YouTube tutorial explaining a theoretical upper limit for fat loss based on a 2005 analysis by Dr. Alpert: the body can burn fat at up to 31 calories per pound of body fat per day before muscle loss accelerates. The presenter demonstrates how to compute the maximum daily calorie deficit and converts it to weekly fat loss using 3,500 kcal ≈ 1 lb fat (examples: a 200 lb person at 20% BF → 40 lb fat → 1,240 kcal/day → ~2.5 lb/week; a 170 lb person at 15% BF → 26 lb fat → ~1.6 lb/week). The video then outlines how to target this deficit (eat below TDEE, resistance training, cardio), advises recalculating as you get leaner, warns that the approach is aggressive and hard to adhere to, and promotes the Built With Science programs for individualized guidance.
Questions this video answers
31 calories per pound of body fat per day.
Approximately 3,500 calories equals 1 pound of fat.
40 pounds of body fat.
1,240 calories per day.
About 2.5 pounds per week.
When it comes to fat loss and even achieving a six pack, most of us want results as fast as possible. In our eyes, the faster we can burn off our excess fat, the better, right? Well, not really, because what most people don't realize is there's actually an upper limit as to how much fat you can lose every week. And if you try to push past this weekly limit by doing more cardio or eating even less, for example, then you'll now start to lose substance, substantially more muscle instead of fat. Do this for months on end, which many people unfortunately do, and you'll eventually end up with a skinny fat physique with too little muscle and still too much fat. So now the real question becomes, what's the most amount of fat you can lose per week, while minimizing muscle loss in the process, as this is going to better enable you to attain the lean muscular physique you're after instead of just winding up skinny fat. And to answer this question, we'll use the findings of a 2005 paper by researcher Dr. Alpert, who analyzed several fat loss studies in an attempt to quantify the maximum amount of fat one can lose per day without excessive muscle loss. What he found is that the body is capable of burning body fat to use for energy at a maximum rate of 31 calories per pound of body fat per day. Once you exceed this rate, the body then has to tap into your muscle mass in order to make up for its energy needs. And although the study is theoretical and does have its limitations, when you crank out the numbers, they actually align well, with both past research on the topic and with my own experience as a coach as well. But to put this theory into perspective for you, let's use an example. Let's say John weighs 200 pounds and is at 20% body fat. Multiply these two numbers and we can determine that John has 40 pounds of body fat. Multiply this by the maximum rate I mentioned earlier of 31 calories per pound of body fat, and we get 1240 calories. This represents the maximum daily calorie deficit John should employ every day to maximize fat loss while minimizing muscle loss. And to find out what this would equate to in terms of pounds of fat loss per week, we can multiply this number by 7 to represent a week, and then divide it by 3500. Since we know that this is roughly what 1 pound of fat is equivalent to. And as you can see, we, we end up with 2.5 pounds, which represents the theoretical maximum amount of Fat Jon could lose per week while minimizing muscle loss. Whereas on the contrary, if you're a leaner individual like Jimmy here, who weighs 170 pounds and is at 15% body fat, then in this case, he'd only be carrying around 26 pounds of fat, and therefore his theoretical maximum rate of weekly fat loss would be just 1.6 pounds per week. So, as you can see, as you get leaner, the maximum amount of fat your body is able to lose per week reduces, which is something that other papers have found to be true as well. So now that we've covered what the maximum rate of fat loss is per week, how can you now go put this into practice? Well, if you're truly seeking to lose fat as fast as humanly possible, then here's what you do. First, find out what the maximum daily calorie deficit and weekly fat loss number would be for you using the process I outlined earlier. And then to achieve this daily deficit, you would use a combination of eating below your TDEE or maintenance calories, performing regular resistance training, and throwing in additional cardio. And then you simply monitor your body weight throughout the weeks and try to hit your target maximum weekly fat loss number. Then, as you progress and your body fat continues to decrease, you'd want to slow down your rate of fat loss to minimize muscle loss by again, recalculating what your maximum weekly fat loss number would be at your new weight and your new body fat percentage. So over time, the rate at which you lose weight should slow down, and basically, that's all there is to it. But with all that being said, I do want to provide some precautions. First of all, keep in mind that this protocol is a very aggressive approach that employs a fairly large calorie deficit, high activity, and a fast rate of weight loss. For some who are more experienced, this may be completely doable. But for most people, especially those just starting out with their fat loss journey, it's just unrealistic and very difficult to adhere to. And you'd be much better off taking a longer, less aggressive approach that you'd be more likely to stick with. Second of all, as researcher Dr. Alpert points out, even if you're under this 31 calorie per pound limit I outlined earlier, it doesn't mean that you won't lose muscle mass. It simply represents a threshold value past which the rate of muscle loss starts to become exponentially large. So if you're truly seeking to maintain as much muscle mass as possible or even build muscle while losing fat, then again, a less aggressive deficit would be best. But all in all, if you get motivated by seeing results fast and can adhere to a tough protocol, then by all means go for it. Otherwise, taking a slow and steady approach and making positive, long lasting changes to your lifestyle is what I'd personally recommend, as that's more often than not what's going to deliver you the best results in the long term.
I hope you all enjoyed the video, but just remember guys, that fat loss is often a long journey and the last thing you want to do is just rush into it aimlessly and sacrifice all your hard earned muscle as a result. Exactly why within my Built With Science programs, I'll show you exactly step by step how to train, how much to eat and what to eat such that you can lose fat as fast as your specific body is capable of without sacrificing your muscle in the process. To join today, simply head on over to BuiltWoodScience.com and take the Starting Point Analysis quiz which will determine what program is best for you. Anyways, I hope you enjoyed this one. Please don't forget to support me by giving the video a like leaving a comment down below as to what you'd like to see me cover next, subscribing to the channel and turning on notifications from my channel as well as this all really does help me out. Thank you so much everyone for your continued support. I really do appreciate it and I'll see you next time.
