-steps-forward-one-step-back concept.
On it's own, the above doesn't explain why the numbers don't work. It needs a second part and this is the caveat to the entire thing and it is and will be argued ad nauseam:
The body can and will get to the point where it cannot fully digest all of the food ingested. For a short skipload, this likely doesn't apply. For longer skiploads, it absolutely can. Look at it this way and anyone who has experience with long skiploads will back this up: you will get to the point where food coming in has to basically push food out the other end. The food either moves through the system quicker and/or the volume of food is so large that it can't process and assimilate all of it. People who have experience with very long skiploads will report more pale-colored feces later in the skipload. This is because the amount of food overwhelms the liver's ability (and the gall bladder) to provide enough bile salts. When there isn't enough bile salts, the body cannot break down fats as easily or efficiently. Those fats pass through the digestive system not being fully digested and assimilated. In short, this means these calories do NOT count because they weren't digested to be counted as a unit of energy. Most people believe that as soon as you eat something, the calories count. They certainly don't count if you throw them up or they move through your body without being fully digested.
The next question should be obvious: why would someone eat so much food if it isn't all digested? The reason is because when you are very depleted, you can either guess at the amount of food you need and hope you are right, or you can saturate your system with calories knowing that you are maximizing the amount of food your body is able to process. The latter means that your only limitation is what your body can handle—digest, assimilate, and use.
When you put together these 2 "caveats" above, you have a situation where you are maximizing glycogen storage, maximizing recovery, and maximizing the amount of calories that your body can use during the skipload. The more calories you get in, the more "gas" you are pouring on your metabolic fire for the following week when you go back to regular dieting. Yes, you can overdo the skipload, so there is a point where it is too much and body fat can be stored. This is why the skiploads start small and you build into larger skiploads over time. It is also why it is important that someone with a lot of experience with skiploading is dictating how long and how much to load. Someone like, say, me.
To circle back to the point of the caloric deficit and the numbers not working, even without all of the calories "counting" from the skipload, there will still be an extremely large amount of calories that cannot be explained away with numbers (in reference to x amount of a caloric deficit). The explanation that I have given is the best I can do right now. It would take a lot more knowledge and a lot more science to get into the exact reasons, but I am confident that my opinions above explain probably 90% of what is going on. The other 10% will be explained by someone else who is smarter than I am and probably much younger than I am. I say younger because I don't think there is going to be a black and white explanation for why or how it works for a while. I think we have to learn more about the relationships between food intake and hormones to know the exact reasons why it works."